TOTAL MAXIMUM DAILY LOAD (TMDL) for E. coli in the Lower Clinch River Watershed (HUC 06010207) Anderson, Campbell, Grainger, Knox, Loudon, Morgan, Roane, and Union Counties, Tennessee Final Prepared by: Tennessee Department of Environment and Conservation Division of Water Resources William R. Snodgrass Tennessee Tower 312 Rosa L. Parks Avenue, 11 th Floor Nashville, TN 37243 Submitted July 31, 2017 Approved by EPA Region 4 – September 21, 2017
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TOTAL MAXIMUM DAILY LOAD (TMDL) · E-8 E. coli Load Duration Curve for Bullrun Creek – RM 5.2 E-12 E-9 E. coli Load Duration Curve for Bullrun Creek – RM 16.2 E-13 E-10 E. coli
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A. Land Use Distribution in the Lower Clinch River Watershed A-1 B. Water Quality Monitoring Data for the Lower Clinch River Watershed B-1 C. Load Duration Curve Development and Determination
of Required Daily Loading C-1 D. Hydrodynamic Modeling Methodology D-1 E. Source Area Implementation Strategy E-1 F. Trend Analysis for Waterbodies Impaired by E. coli in the Lower Clinch
River Watershed F-1 G. Public Notice Announcement G-1 H. Public Comments Received H-1 I. Response to Public Comments I-1
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LIST OF FIGURES
Figure Page
1. Location of the Lower Clinch River Watershed 4
2. Level IV Ecoregions in the Lower Clinch River Watershed 5
3. Land Use Characteristics of the Lower Clinch River Watershed 6
4. Waterbodies Impaired by E. coli (as documented on the Final 2014 and Draft 2016 303(d) Lists) 12
5. Water Quality Monitoring Stations in the Lower Clinch River Watershed 18
6. Facilities with NPDES Permits to Discharge Sanitary Wastewater to Impaired Subwatersheds and Drainage Areas of the Lower Clinch River Watershed 21
7. Land Use Area of Lower Clinch River E. coli-Impaired Subwatersheds (less than 10 sq. mi.) 25
8. Land Use Percent of Lower Clinch River E. coli-Impaired Subwatersheds (less than 10 sq. mi.) 25
9. Land Use Area of Lower Clinch River E. coli-Impaired Subwatersheds (greater than 10 sq. mi. & less than 70 sq. mi.) 26
10. Land Use Percent of Lower Clinch River E. coli-Impaired Subwatersheds (greater than 10 sq. mi. & less than 70 sq. mi.) 26
11. Land Use Area of Lower Clinch River E. coli-Impaired Subwatersheds (greater than 70 sq. mi.) 27
12. Land Use Percent of Lower Clinch River E. coli-Impaired Subwatersheds (greater than 70 sq. mi.) 27
13. Five-Zone Flow Duration Curve for Beaver Creek at RM 3.5 35
14. TDA Best Management Practices located in the Lower Clinch River Watershed 40
15. Example Graph of TMDL implementation effectiveness (LDC regression analysis) 49
16. Example Graph of TMDL implementation effectiveness (LDC analysis) 49
17. Example Graph of TMDL implementation effectiveness (box and whisker plot) 50
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LIST OF FIGURES (cont’d)
Figure Page
C-1 Flow Duration Curve for Coal Creek at RM 1.2 C-7
C-2 E. coli Load Duration Curve for Coal Creek at RM 1.2 C-7
D-1 Hydrologic Calibration: Bullrun Creek near Halls Crossroads, TN,
USGS 03535000 (WYs 2008-2012) D-4
D-2 5-Year Hydrologic Comparison: Bullrun Creek, USGS 03535000 D-4
E-1 Flow Duration Curve for Scarboro Creek at RM 0.1 E-3
E-2 E. coli Load Duration Curve for Scarboro Creek at RM 0.1 E-3
E-3 Flow Duration Curve for Hinds Creek at RM 0.7 E-6
E-4 E. coli Load Duration Curve for Hinds Creek at RM 0.7 E-6
E-5 E. coli Load Duration Curve for Beaver Creek – RM 3.5 E-11
E-6 E. coli Load Duration Curve for Beaver Creek – RM 24.7 E-11
E-7 E. coli Load Duration Curve for Beaver Creek – RM 40.1 E-12
E-8 E. coli Load Duration Curve for Bullrun Creek – RM 5.2 E-12
E-9 E. coli Load Duration Curve for Bullrun Creek – RM 16.2 E-13
E-10 E. coli Load Duration Curve for Bullrun Creek – RM 31.1 E-13
E-11 E. coli Load Duration Curve for Byrams Creek – RM 0.4 E-14
E-12 E. coli Load Duration Curve for Coal Creek – RM 1.2 E-14
E-13 E. coli Load Duration Curve for Coal Creek – RM 10.6 E-15
E-14 E. coli Load Duration Curve for E. Fork Poplar Creek – RM 6.9 E-15
E-15 E. coli Load Duration Curve for Ernie’s Creek – RM 0.1 E-16
E-16 E. coli Load Duration Curve for Hinds Creek – RM 0.7 E-16
E-17 E. coli Load Duration Curve for Hinds Creek – RM 6.8 E-17
E-18 E. coli Load Duration Curve for Hinds Creek – RM 14.1 E-17
E-19 E. coli Load Duration Curve for Scarboro Creek – RM 0.1 E-18
E-20 E. coli Load Duration Curve for Willow Fork – RM 0.5 E-18
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LIST OF FIGURES (cont’d)
Figure Page
F-1 Time Series Plot for Beaver Creek – RM 3.5 F-5
F-2 Box and Whisker Plot for Beaver Creek – RM 3.5 F-5
F-3 Time Series Plot for Beaver Creek – RM 24.7 F-6
F-4 Box and Whisker Plot for Beaver Creek – RM 24.7 F-6
F-5 Time Series Plot for Beaver Creek – RM 40.1 F-7
F-6 Box and Whisker Plot for Beaver Creek – RM 40.1 F-7
F-7 Box and Whisker Plot for Beaver Creek – 2013 Monitoring F-8
F-8 Time Series Plot for Buffalo Creek – RM 0.3 & 0.7 F-9
F-9 Box and Whisker Plot for Buffalo Creek – RM 0.3 & 0.7 F-9
F-10 Time Series Plot for Bullrun Creek – 3 sites F-10
F-11 Box and Whisker Plot for Bullrun Creek – RM 5.2 F-10
F-12 Box and Whisker Plot for Bullrun Creek – RM 16.2 F-11
F-13 Box and Whisker Plot for Bullrun Creek – 2013 Monitoring F-11
F-14 Time Series Plot for Byrams Creek – RM 0.4 F-12
F-15 Box and Whisker Plot for Byrams Creek – RM 0.4 F-12
F-16 Time Series Plot for Coal Creek – 2 sites F-13
F-17 Box and Whisker Plot for Coal Creek – RM 1.2 F-13
F-18 Box and Whisker Plot for Coal Creek – RM 10.6 F-14
F-19 Box and Whisker Plot for Coal Creek – 2013 Monitoring F-14
F-20 Time Series Plot for E. Fork Poplar Creek – 2 sites F-15
F-21 Box and Whisker Plot for E. Fork Poplar Creek – RM 6.9 F-15
F-22 Time Series Plot for Ernie’s Creek – RM 0.1 F-16
F-23 Box and Whisker Plot for Ernie’s Creek – RM 0.1 F-16
F-24 Time Series Plot for Grassy Creek – RM 0.3 & 0.9 F-17
F-25 Box and Whisker Plot for Grassy Creek – RM 0.3 & 0.9 F-17
F-26 Time Series Plot for Hinds Creek – 3 sites F-18
F-27 Box and Whisker Plot for Hinds Creek – RM 0.7 F-18
F-28 Box and Whisker Plot for Hinds Creek – RM 6.8 F-19
F-29 Box and Whisker Plot for Hinds Creek – RM 14.1 F-19
F-30 Box and Whisker Plot for Hinds Creek – 2013 Monitoring F-20
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LIST OF FIGURES (cont’d)
Figure Page
F-31 Time Series Plot for Hines Creek – RM 0.2 F-21
F-32 Box and Whisker Plot for Hines Creek – RM 0.2 F-21
F-33 Time Series Plot for Knob Creek – RM 0.3 & 0.8 F-22
F-34 Box and Whisker Plot for Knob Creek – RM 0.3 & 0.8 F-22
F-35 Time Series Plot for Meadow Creek – RM 0.2 F-23
F-36 Box and Whisker Plot for Meadow Creek – RM 0.2 F-23
F-37 Time Series Plot for N. Fork Bullrun Creek – RM 0.1 F-24
F-38 Box and Whisker Plot for N. Fork Bullrun Creek – RM 0.1 F-24
F-39 Time Series Plot for Plumb Creek – RM 0.3 F-25
F-40 Box and Whisker Plot for Plumb Creek – RM 0.3 F-25
F-41 Time Series Plot for Scarboro Creek – RM 0.1 F-26
F-42 Box and Whisker Plot for Scarboro Creek – RM 0.1 F-26
F-43 Time Series Plot for Willow Fork – RM 0.5 F-27
F-44 Box and Whisker Plot for Willow Fork – RM 0.4 F-27
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LIST OF TABLES
Table Page
1. MRLC Land Use Distribution – Lower Clinch River Watershed 7
2. Waterbody-Specific Designated Use Classifications 8
3. Extract from Final 2014 and Draft 2016 303(d) Lists for E. coli Impaired Waterbodies – Lower Clinch River Watershed 10
4. Summary of TDEC Water Quality Monitoring Data 15
5. Summary of DOE Water Quality Monitoring Data 17
6. Facilities with NPDES Permits to Discharge Sanitary Wastewater to Impaired Subwatersheds and Drainage Areas of the Lower Clinch River Watershed 20
7. Livestock Distribution in the Lower Clinch River Watershed 24
8. Estimated Population on Septic Systems in the Lower Clinch River Watershed 24
9. Determination of Analysis Areas for TMDL Development 29
10. TMDLs, WLAs & LAs expressed as daily loads for Impaired Waterbodies in the Lower Clinch River Watershed 32
11. Source area types for waterbody drainage area analysis 44
12. Example Urban Area Management Practice/Hydrologic Flow Zone Considerations 45
13. Example Agricultural Management Practice/Hydrologic Flow Zone Considerations 46
A-1 Land Use Distribution of Impaired HUC-12s & Drainage Areas A-2
B-1 TDEC Water Quality Monitoring Data B-2
B-2 DOE Water Quality Monitoring Data B-18
C-1 TMDLs, WLAs, & LAs for Impaired Waterbodies in the Lower Clinch River Watershed (06010207) C-8
D-1 Hydrologic Calibration Summary: Bullrun Creek near Halls Crossroads, TN (USGS 03535000) D-3
E-1 Load Duration Curve Summary for Implementation Strategies (Example: Scarboro Creek Subwatershed, HUC-12 06010207-0403)
(4 Flow Zones) E-4
E-2 Load Duration Curve Summary for Implementation Strategies (Example: Hinds Creek Subwatershed, HUC-12 06010207-0402)
(5 Flow Zones) E-7
E-3 Summary of Critical Conditions for Impaired Waterbodies in the Lower Clinch River Watershed E-10
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LIST OF TABLES (cont’d)
Table Page
E-4 Calculated Load Reduction Based on Daily Loading – Beaver Creek – RM 3.5 E-19
E-5 Calculated Load Reduction Based on Geomean Data – Beaver Creek – RM 3.5 E-19
E-6 Calculated Load Reduction Based on Daily Loading – Beaver Creek – RM 24.7 E-20
E-7 Calculated Load Reduction Based on Geomean Data – Beaver Creek – RM 24.7 E-20
E-8 Calculated Load Reduction Based on Daily Loading – Beaver Creek – RM 40.1 E-21
E-9 Calculated Load Reduction Based on Geomean Loading – Beaver Creek – RM 40.1 E-21
E-10 Calculated Load Reduction Based on Daily Loading – Bullrun Creek – RM 5.2 E-22
E-11 Calculated Load Reduction Based on Geomean Data – Bullrun Creek – RM 5.2 E-22
E-12 Calculated Load Reduction Based on Daily Loading – Bullrun Creek– RM 16.2 E-23
E-13 Calculated Load Reduction Based on Geomean Data – Bullrun Creek – RM 16.2 E-23
E-14 Calculated Load Reduction Based on Daily Loading – Bullrun Creek – RM 31.1 E-24
E-15 Calculated Load Reduction Based on Geomean Data – Bullrun Creek – RM 31.1 E-24
E-16 Calculated Load Reduction Based on Daily Loading – Byrams Creek – RM 0.4 E-25
E-17 Calculated Load Reduction Based on Geomean Data – Byrams Creek – RM 0.4 E-25
E-18 Calculated Load Reduction Based on Daily Loading – Coal Creek – RM 1.2 E-26
E-19 Calculated Load Reduction Based on Geomean Data – Coal Creek – RM 1.2 E-26
E-20 Calculated Load Reduction Based on Daily Loading – Coal Creek – RM 10.6 E-27
E-21 Calculated Load Reduction Based on Geomean Data – Coal Creek – RM 10.6 E-27
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LIST OF TABLES (cont’d)
Table Page
E-22 Calculated Load Reduction Based on Daily Loading – E. Fork Poplar Creek – RM 6.9 E-28
E-23 Calculated Load Reduction Based on Geomean Data – E. Fork Poplar Creek – RM 6.9 E-28
E-24 Calculated Load Reduction Based on Daily Loading – Ernie’s Creek – RM 0.1 E-29
E-25 Calculated Load Reduction Based on Daily Loading – Hinds Creek – RM 0.7 E-29
E-26 Calculated Load Reduction Based on Geomean Data – Hinds Creek – RM 0.7 E-30
E-27 Calculated Load Reduction Based on Daily Loading – Hinds Creek – RM 6.8 E-30
E-28 Calculated Load Reduction Based on Daily Loading – Hinds Creek – RM 14.1 E-31
E-29 Calculated Load Reduction Based on Geomean Data – Hinds Creek – RM 14.1 E-31
E-30 Calculated Load Reduction Based on Daily Loading – Scarboro Creek – RM 0.1 E-32
E-31 Calculated Load Reduction Based on Daily Loading – Willow Fork – RM 0.5 E-33
E-32 Calculated Load Reduction Based on Geomean Data – Willow Fork – RM 0.35 E-33
E-33 Summary of TMDLs, WLAs, & LAs by Flow Regime for Impaired Waterbodies in the Lower Clinch River Watershed (06010207) E-34
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LIST OF ABBREVIATIONS
ADB Assessment Database
AFO Animal Feeding Operation
BMP Best Management Practices
BST Bacteria Source Tracking
CAFO Concentrated Animal Feeding Operation
CFR Code of Federal Regulations
CFS Cubic Feet per Second
CFU Colony Forming Units CRC
CSO Combined Sewer Overflow
d/s Downstream
DA Drainage Area
DEM Digital Elevation Model
DOE Department of Energy
DS Direct Sources
DWR Division of Water Resources
E. coli Escherichia coli
EPA Environmental Protection Agency
GIS Geographic Information System
HSPF Hydrological Simulation Program - Fortran
HUC Hydrologic Unit Code
LA Load Allocation
LDC Load Duration Curve
MGD Million Gallons per Day
MOS Margin of Safety
MRLC Multi-Resolution Land Characteristic
MS4 Municipal Separate Storm Sewer System
MST Microbial Source Tracking
NHD National Hydrography Dataset
NMP Nutrient Management Plan
NPS Nonpoint Source
NPDES National Pollutant Discharge Elimination System
NRCS Natural Resources Conservation Service
ONRW Outstanding National Resource Water
PCR Polymerase Chain Reaction
PDFE Percent of Days Flow Exceeded
PFGE Pulsed Field Gel Electrophoresis
PLRG Percent Load Reduction Goal
qm Mean daily facility (WWTP) flow (cfs)
qd Facility design flow (cfs)
Q Mean daily in-stream flow (cfs)
RM River Mile
SOP State Operating Permit
SSO Sanitary Sewer Overflow
STP Sewage Treatment Plant
SW Storm Water
SWMP Storm Water Management Plan
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TDA Tennessee Department of Agriculture
TDEC Tennessee Department of Environment & Conservation
TDOT Tennessee Department of Transportation
TMDL Total Maximum Daily Load
TVA Tennessee Valley Authority
TWRA Tennessee Wildlife Resources Agency
u/s Upstream
UCF Unit Conversion Factor
USACE United States Army Corp of Engineers
USDA United States Department of Agriculture
USGS United States Geological Survey
UT Unnamed Tributary
UTK University of Tennessee, Knoxville
WCS Watershed Characterization System
WLA Waste Load Allocation
WQ Water Quality
WWTP Wastewater Treatment Plant
WY Water Year
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SUMMARY SHEET
Total Maximum Daily Load for E. coli in
Lower Clinch River Watershed (HUC 06010207)
Impaired Waterbody Information (Based on Draft 2016 List of Impaired Waters)
State: Tennessee Counties: Anderson, Campbell, Grainger, Knox, Loudon, Morgan, Roane, and Union Watersheds: Lower Clinch River (HUC 06010207) Constituents of Concern: E. coli Waterbodies Addressed in This Document:
Waterbody ID Waterbody Miles Impaired
TN06010207006T_0900 Scarboro Creek 1.99
TN06010207006T_1100 Ernies Creek 4.1
TN06010207011_0200 a Willow Fork 5.9
TN06010207011_0500 a Hines Branch 3.2
TN06010207011_0600 a Knob Fork 8.1
TN06010207011_0700 a Grassy Creek 8.2
TN06010207011_0800 a Meadow Creek 4.96
TN06010207011_0900 Plumb Creek 5.3
TN06010207011_1000 a
Beaver Creek (Melton Hill Reservoir to Hallsdale-Powell STP discharge)
22.5
TN06010207011_2000 a
Beaver Creek (Hallsdale-Powell STP discharge to Willow Fork)
13.7
TN06010207011_3000 a Beaver Creek (Willow Fork to origin) 7.5
TN06010207014_0400 a North Fork Bullrun Creek 19.0
TN06010207014_1000 a Bullrun Creek (Melton Hill Reservoir to Hwy 441) 11.8
TN06010207014_2000 b Bullrun Creek (Hwy 441 to N Fork Bullrun) 15.6
TN06010207014_3000 a Bullrun Creek (N Fork Bullrun to origin) 11.4
TN06010207016_0100 b Buffalo Creek 19.9
TN06010207016_0200 Byrams Creek 22.4
TN06010207016_1000 Hinds Creek (Melton Hill Reservoir to ut near I-75)
6.7
TN06010207016_2000 b Hinds Creek (ut near I-75 to Hinds Creek Rd) 7.1
TN06010207016_3000 a Hinds Creek (Hinds Creek Rd to origin) 8.9
TN06010207026_1000 a
East Fork Poplar Creek (Clinch River embayment to road d/s or Oak Ridge STP)
9.7
TN06010207026_2000 a
East Fork Poplar Creek (road d/s of Oak Ridge STP to origin)
11.3
TN06010207029_1000 a
Coal Creek (Clinch River to Beech Grove Creek)
10.9
TN06010207029_2000 a Coal Creek (Beech Grove Creek to origin) 15.0
a Waterbodies covered by TMDLs approved by EPA in 2005. The TMDLs included in this
document supersede the TMDLs approved by EPA in 2005. b Waterbodies listed on the Draft 2016 303(d) List, but not on the Final 2014 303(d) List.
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Designated Uses:
The designated use classifications for all waterbodies in the Lower Clinch River Watershed include fish and aquatic life, irrigation, livestock watering & wildlife, and recreation. Additional designated use classifications for specific waterbodies are listed in the following table:
Waterbody ID Waterbody Name Portion Designated Use
TN06010207011_1000 Beaver Creek
RM 0.0 to RM 8.4
Domestic Water Supply Industrial Water Supply
RM 8.4 to RM 10.4
Industrial Water Supply
RM 10.4 to RM 17.5
Domestic Water Supply Industrial Water Supply
RM 17.5 to RM 17.9
Industrial Water Supply
RM 17.9 to RM 21.6
Domestic Water Supply Industrial Water Supply
TN06010207011_2000 Beaver Creek RM 23.6 to RM 29.4
Domestic Water Supply Industrial Water Supply
TN06010207011_2000 Beaver Creek
RM 31.4 to origin
Domestic Water Supply Industrial Water Supply TN06010207011_3000
TN06010207014_1000
Bullrun Creek RM 1.0 to
origin Domestic Water Supply TN06010207014_2000
TN06010207014_3000
Water Quality Targets:
Derived from State of Tennessee Water Quality Standards, Chapter 0400-40-03, General Water Quality Criteria, 2015 Version (TDEC, 2015) for recreation use classification (most stringent):
The concentration of the E. coli group shall not exceed 126 colony forming units per 100 mL, as a geometric mean based on a minimum of 5 samples collected from a given sampling site over a period of not more than 30 consecutive days with individual samples being collected at intervals of not less than 12 hours. For the purposes of determining the geometric mean, individual samples having an E. coli concentration of less than 1 per 100 mL shall be considered as having a concentration of 1 per 100 mL.
Additionally, the concentration of the E. coli group in any individual sample taken from a lake, reservoir, State Scenic River, Exceptional Tennessee Water or ONRW (0400-40-03-.06) shall not exceed 487 colony forming units per 100 mL. The concentration of the E. coli group in any individual sample taken from any other waterbody shall not exceed 941 colony forming units per 100 mL.
For further information on Tennessee’s general water quality standards, see:
None of the impaired waterbodies in the Lower Clinch River Watershed are classified as lakes or reservoirs, or as State Scenic Rivers or Exceptional Tennessee Waters.
Waterbodies identified on the Final 2014 303(d) list as impaired due to E. coli. Three additional waterbodies identified on the Draft 2016 303(d) list as impaired due to E. coli are also included. TMDLs were developed for impaired waterbodies on a HUC-12 subwatershed or waterbody drainage area basis.
Under Tennessee’s watershed management approach, each HUC-8 watershed is examined (or re-examined) on a rotating basis. TMDLs were developed for portions of the Lower Clinch River Watershed in 2005. Since that time, (1) Additional monitoring data have been collected; (2) Eight additional waterbodies have been assessed as impaired due to E. coli; and (3) Tennessee’s method of expressing TMDLs has changed to a Q- based (flow-based) load. For all of these reasons, existing TMDLs have been revisited (and re-developed) and TMDLs developed for newly assessed impairments for the Lower Clinch River (HUC 06010207) Watershed. The E. coli TMDLs developed in this document supersede the pathogen TMDLs approved by the U.S. Environmental Protection Agency (EPA) on November 25, 2005 for selected waterbodies in the Lower Clinch River Watershed.
Analysis/Methodology:
The TMDLs for the impaired waterbodies in the Lower Clinch River Watershed were developed using a load duration curve methodology to assure compliance with the E. coli 126 CFU/100 mL geometric mean and the 941 CFU/100 mL maximum water quality criteria. A duration curve is a cumulative frequency graph that represents the percentage of time during which the value of a given parameter is equaled or exceeded. Load duration curves are developed from flow duration curves and can illustrate existing water quality conditions (as represented by loads calculated from monitoring data), how these conditions compare to desired targets, and the region of the waterbody flow zone represented by these existing loads. Load duration curves were also used to determine percent load reduction goals (PLRG) to meet the target maximum loading for E. coli.
Critical Conditions:
Water quality data collected over a period of 5 to 10 years for load duration curve analysis were used to assess the water quality standards representing a range of hydrologic and meteorological conditions.
For each impaired waterbody, critical conditions were determined by evaluating the percent load reduction goals and the percent of samples exceeding TMDL target concentrations (percent exceedance), for each hydrologic flow zone, to meet the target (TMDL) loading for E. coli. The percent load reduction goal and/or the percent exceedance of the greatest magnitude corresponds with the critical flow zone(s).
When available, water quality data collected over a period of up to 15 years were evaluated for determination of relative change (trend analysis).
Seasonal Variation:
The 10-year period used for WinHSPF model simulation and for load duration curve analysis included all seasons and a full range of flow and meteorological conditions.
Margin of Safety (MOS):
Explicit MOS = 10% of the E. coli water quality criteria for each impaired subwatershed or drainage area.
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Summary of TMDLs, WLAs, & LAs expressed as daily loads for the Impaired Waterbodies
in the Lower Clinch River Watershed (HUC 06010207)
HUC-12 Subwatershed (06010207__)
Impaired Waterbody Name Impaired Waterbody ID TMDL MOS
Hinds Creek d,e TN06010207016_2000 (8.242 x 105 x Q)
– (9.158 x 105 x qd) (8.242 x 105 x Q)
– (9.158 x 105 x qd)
Hinds Creek d,e TN06010207016_3000 (1.979 x 106 x Q)
– (2.198 x 106 x qd) (1.979 x 106 x Q)
– (2.198 x 106 x qd)
Buffalo Creek d TN06010207016_0100 (2.073 x 106 x Q)
– (2.303 x 106 x qd) (2.073 x 106 x Q)
– (2.303 x 106 x qd)
Byrams Creek d,e TN06010207016_0200 (3.147 x 106 x Q)
– (3.497 x 106 x qd) (3.147 x 106 x Q)
– (3.497 x 106 x qd)
0403 Ernies Creek d,e TN06010207006T_1100 2.3 x 1010 x Q 2.3 x 109 x Q (2.3x1010 x qm) (1.271 x 107 x Q)
– (1.412 x 107 x qd) (1.271 x 107 x Q)
– (1.412 x 107 x qd)
0404 Scarboro Creek d,e TN06010207006T_0900 2.3 x 1010 x Q 2.3 x 109 x Q (2.3x1010 x qm) (2.119 x 107 x Q)
– (2.354 x 107 x qd) (2.119 x 107 x Q)
– (2.354 x 107 x qd)
Notes: Q = Mean Daily In-stream Flow (cfs). qm = Mean Daily WWTP Flow (cfs) qd = Facility (WWTP) Design Flow (cfs) a. WLAs for WWTPs are expressed as E. coli loads (CFU/day). All current and future WWTPs must meet water quality standards as specified in their NPDES permit. b. Applies to any MS4 discharge loading in the subwatershed. Future MS4s will be assigned waste load allocations (WLAs) consistent with load allocations (LAs) assigned to precipitation induced
nonpoint sources. Compliance is achieved by meeting in-stream single-sample E. coli concentrations of ≤ 941 CFU/100 mL (or 487 CFU/100 mL for lakes, reservoirs, State Scenic Rivers, or Exceptional Tennessee Waters).
c. WLAs and LAs expressed as a “per acre” load are calculated based on the drainage area at the pour point of the HUC-12 subwatershed or drainage area (see Table A-1). As regulated MS4 area increases (due to future growth and/or new MS4 designation), unregulated LA area decreases by an equivalent amount. The sum will continue to equal total subwatershed area.
d. Waterbody Drainage Area (DA) is not coincident with HUC-12(s). e. No WWTPs currently discharging into or upstream of the waterbody. (WLA[WWTPs] Expression is future growth term for new WWTPs.) f. No MS4s currently located in the subwatershed drainage area. (Expression is future growth term for expanding or newly designated MS4s.)
E. coli TMDL Lower Clinch River Watershed (HUC 06010207)
9/21/17 – Final Page 1 of 55
PROPOSED E. COLI TOTAL MAXIMUM DAILY LOAD (TMDL)
Lower Clinch River Watershed (HUC 06010207)
1.0 INTRODUCTION
Section 303(d) of the Clean Water Act requires each state to list those waters within its boundaries for which technology based effluent limitations are not stringent enough to protect any water quality standard applicable to such waters. Listed waters are prioritized with respect to designated use classifications and the severity of pollution. In accordance with this prioritization, states are required to develop Total Maximum Daily Loads (TMDLs) for those waterbodies that are not attaining water quality standards. State water quality standards consist of designated uses for individual waterbodies, appropriate numeric and narrative water quality criteria protective of the designated uses, and an antidegradation statement. The TMDL process establishes the maximum allowable loadings of pollutants for a waterbody that will allow the waterbody to maintain water quality standards. The TMDL may then be used to develop controls for reducing pollution from both point and nonpoint sources in order to restore and maintain the quality of water resources (USEPA, 1991).
2.0 SCOPE OF DOCUMENT
This document presents details of TMDL development for waterbodies in the Lower Clinch River Watershed, identified on the Final 2014 303(d) (TDEC, 2016b) list as not supporting designated uses due to E. coli. Three additional waterbodies identified on the Draft 2016 303(d) (TDEC, 2016a) list as not supporting designated uses due to E. coli are also included. TMDL analyses were performed primarily on a 12-digit hydrologic unit area (HUC-12) basis. In some cases, where appropriate, TMDLs were developed for an impaired waterbody drainage area.
Under Tennessee’s watershed management approach, each HUC-8 watershed is examined (or re-examined) on a rotating basis. TMDLs were developed for portions of the Lower Clinch River Watershed in 2005. Since that time, (1) Additional monitoring data have been collected; (2) Eight additional waterbodies have been assessed as impaired due to E. coli; and (3) Tennessee’s method of expressing TMDLs has changed to a Q- based (flow-based) load. For all of these reasons, existing TMDLs have been revisited (and re-developed) and TMDLs developed for newly assessed impairments for the Lower Clinch River (HUC 06010207) Watershed. The E. coli TMDLs developed in this document supersede the pathogen TMDLs approved by the U.S. Environmental Protection Agency (EPA) on November 29, 2005 for selected waterbodies in the Lower Clinch River Watershed.
3.0 WATERSHED DESCRIPTION
The Lower Clinch River Watershed (HUC 06010207) is located in Anderson, Campbell, Grainger, Knox, Loudon, Morgan, Roane, and Union Counties, in eastern Tennessee (Figure 1). The Lower Clinch River watershed has approximately 854.4 miles of streams and 8,026 reservoir acres (based on the EPA/Tennessee Department of Environment and Conservation (TDEC) Assessment Database (ADB)) and has a drainage area of approximately 628 square miles (mi2). Watershed land use distribution is based on the Multi-Resolution Land Characteristic (MRLC) databases derived from Landsat Thematic Mapper digital images from around 2011. Although changes in the land use of the Lower Clinch River Watershed have occurred since 2011 as a result of rapid development, this is the most current land use data available. Land use for the Lower Clinch River Watershed is
E. coli TMDL Lower Clinch River Watershed (HUC 06010207)
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summarized in Table 1 and shown in Figure 3. Predominant land use in the Lower Clinch River Watershed in Tennessee is forest (62.4%) followed by urban (21.9%) and agriculture (15.7%). Details of land use distribution of impaired subwatersheds in the Lower Clinch River Watershed are presented in Appendix A.
The Lower Clinch River Watershed lies within three Level III ecoregions (Ridge and Valley, Southwestern Appalachians, Central Appalachians) and contains five Level IV subecoregions as shown in Figure 2 (USEPA, 1997):
The Southern Limestone/Dolomite Valleys and Low Rolling Hills (67f) form a heterogeneous region composed predominantly of limestone and cherty dolomite. Landforms are mostly low rolling ridges and valleys, and the soils vary in their productivity. Landcover includes intensive agriculture, urban and industrial, or areas of thick forest. White oak forests, bottomland oak forests, and sycamore-ash-elm riparian forests are the common forest types, and grassland barrens intermixed with cedar-pine glades also occur here.
The Southern Dissected Ridges and Knobs (67i) contain more crenulated, broken, or hummocky ridges, compared to smoother, more sharply pointed sandstone ridges. Although shale is common, there is a mixture and interbedding of geologic materials. The ridges on the east side of Tennessee’s Ridge and Valley tend to be associated with the Ordovician-age Sevier shale, Athens shale, and Holston and Lenoir limestones. These can include calcareous shale, limestone, siltstone, sandstone, and conglomerate. In the central and western part of the ecoregion, the shale ridges are associated with the Cambrian-age Rome Formation: shale and siltstone with beds of sandstone. Chestnut oak forests and pine forests are typical for the higher elevations of the ridges, with areas of white oak, mixed mesophytic forest, and tulip poplar on the lower slopes, knobs, and draws.
Cumberland Plateau (68a) tablelands and open low mountains are about 1000 feet higher than the Eastern Highland Rim (71g) to the west, and receive slightly more precipitation with cooler annual temperatures than the surrounding lower-elevation ecoregions. The plateau surface is less dissected with lower relief compared to the Cumberland Mountains (69d) or the Plateau Escarpment (68c). Elevations are generally 1200-2000 feet, with the Crab Orchard Mountains reaching over 3000 feet. Pennsylvanian-age conglomerate, sandstone, siltstone, and shale is covered by well-drained, acidic soils of low fertility. Bituminous coal that has been extensively surface and underground mined underlies the region. Acidification of first and second order streams is common. Stream siltation and mine spoil bedload deposits continue as long-term problems in these headwater systems. Pockets of severe acid mine drainage persist.
Plateau Escarpment (68c) is characterized by steep, forested slopes and high velocity, high gradient streams. Local relief is often 1000 feet or more. The geologic strata include Mississippian-age limestone, sandstone, shale, and siltstone, and Pennsylvanian-age shale, siltstone, sandstone, and conglomerate. Streams have cut down into the limestone, but the gorge talus slopes are composed of colluvium with huge angular, slabby blocks of sandstone. Vegetation community types in the ravines and gorges include mixed oak and chestnut oak on the upper slopes, mesic forests on the middle and lower slopes (beech-tulip poplar, sugar maple-basswood-ash-buckeye), with hemlock along rocky streamsides and river birch along floodplain terraces.
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Cumberland Mountains (69d), in contrast to the sandstone-dominated Cumberland Plateau (68a) to the west and southwest, are more highly dissected, with narrow-crested steep slopes, and younger Pennsylvanian-age shales, sandstones, siltstones, and coal. Narrow, winding valleys separate the mountain ridges, and relief is often 2000 feet. Cross Mountain, west of Lake City, reaches 3534 feet in elevation. Soils are generally well-drained, loamy, and acidic, with low fertility. The natural vegetation is a mixed mesophytic forest, although composition and abundance vary greatly depending on aspect, slope position, and degree of shading from adjacent landmasses. Large tracts of land are owned by lumber and coal companies, and there are many areas of strip mining. Acid mine drainage is primarily limited to first and second order systems. Siltation as surface run-off remains the primary pollutant from past mining, timber harvest and unpaved roads.
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Figure 1. Location of the Lower Clinch River Watershed
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Figure 2. Level IV Ecoregions in the Lower Clinch River Watershed
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Figure 3. Land Use Characteristics of the Lower Clinch River Watershed
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Table 1. MRLC Land Use Distribution – Lower Clinch River Watershed
Land use Entire Watershed
Code Description [acres] [%]
11 Open Water 9,116 2.25
21 Developed Open Spaces 42,265 10.4
22 Low Intensity Residential 30,464 7.51
23 Medium Intensity Residential 12,404 3.06
24 High Intensity Residential 3,536 0.87
31 Bare Rock/Sand/Clay 1,676 0.41
41 Deciduous Forest 176,534 43.5
42 Evergreen Forest 15,930 3.93
43 Mixed Forest 19,909 4.91
52 Shrub/Scrub 2,235 0.55
71 Grassland/Herbaceous 21,878 5.40
81 Pasture/Hay 63,440 15.6
82 Cultivated Crops 299 0.07
90 Woody Wetlands 5,657 1.40
95 Emergent Herbaceous Wetlands 157 0.04
Total 405,500 100%
Note: A spreadsheet was used for this calculation and values are approximate due to rounding.
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4.0 PROBLEM DEFINITION
The State of Tennessee’s Final 2014 303(d) list (TDEC, 2016b), http://www.tn.gov/assets/entities/environment/attachments/wr_wq_303d-2014-final.pdf, was approved by EPA, Region 4, in May 2016. The Draft 2016 303(d) list (TDEC, 2016a), http://www.tn.gov/assets/entities/environment/attachments/wr_wq_303d-2016-draft.pdf, is currently under review. These lists identified a number of waterbodies in the Lower Clinch River Watershed as not fully supporting designated use classifications due, in part, to E. coli (see Table 2 & Figure 4). The designated use classifications for these waterbodies include fish and aquatic life, irrigation, livestock watering & wildlife, and recreation. Additional designated use classifications for specific waterbodies are listed in Table 2.
Table 2. Waterbody-Specific Designated Use Classifications
Waterbody ID Waterbody Name Portion Designated Use
TN06010207011_1000 Beaver Creek
RM 0.0 to RM 8.4
Domestic Water Supply Industrial Water Supply
RM 8.4 to RM 10.4
Industrial Water Supply
RM 10.4 to RM 17.5
Domestic Water Supply Industrial Water Supply
RM 17.5 to RM 17.9
Industrial Water Supply
RM 17.9 to RM 21.6
Domestic Water Supply Industrial Water Supply
TN06010207011_2000 Beaver Creek RM 23.6 to RM 29.4
Domestic Water Supply Industrial Water Supply
TN06010207011_2000 Beaver Creek
RM 31.4 to origin
Domestic Water Supply Industrial Water Supply TN06010207011_3000
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5.0 WATER QUALITY CRITERIA & TMDL TARGET
As previously stated, the designated use classifications for the Lower Clinch River waterbodies include fish & aquatic life, recreation, irrigation, and livestock watering & wildlife. Of the use classifications with numeric criteria for E. coli, the recreation use classification is the most stringent and will be used to establish target levels for TMDL development. The coliform water quality criteria, for protection of the recreation use classification, is established by State of Tennessee Water Quality Standards, Chapter 0400-40-03, General Water Quality Criteria (TDEC, 2015).
For further information concerning Tennessee’s general water quality criteria and Tennessee’s Antidegradation Statement, including the definition of Exceptional Tennessee Water, see:
The geometric mean standard for the E. coli group of 126 colony forming units per 100 ml (CFU/100 ml) and the sample maximum of 941 CFU/100 ml have been selected as the appropriate numerical targets for TMDL development for all impaired waterbodies in the Lower Clinch River Watershed.
None of the impaired waterbodies in the Lower Clinch River Watershed are classified as lakes or reservoirs, or as State Scenic Rivers or Exceptional Tennessee Waters.
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Table 3. Extract from Final 2014 and Draft 2016 303(d) Lists for E. coli Impaired Waterbodies –
Lower Clinch River Watershed
Waterbody ID Impacted Waterbody Miles/Acres
Impaired Cause (Pollutant) Pollutant Source
TN06010207006T_0900 Scarboro Creek 1.99 Escherichia coli Discharges from MS4 Area
TN06010207006T_1100 Ernies Creek 4.1 Escherichia coli Discharges from MS4 Area
TN06010207011_0200 a
Willow Fork 5.9 Escherichia coli Discharges from MS4 Area
TN06010207011_0500 a
Hines Branch 3.2 Escherichia coli Discharges from MS4 Area
TN06010207011_0600 a
Knob Fork 8.1 Escherichia coli Discharges from MS4 Area
TN06010207011_0700 a
Grassy Creek 8.2 Escherichia coli Discharges from MS4 Area
TN06010207011_0800 a
Meadow Creek 4.96 Escherichia coli Discharges from MS4 Area
TN06010207011_0900 Plumb Creek 5.3 Escherichia coli Discharges from MS4 Area
TN06010207011_1000 a
Beaver Creek
(Melton Hill Reservoir to Hallsdale-Powell STP discharge)
22.5 Escherichia coli Pasture Grazing
Collection System Failure
TN06010207011_2000 a
Beaver Creek
(Hallsdale-Powell STP discharge to Willow Fork)
13.7 Escherichia coli Pasture Grazing
Discharges from MS4 Area Collection System Failure
TN06010207011_3000 a
Beaver Creek
(Willow Fork to origin) 7.5 Escherichia coli
Pasture Grazing Discharges from MS4 Area Collection System Failure
TN06010207014_0400 a
North Fork Bullrun Creek 19.0 Escherichia coli Pasture Grazing
TN06010207014_1000 a
Bullrun Creek
(Melton Hill Reservoir to Hwy 441) 11.8 Escherichia coli
Pasture Grazing Discharges from MS4 Area
TN06010207014_2000 b
Bullrun Creek
(Hwy 441 to N Fork Bullrun Ck) 15.6 Escherichia coli
Pasture Grazing Discharges from MS4 Area
TN06010207014_3000 a
Bullrun Creek
(N Fork Bullrun Creek to origin) 11.4 Escherichia coli Pasture Grazing
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Table 3 (con’t). Extract from Final 2014 and Draft 2016 303(d) Lists for E. coli Impaired Waterbodies –
Lower Clinch River Watershed
Waterbody ID Impacted Waterbody Miles/Acres
Impaired Cause (Pollutant) Pollutant Source
TN06010207016_0100 b
Buffalo Creek 19.9 Escherichia coli Pasture Grazing
TN06010207016_0200 Byrams Creek 22.4 Escherichia coli Pasture Grazing
TN06010207016_1000 Hinds Creek
(Melton Hill Reservoir to ut near I-75)
6.7 Escherichia coli Pasture Grazing
TN06010207016_2000 b
Hinds Creek
(ut near I-75 to Hinds Creek Rd.) 7.1 Escherichia coli Pasture Grazing
TN06010207016_3000 a
Hinds Creek
(Hinds Creek Rd. to origin) 8.9 Escherichia coli Pasture Grazing
TN06010207026_1000 a
East Fork Poplar Creek
(Clinch River embayment to road d/s of Oak Ridge STP)
9.7 Escherichia coli Discharges from MS4 Area Collection System Failure
TN06010207026_2000 a
East Fork Poplar Creek
(road d/s of Oak Ridge STP to origin)
11.3 Escherichia coli Discharges from MS4 Area
TN06010207029_1000 a
Coal Creek
(Clinch River to Beech Grove Ck) 10.9 Escherichia coli Municipal Point Source
TN06010207029_2000 a
Coal Creek
(Beech Grove Ck to origin) 15.0 Escherichia coli Septic Tanks
a Waterbodies covered by TMDLs approved by EPA in 2005. The TMDLs included in this document supersede the TMDLs
approved by EPA in 2005. b
Waterbodies listed on the Draft 2016 303(d) List, but not on the Final 2014 303(d) List.
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Figure 4. Waterbodies Impaired by E. coli (as Documented on the Final 2014 and Draft 2016 303(d) Lists)
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6.0 WATER QUALITY ASSESSMENT AND DEVIATION FROM TARGET
The following water quality monitoring stations provided data for waterbodies identified as impaired for E. coli in the Lower Clinch River Watershed:
HUC-12 06010207-0101:
o BULLR031.1UN – Bullrun Creek, at Hwy 144 bridge, immediately u/s of confluence with North Fork Bull Run Creek
o NFBUL000.1UN – North Fork Bullrun Creek, at mouth, just u/s of Hwy 144 bridge
HUC-12 06010207-0102:
o BULLR005.2AN – Bullrun Creek, at Clinton Hwy bridge
o BULLR016.2KN – Bullrun Creek, at Hwy 441/70 bridge
HUC-12 06010207-0201:
o BEAVE040.1KN – Beaver Creek, at Stormer Road
o HINES000.2KN – Hines Creek, at Cunningham Road bridge
o KNOB000.3KN – Knob Fork, at West Beaver Creek Dr
o KNOB000.8KN – Knob Fork, u/s of Irwin Road
o WILLO000.5KN – Willow Fork, at Halls Crossroads; vicinity of Hwy 131 bridge
HUC-12 06010207-0202:
o BEAVE003.5KN – Beaver Creek, at Swafford Rd bridge
o BEAVE024.7KN – Beaver Creek, 100 ft below Clinton Hwy bridge
o GRASS000.3KN – Grassy Creek, at Beaver Creek Rd
o GRASS000.9KN – Grassy Creek, off 62, at private drive on Tim Graham property
o MEADO000.2KN – Meadow Creek, at Crossland, off Byington
o PLUMB000.3KN – Plumb Creek, at Highgate Circle Rd., just d/s of Hardin Valley, behind house #10038
HUC-12 06010207-0302:
o EFPOP006.9RO – East Fork Poplar Creek, at first bridge at Gum Hollow Rd
o EFPOP008.6AN – East Fork Poplar Creek, at Montery Road bridge. u/s of STP
HUC-12 06010207-0401:
o COAL001.2AN – Coal Creek, at Lovely Spring
o COAL010.6AN – Coal Creek, at Briceville Hwy 116 bridge
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HUC-12 06010207-0402:
o BUFFA000.3AN – Buffalo Creek, d/s Intex discharge (Frank L. Diggs Dr)
o BUFFA000.7AN – Buffalo Creek, at Bethel Buffalo Rd.
o BYRAM000.4AN – Byrams Creek, u/s Hwy 170 bridge
o HINDS000.7AN – Hinds Creek, at Brushy Valley Road bridge
o HINDS006.8AN – Hinds Creek, at Mountain Road bridge
o HINDS014.1AN – Hinds Creek, at Hinds Creek Rd
HUC-12 06010207-0403:
o Station 23 – Ernie’s Creek, at mile 0.1, short distance from the Ernie’s Creek/Clinch River embayment at Clinch River mile 51.1
HUC-12 06010207-0404:
o Station 8 – Scarboro Creek, at mile 0.1, near confluence with Melton Hill Lake
The locations of these monitoring stations are shown in Figure 5. The water quality monitoring results for these stations are tabulated in Appendix B. Examination of the data shows exceedances of the 941 CFU/100 mL maximum E. coli standard at all but two of the monitoring stations on the impaired waterbodies. Water quality monitoring results for those stations are summarized in Tables 4 and 5.
Whenever a minimum of 5 samples was collected at a given monitoring station over a period of not more than 30 consecutive days, the geometric mean was calculated. There were sufficient data to conduct geometric mean analyses for all of the impaired waterbodies except Ernie’s Creek and Scarboro Creek.
Several of the water quality monitoring stations (Tables 4 and 5, and Appendix B) have at least one E. coli sample value reported as >2420. For the purpose of calculating summary data statistics, TMDLs, Waste Load Allocations (WLAs), and Load Allocations (LAs), these data values are treated as (equal to) 2420. Therefore, the calculated results are considered to be estimates. In order to obtain an accurate number for future calculations, E. coli sample analyses at these sites should follow established protocol (see Section 9.4.).
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Table 4. Summary of TDEC Water Quality Monitoring Data
2013 5 260 351.8 461 345.4 0 * If multiple geomean sampling periods are available, the maximum calculated geomean value is recorded. a When two date ranges are presented, the first is period of record and the second is the most recent five year period.
Ngd = no geomean data
Table 5. Summary of DOE Water Quality Monitoring Data
23 (Ernie’s Ck) 1999-2008 9 76 >939.0 >2419 Ngd 3 Ngd = no geomean data
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Figure 5. Water Quality Monitoring Stations in the Lower Clinch River Watershed
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7.0 SOURCE ASSESSMENT
An important part of TMDL analysis is the identification of individual sources, or source categories of pollutants in the watershed that affect E. coli loading and the amount of loading contributed by each of these sources.
Under the Clean Water Act, sources are classified as either point or nonpoint sources. Under 40 CFR §122.2, (http://www.gpo.gov/fdsys/pkg/CFR-2011-title40-vol22/pdf/CFR-2011-title40-vol22-sec122-2.pdf), a point source is defined as a discernable, confined, and discrete conveyance from which pollutants are or may be discharged to surface waters. The National Pollutant Discharge Elimination System (NPDES) program (https://www.epa.gov/npdes/) regulates point source discharges. Point sources can be described by three broad categories: 1) NPDES regulated municipal (https://www.epa.gov/npdes/municipal-wastewater) and industrial (https://www.epa.gov/npdes/industrial-wastewater) wastewater treatment facilities (WWTPs); 2) NPDES regulated industrial and municipal stormwater discharges (https://www.epa.gov/npdes/npdes-stormwater-program); and 3) NPDES regulated Concentrated Animal Feeding Operations (CAFOs) (https://www.epa.gov/npdes/animal-feeding-operations-afos). A TMDL must provide Waste Load Allocations (WLAs) for all NPDES regulated point sources. Nonpoint sources are diffuse sources that cannot be identified as entering a waterbody through a discrete conveyance at a single location. For the purposes of this TMDL, all sources of pollutant loading not regulated by NPDES permits are considered nonpoint sources. The TMDL must provide a Load Allocation (LA) for these sources. 7.1 Point Sources 7.1.1 NPDES Regulated Municipal and Industrial Wastewater Treatment Facilities Both treated and untreated sanitary wastewater contain coliform bacteria. There are 9 facilities located in or upstream of impaired subwatersheds or drainage areas in the Lower Clinch River Watershed that have NPDES permits authorizing the discharge of treated sanitary wastewater (Figure 6 and Table 6). Three of the nine facilities are sewage treatment plants (STPs) serving municipalities with design capacities equal to or greater than 1.0 million gallons per day (MGD). The permit limits for discharges from these WWTPs are in accordance with the coliform criteria specified in Tennessee Water Quality Standards for the protection of the recreation use classification.
Non-permitted point sources of (potential) E. coli contamination of surface waters associated with STP collection systems include leaking collection systems and sanitary sewer overflows (SSOs).
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Table 6. Facilities with NPDES Permits to Discharge Sanitary Wastewater
To Impaired Subwatersheds and Drainage Areas
Of the Lower Clinch River Watershed
NPDES Permit No.
Facility Design Flow
Receiving Stream [MGD]
*TN0020630 Norris STP 0.2 Buffalo Creek mile 2.2
*TN0022870 Maynardville STP 0.6 N Fork Bullrun Creek mile 3.1
*TN0024155 Oak Ridge STP 10 E Fork Poplar Creek mile 8.3
*TN0025127 City of Rocky Top STP 0.95 Coal Creek mile 3.3
*TN0057860 Briceville ES 1 0.009 Coal Creek mile 8.6
*TN0059323 Hallsdale-Powell Raccoon
Valley STP 0.3 Bullrun Creek mile 12.6
*TN0060020 West Knox UD – Karns
Beaver Creek STP 4 Beaver Creek mile 10.7
TN0074071 ACWA – Airbase STP 0.1 Slatestone Creek mile 1.5
*TN0078905 Hallsdale-Powell UD STP 9.7 Beaver Creek mile 23.5
*Discharges to impaired waterbody 1 ES = Elementary School
7.1.2 NPDES Regulated Municipal Separate Storm Sewer Systems (MS4s)
Municipal Separate Storm Sewer Systems (MS4s) are considered to be potential point sources of E. coli. Discharges from MS4s occur in response to storm events through road drainage systems, curb and gutter systems, ditches, and storm drains. Phase I of the EPA stormwater program (http://www.epa.gov/npdes/stormwater-discharges-municipal-sources#overview) requires large and medium MS4s to obtain NPDES stormwater permits. Large and medium MS4s are those located in incorporated places or counties serving populations greater than 100,000 people. Portions of the Knoxville Phase I MS4 are located in the Lower Clinch River Watershed.
As of March 2003, regulated small MS4s in Tennessee must also obtain NPDES permits in accordance with the Phase II stormwater program (https://www.epa.gov/npdes/municipal-sources-resources). A small MS4 is designated as regulated if: a) it is located within the boundaries of a defined urbanized area that has a residential population of at least 50,000 people and an overall population density of 1,000 people per square mile; b) it is located outside of an urbanized area but within a jurisdiction with a population of at least 10,000 people, a population density of 1,000 people per square mile, and has the potential to cause an adverse impact on water quality; or c) it is located outside of an urbanized area but contributes substantially to the pollutant loadings of a physically interconnected MS4 regulated by the NPDES stormwater program. Most regulated small MS4s in Tennessee obtain coverage under the NPDES General Permit for Discharges from Small Municipal Separate Storm Sewer Systems http://www.tn.gov/environment/article/permit-water-stormwater-
discharges-permitting (TDEC, 2016c). The city of Oak Ridge and the counties of Anderson, Knox, and Loudon are covered under Phase II of the NPDES Stormwater Program.
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Figure 6. Facilities with NPDES Permits to Discharge Sanitary Wastewater to Impaired Subwatersheds and Drainage
Areas of the Lower Clinch River Watershed
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The Tennessee Department of Transportation (TDOT) has been issued an individual MS4 permit (TNS077585) that authorizes discharges of stormwater runoff from State roads and interstate highway rights-of-way that TDOT owns or maintains, discharges of stormwater runoff from TDOT owned or operated facilities, and certain specified non-stormwater discharges. This permit covers all eligible TDOT discharges statewide, including those located outside of urbanized areas. For information about TDOT’s stormwater management program, see the TDOT website: https://www.tn.gov/tdot/topic/storm-water-management-plan
For information regarding stormwater permitting in Tennessee, see the TDEC website: http://www.tn.gov/environment/article/permit-water-stormwater-permitting-program
Animal feeding operations (AFOs) are agricultural enterprises where animals are kept and raised in confined situations. AFOs congregate animals, feed, manure and urine, dead animals, and production operations on a small land area. Feed is brought to the animals rather than the animals grazing or otherwise seeking feed in pastures, fields, or on rangeland (USEPA, 2002a). Concentrated Animal Feeding Operations (CAFOs) are AFOs that meet certain criteria with respect to animal type, number of animals, and type of manure management system. CAFOs are considered to be potential point sources of E. coli loading and are required to obtain a State Operating Permit (SOP) or an NPDES permit. Most CAFOs in Tennessee qualify as Class II and obtain coverage under SOPC00000, SOPCE0000, or SOPCI0000, General State Operating Permit for Concentrated Animal Feeding Operations (https://www.tn.gov/environment/article/permit-water-concentrated-animal-feeding-operation-cafo-general-state-opera), while larger, Class I CAFOs are required to obtain an individual NPDES permit.
As of March 28, 2017, there are no Class I or II CAFOs in the Lower Clinch River watershed with coverage or pending coverage under individual permits or SOPs, respectively.
7.2 Nonpoint Sources
Nonpoint sources of coliform bacteria are diffuse sources that cannot be identified as entering a waterbody through a discrete conveyance at a single location. These sources generally, but not always, involve accumulation of coliform bacteria on land surfaces and wash off as a result of storm events. Nonpoint sources of E. coli loading are primarily associated with agricultural and urban land uses. The majority of waterbodies identified on the Final 2014 and Draft 2016 303(d) Lists as impaired due to E. coli are attributed to nonpoint agricultural or urban sources.
7.2.1 Wildlife
Wildlife feces contain coliform bacteria which can be deposited onto land surfaces where it can be transported during storm events to nearby streams. The overall deer density for Tennessee was estimated by the Tennessee Wildlife Resources Agency (TWRA) to be 23 animals per square mile. Wildlife are included in the allocation for the LASW term in the TMDL.
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7.2.2 Agricultural Animals
Agricultural activities can be a significant source of coliform bacteria loading to surface waters. The activities of greatest concern are typically those associated with livestock operations:
Agricultural livestock grazing in pastures deposit manure containing coliform bacteria onto land surfaces. This material accumulates during periods of dry weather and is available for washoff and transport to surface waters during storm events. The number of animals in pasture and the time spent grazing are important factors in determining the loading contribution.
Processed agricultural manure from confined feeding operations is often applied to land surfaces and can provide a significant source of coliform bacteria loading. Guidance for issues relating to manure application is available through the University of Tennessee Agricultural Extension Service and the Natural Resources Conservation Service (NRCS).
Agricultural livestock and other unconfined animals often have direct access to waterbodies and can provide a concentrated source of coliform bacteria loading directly to a stream.
Data sources related to livestock operations include the 2012 Census of Agriculture. Livestock data for counties located within the Lower Clinch River Watershed are summarized in Table 7. Note that, due to confidentiality issues, any tabulated item that identifies data reported by a respondent or allows a respondent’s data to be accurately estimated or derived is suppressed and coded with a ‘D’ (USDA, 2014). Agricultural animals are included in the allocation for the LASW term in the TMDL. (See Section C.2.)
7.2.3 Failing Septic Systems
Some of the coliform loading in the Lower Clinch River Watershed can be attributed to failure of septic systems and illicit discharges of raw sewage. Estimates of population utilizing septic systems for counties in the Lower Clinch River Watershed were derived from 2010 county census data and the percent of population on septic systems in 1990 (the last year the data are available), and are summarized in Table 8. In Tennessee, it is estimated that there are approximately 2.47 people per household on septic systems, some of which can be reasonably assumed to be failing. As with livestock in streams, failing septic systems have the potential to provide a concentrated source of coliform bacteria directly to waterbodies. Failing septic tanks are not included in the TMDL and receive an allocation of zero. (See Section C.2.)
7.2.4 Urban Development Nonpoint source loading of coliform bacteria from urban land use areas is attributable to multiple sources. These include: stormwater runoff, illicit discharges of sanitary waste, runoff from improper disposal of waste materials, leaking septic systems, and domestic animals. Impervious surfaces in urban areas allow runoff to be conveyed to streams quickly, without interaction with soils and groundwater. Urban land use area in impaired subwatersheds in the Lower Clinch River Watershed ranges from 6.9% to 85.8%. Land use for the Lower Clinch River drainage areas is summarized in Figures 7-12, and tabulated in Appendix A. Urban development is included in the allocation for the LASW term in the TMDL.
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Table 7. Livestock Distribution in the Lower Clinch River Watershed
County
Livestock Population (2012 Census of Agriculture)
Beef Cow Milk Cow Poultry
Hogs Sheep Goats Horse Layers Broilers
Anderson (D) (D) 1,944 42 138 267 548 447
Campbell (D) (D) 811 (D) 46 125 394 240
Grainger 12,102 338 1,025 148 3 7557 890 1,148
Knox (D) (D) 1,723 112 48 280 956 1,686
Loudon 7,102 2,655 1,153 26 286 153 288 1,165
Morgan 4,205 133 (D) 347,151 84 394 383 601
Roane 5,045 225 1,316 160 94 296 242 744
Unicoi (D) (D) 112 62 (D) 44 74 52
* In keeping with the provisions of Title 7 of the United States Code, no data are published in the 2012 Census of Agriculture that would disclose information about the operations of an individual farm or ranch. Any tabulated item that identifies data reported by a respondent or allows a respondent’s data to be accurately estimated or derived is suppressed and coded with a ‘D’ (USDA, 2014).
Table 8. Estimated Population on Septic Systems in the Lower Clinch River Watershed
County % of Population on
Septic Systems (1990) Total Population (2010
Census) Estimated Population
on Septic (2010)*
Anderson 37.7 75,129 28,324
Campbell 58.7 40,716 23,900
Grainger 88.3 22,657 20,006
Knox 24.7 432,226 106,760
Loudon 59.5 48,556 28,891
Morgan 87.5 21,987 19,239
Roane 59.0 54,181 31,967
Unicoi 62.0 18,313 11,354
* Estimate based on 2010 census and 1990 percent of population on septic.
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0
500
1,000
1,500
2,000
2,500
3,000
3,500
4,000
4,500
5,000
Willow Fk DA Ernies Ck DA Scarboro Ck DA
Are
a (
acre
s)
Subwatershed
Urban
Agriculture
Forest
Open Water
Figure 7. Land Use Area of Lower Clinch River E. coli-Impaired Subwatersheds
(less than 10 sq. mi.)
0%
20%
40%
60%
80%
100%
Willow Fk DA Ernies Ck DA Scarboro Ck DA
Are
a (
perc
en
t)
Subwatershed
Urban
Agriculture
Forest
Open Water
Figure 8. Land Use Percent of Lower Clinch River E. coli-Impaired
Subwatersheds (less than10 sq. mi.)
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0
5,000
10,000
15,000
20,000
25,000
30,000
35,000
40,000
45,000
Hinds Ck (HUC-12 0402) Coal Creek DA E Fork Poplar Ck (HUC-12 0302)
Are
a (
acre
s)
Subwatershed
Urban
Agriculture
Forest
Open Water
Figure 9. Land Use Area of Lower Clinch River E. coli-Impaired Subwatersheds
(greater than 10 sq. mi. and less than 70 sq. mi.)
0%
20%
40%
60%
80%
100%
Hinds Ck (HUC-12 0402) Coal Creek DA E Fork Poplar Ck (HUC-12 0302)
Are
a (
perc
en
t)
Subwatershed
Urban
Agriculture
Forest
Open Water
Figure 10. Land Use Percent of Lower Clinch River E. coli-Impaired
Subwatersheds (greater than 10 sq. mi. and less than 70 sq. mi.)
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0
10,000
20,000
30,000
40,000
50,000
60,000
70,000
Bullrun Ck (HUC-12 0101+0102) Beaver Ck (HUC-12 0201+0202)
Are
a (
acre
s)
Subwatershed
Urban
Agriculture
Forest
Open Water
Figure 11. Land Use Area of Lower Clinch River E. coli-Impaired Subwatersheds
(greater than 70 sq. mi.)
0%
20%
40%
60%
80%
100%
Bullrun Ck (HUC-12 0101+0102) Beaver Ck (HUC-12 0201+0202)
Are
a (
perc
en
t)
Subwatershed
Urban
Agriculture
Forest
Open Water
Figure 12. Land Use Percent of Lower Clinch River E. coli-Impaired
Subwatersheds (greater than 70 sq. mi.)
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8.0 DEVELOPMENT OF TOTAL MAXIMUM DAILY LOADS
The Total Maximum Daily Load (TMDL) process quantifies the amount of a pollutant that can be assimilated in a waterbody, identifies the sources of the pollutant, and recommends regulatory or other actions to be taken to achieve compliance with applicable water quality standards based on the relationship between pollution sources and in-stream water quality conditions. A TMDL can be expressed as the sum of all point source loads (Waste Load Allocations), nonpoint source loads (Load Allocations), and an appropriate margin of safety (MOS) that takes into account any uncertainty concerning the relationship between effluent limitations and water quality:
TMDL = WLAs + LAs + MOS The objective of a TMDL is to allocate loads among all of the known pollutant sources throughout a watershed so that appropriate control measures can be implemented and water quality standards achieved. 40 CFR §130.2 (i) (http://www.gpo.gov/fdsys/pkg/CFR-2011-title40-vol22/pdf/CFR-2011-title40-vol22-sec130-2.pdf) states that TMDLs can be expressed in terms of mass per time, toxicity, or other appropriate measure.
This document describes TMDL, Waste Load Allocation (WLA), Load Allocation (LA), and Margin of Safety (MOS) development for waterbodies identified as impaired due to E. coli on the Final EPA Approved 2014 and Draft 2016 303(d) lists. 8.1 Expression of TMDLs, WLAs, & LAs In this document, the E. coli TMDL is a daily load expressed as a function of mean daily flow (daily loading function). For implementation purposes, corresponding percent load reduction goals (PLRGs) to decrease E. coli loads to TMDL target levels, within each respective flow zone, are also expressed. WLAs & LAs for precipitation-induced loading sources are also expressed as daily loading functions in CFU/day/acre. Allocations for loading that is independent of precipitation (WLAs for WWTPs and LAs for “other direct sources”) are expressed as CFU/day. 8.2 Area Basis for TMDL Analysis The primary area unit of analysis for TMDL development was the HUC-12 subwatershed containing one or more waterbodies assessed as impaired due to E. coli (as documented on the Final 2014 and Draft 2016 303(d) Lists). In some cases, however, TMDLs may be developed for an impaired waterbody drainage area only. Determination of the appropriate area to use for analysis (see Table 9) was based on a careful consideration of a number of relevant factors, including: 1) location of impaired waterbodies in the HUC-12 subwatershed; 2) land use type and distribution; 3) water quality monitoring data; and 4) the assessment status of other waterbodies in the HUC-12 subwatershed.
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Table 9. Determination of Analysis Areas for TMDL Development
Subwatershed (06010207____)
Impaired Waterbody Area
0101/0102
Bullrun Creek (014_1000)
HUC-12 Bullrun Creek (014_2000)
Bullrun Creek (014_3000)
North Fork Bullrun Creek
0201/0202
Beaver Creek (011_1000)
HUC-12
Beaver Creek (011_2000)
Beaver Creek (011_3000)
Grassy Creek
Hines Creek
Knob Fork
Meadow Creek
Plumb Creek
0201 Willow Fork DA
0302 E Fork Poplar Creek (026_1000)
HUC-12 E Fork Poplar Creek (026_2000)
0401 Coal Creek (029_1000)
DA Coal Creek (029_2000)
0402
Hinds Creek (016_1000)
HUC-12
Hinds Creek (016_2000)
Hinds Creek (016_3000)
Buffalo Creek
Byrams Creek
0403 Ernie’s Creek DA
0404 Scarboro Creek DA
Note: HUC-12 = HUC-12 Subwatershed DA = Waterbody Drainage Area
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8.3 TMDL Analysis Methodology TMDLs for the Lower Clinch River Watershed were developed using load duration curves for analysis of impaired HUC-12 subwatersheds or specific waterbody drainage areas. A load duration curve (LDC) is a cumulative frequency graph that illustrates existing water quality conditions (as represented by loads calculated from monitoring data), how these conditions compare to desired targets, and the portion of the waterbody flow zone represented by these existing loads. Load duration curves are considered to be well suited for analysis of periodic monitoring data collected by grab sample. LDCs were developed at monitoring site locations in impaired waterbodies and daily loading functions were expressed for TMDLs, WLAs, LAs, and MOS. In addition, load reductions (PLRGs) for each flow zone were calculated for prioritization of implementation measures according to the methods described in Appendix E. 8.4 Critical Conditions and Seasonal Variation The critical condition for nonpoint source E. coli loading is an extended dry period followed by a rainfall runoff event. During the dry weather period, E. coli bacteria builds up on the land surface, and is washed off by rainfall. The critical condition for point source loading occurs during periods of low streamflow when dilution is minimized. Both conditions are represented in the TMDL analyses.
A ten- to fifteen-year period between January 1, 1998 and December 31, 2014 was used to simulate flow. (The length of the simulation period varied depending on the period of record of the monitoring data for the selected waterbody.) This period contained a range of hydrologic conditions that included both low and high streamflows. Critical conditions are accounted for in the load duration curve analyses by using the entire period of flow and water quality data available for the impaired waterbodies.
In all subwatersheds, water quality data have been collected during most flow ranges. For each subwatershed, the critical flow zone has been identified based on the incremental levels of impairment relative to the target loads. Based on the location of the water quality exceedances on
the load duration curves and the distribution of critical flow zones, no one delivery mode for E. coli appears to be dominant for waterbodies in the Lower Clinch River Watershed (see Section 9.1.2 and 9.1.3).
Seasonal variation was incorporated in the load duration curves by using the entire simulation period and all water quality data collected at the monitoring stations. Some water quality data were collected during all seasons. Most water quality data were collected during periods of mid-range to low flows. 8.5 Margin of Safety There are two methods for incorporating MOS in TMDL analyses: a) implicitly incorporate the MOS using conservative model assumptions; or b) explicitly specify a portion of the TMDL as the MOS and use the remainder for allocations. For development of E. coli TMDLs in the Lower Clinch River Watershed, an explicit MOS, equal to 10% of the E. coli water quality targets (ref.: Section 5.0), was utilized for determination of WLAs and LAs:
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Instantaneous Maximum (lakes, reservoirs, State Scenic Rivers, or Exceptional Tennessee Waters waterbodies): MOS = 49 CFU/100 ml
Instantaneous Maximum (all other waterbodies): MOS = 94 CFU/100 ml
30-Day Geometric Mean: MOS = 13 CFU/100 ml
8.6 Determination of TMDLs E. coli daily loading functions were calculated for impaired segments in the Lower Clinch River Watershed using LDCs to evaluate compliance with the single sample maximum target concentrations according to the procedure in Appendix C. These TMDL loading functions for impaired segments and subwatersheds are shown in Table 10. 8.7 Determination of WLAs & LAs WLAs for MS4s and LAs for precipitation induced sources of E. coli loading were determined according to the procedures in Appendix C. These allocations represent the available loading after application of the explicit MOS. WLAs for existing WWTPs are equal to their existing NPDES permit limits. Since WWTP permit limits require that E. coli concentrations must comply with water quality criteria (TMDL targets) at the point of discharge and recognition that loading from these facilities are generally small in comparison to other loading sources, further reductions were not considered to be warranted. All waterbody IDs have a WLA term for WWTPs. The “qm” term in the WLAWWTP expression will be equal to the sum of the mean daily discharge for all WWTPs discharging to that waterbody ID. When there is no WWTP currently discharging to a waterbody ID (indicated by superscript e), the “qm” term in the WLAWWTP expression will be zero. The “qm” term provides a future growth allowance to the WLAWWTP expression when there is not an active WWTP, and when a WWTP goes online. WLAs for CAFOs and LAs for “other direct sources” (non-precipitation induced) are equal to zero. WLAs, & LAs are summarized in Table 10.
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Table 10. TMDLs, WLAs, & LAs expressed as daily loads for Impaired Waterbodies
in the Lower Clinch River Watershed (HUC 06010207)
HUC-12 Subwatershed (06010207__)
Impaired Waterbody Name Impaired Waterbody ID TMDL MOS
Hinds Creek d,e TN06010207016_2000 (8.242 x 105 x Q)
– (9.158 x 105 x qd) (8.242 x 105 x Q)
– (9.158 x 105 x qd)
Hinds Creek d,e TN06010207016_3000 (1.979 x 106 x Q)
– (2.198 x 106 x qd) (1.979 x 106 x Q)
– (2.198 x 106 x qd)
Buffalo Creek d TN06010207016_0100 (2.073 x 106 x Q)
– (2.303 x 106 x qd) (2.073 x 106 x Q)
– (2.303 x 106 x qd)
Byrams Creek d,e TN06010207016_0200 (3.147 x 106 x Q)
– (3.497 x 106 x qd) (3.147 x 106 x Q)
– (3.497 x 106 x qd)
0403 Ernies Creek d,e TN06010207006T_1100 2.3 x 1010 x Q 2.3 x 109 x Q (2.3x1010 x qm) (1.271 x 107 x Q)
– (1.412 x 107 x qd) (1.271 x 107 x Q)
– (1.412 x 107 x qd)
0404 Scarboro Creek d,e TN06010207006T_0900 2.3 x 1010 x Q 2.3 x 109 x Q (2.3x1010 x qm) (2.119 x 107 x Q)
– (2.354 x 107 x qd) (2.119 x 107 x Q)
– (2.354 x 107 x qd)
Notes: Q = Mean Daily In-stream Flow (cfs). qm = Mean Daily WWTP Flow (cfs) qd = Facility (WWTP) Design Flow (cfs) a. WLAs for WWTPs are expressed as E. coli loads (CFU/day). All current and future WWTPs must meet water quality standards as specified in their NPDES permit. b. Applies to any MS4 discharge loading in the subwatershed. Future MS4s will be assigned waste load allocations (WLAs) consistent with load allocations (LAs) assigned to precipitation induced
nonpoint sources. Compliance is achieved by meeting in-stream single-sample E. coli concentrations of ≤ 941 CFU/100 mL (or 487 CFU/100 mL for lakes, reservoirs, State Scenic Rivers, or Exceptional Tennessee Waters).
c. WLAs and LAs expressed as a “per acre” load are calculated based on the drainage area at the pour point of the HUC-12 subwatershed or drainage area (see Table A-1). As regulated MS4 area increases (due to future growth and/or new MS4 designation), unregulated LA area decreases by an equivalent amount. The sum will continue to equal total subwatershed area.
d. Waterbody Drainage Area (DA) is not coincident with HUC-12(s). e. No WWTPs currently discharging into or upstream of the waterbody. (WLA[WWTPs] Expression is future growth term for new WWTPs.) f. No MS4s currently located in the subwatershed drainage area. (Expression is future growth term for expanding or newly designated MS4s.)
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9.0 IMPLEMENTATION PLAN
The TMDLs, WLAs, and LAs developed in Section 8 are intended to be the first phase of a long-term effort to restore the water quality of impaired waterbodies in the Lower Clinch River Watershed through reduction of excessive E. coli loading. Adaptive management methods, within the context of the State’s rotating watershed management approach, will be used to modify TMDLs, WLAs, and LAs as required to meet water quality goals.
TMDL implementation activities will be accomplished within the framework of Tennessee’s Watershed Approach (ref: http://www.tn.gov/environment/article/wr-ws-watershed-management-approach). The Watershed Approach is based on a five-year cycle and encompasses planning, monitoring, assessment, TMDLs, WLAs/LAs, and permit issuance. It relies on participation at the federal, state, local and non-governmental levels to be successful. 9.1 Application of Load Duration Curves for Implementation Planning The Load Duration Curve (LDC) methodology (Appendix C) is a form of water quality analysis and presentation of data that aids in guiding implementation by targeting management strategies for appropriate flow conditions. One of the strengths of this method is that it can be used to interpret possible delivery mechanisms of E. coli by differentiating between point and nonpoint source problems. The load duration curve analysis can be utilized for implementation planning. See Cleland (2003) for further information on duration curves and TMDL development. 9.1.1 Flow Zone Analysis for Implementation Planning A major advantage of the duration curve framework in TMDL development is the ability to provide meaningful connections between allocations and implementation efforts (USEPA, 2006). Because the flow duration interval serves as a general indicator of hydrologic condition (i.e., wet versus dry and to what degree), allocations and reduction goals can be linked to source areas, delivery mechanisms, and the appropriate set of management practices. The use of duration curve zones (e.g., high flow, moist, mid-range, dry, and low flow) allows the development of allocation tables (USEPA, 2006) (Appendix E), which can be used to guide potential implementation actions to most effectively address water quality concerns.
For the purposes of implementation strategy development, available E. coli data are grouped according to flow zones, with the number of flow zones determined by the HUC-12 subwatershed or drainage area size, the total contributing area (for non-headwater HUC-12s), and/or the baseflow characteristics of the waterbody. In general, for drainage areas greater than 40 square miles, the duration curves will be divided into five zones (Figure 13): high flows (exceeded 0-10% of the time), moist conditions (10-40%), median or mid-range flows (40-60%), dry conditions (60-90%), and low flows (90-100%). For smaller drainage areas, flows occurring in the low flow zone (baseflow conditions) are often extremely low and difficult to measure accurately. In many small drainage areas, extreme dry conditions are characterized by zero flow for a significant percentage of time. For this reason, the low flow zone is best characterized as a broader range of conditions (or percent time) with subsequently fewer flow zones. Therefore, for most HUC-12 subwatershed drainage areas less than 40 square miles, the duration curves will be divided into four zones: high flows (exceeded 0-10% of the time), moist conditions (10-40%), median or mid-range flows (40-70%), and low flows (70-100%). Some small (<40 mi2) waterbody drainage areas have sustained baseflow (no zero flows) throughout their period of record. For these waterbodies, the duration curves will be divided into five zones. Given adequate data, results (allocations and percent load reduction goals) will be calculated for all
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flow zones; however, less emphasis is placed on the upper 10% flow range for E. coli TMDLs and implementation plans. The highest 10 percent flows, representing flood conditions, are considered non-recreational conditions: unsafe for wading and swimming. Humans are not expected to enter the water due to the inherent hazard from high depths and velocities during these flow conditions. As a rule of thumb, the United States Geological Survey (USGS) National Field Manual for the Collection of Water Quality Data (Lane, 1997) advises its personnel not to attempt to wade a stream for which values of depth (ft) multiplied by velocity (ft/s) equal or exceed 10 ft2/s to collect a water sample. Few observations are typically available to estimate loads under these adverse conditions due to the difficulty and danger of sample collection. Therefore, in general, the 0-10% flow range is beyond the scope of E. coli TMDLs and subsequent implementation strategies.
Figure 13 Five-Zone Flow Duration Curve for Beaver Creek at RM 3.5
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9.1.2 Existing Loads and Percent Load Reductions Each impaired waterbody has a characteristic set of pollutant sources and existing loading conditions that vary according to flow conditions. In addition, maximum allowable loading (assimilative capacity) of a waterbody varies with flow. Therefore, existing loading, allowable loading, and percent load reduction expressed at a single location on the LDC (for a single flow condition) do not appropriately represent the TMDL in order to address all sources under all flow conditions (i.e., at all times) to satisfy implementation objectives. The LDC approach provides a methodology for determination of assimilative capacity and existing loading conditions of a waterbody for each flow zone. Subsequently, each flow zone, and the sources contributing to impairment under the corresponding flow conditions, can be evaluated independently. Lastly, the critical flow zone (with the highest percent load reduction goal and/or the highest percent of samples exceeding the TMDL target) can be identified for prioritization of implementation actions.
Existing loading is calculated for each individual water quality sample as the product of the sample flow (cfs) times the single sample E. coli concentration (times a conversion factor). A percent load reduction is calculated for each water quality sample exceeding the single sample maximum water quality criterion as that required to reduce the existing loading to the product of the sample flow (cfs) times the single sample maximum water quality standard (times a conversion factor). Samples with negative percent load reductions (non-exceedance: concentration below the single sample maximum water quality criterion) are not factored into the calculation of the percent load reduction goals (PLRGs). The PLRG for a given flow zone is calculated as the mean of all the percent load reductions for a given flow zone. (See Appendix E.) 9.1.3 Critical Conditions The critical condition for each impaired waterbody is defined as the flow zone with the largest PLRG and/or percent exceedance, excluding the “high flow” zone because these extremely high flows are not representative of recreational flow conditions, as described in Section 9.1.1. If the PLRG and/or percent exceedance in this zone is greater than all the other zones, the zone with the second highest PLRG and/or percent exceedance will be considered the critical flow zone. The critical conditions are such that if water quality standards were met under those conditions, they would likely be met overall. 9.2 Point Sources 9.2.1 NPDES Regulated Municipal and Industrial Wastewater Treatment Facilities All present and future discharges from industrial and municipal wastewater treatment facilities are required to be in compliance with the conditions of their NPDES permits at all times, including elimination of bypasses and overflows. With few exceptions, in Tennessee, permit limits for treated sanitary wastewater require compliance with coliform water quality standards (ref: Section 5.0) prior to discharge. No additional reduction is required. WLAs for WWTPs are derived from mean daily facility flows and permitted E. coli limits and are expressed as daily loads in CFU per day.
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9.2.2 NPDES Regulated Municipal Separate Storm Sewer Systems (MS4s) For discharges from current and future regulated municipal separate storm sewer systems (MS4s), WLAs are and will be implemented through the appropriate MS4 permit. These permits require the development and implementation of a Storm Water Management Plan (SWMP) that will reduce the discharge of pollutants to the "maximum extent practicable" and not cause or contribute to violations of state water quality standards. A monitoring component to assess the effectiveness of BMPs must also be included in the SWMP. Regulated MS4s that maintain compliance with the provisions of their NPDES permits are considered to be consistent with the assumptions and requirements of the WLAs of this TMDL. For guidance on the six minimum control measures for MS4s regulated under Phase I or Phase II and a menu of BMPs representative of the types of practices that can successfully achieve them, a series of fact sheets are available at: http://www.epa.gov/npdes/national-menu-best-management-practices-bmps-stormwater. For further information on Tennessee’s MS4 permitting program (including links to individual MS4 programs and DWR’s Permits Dataviewer) see:
9.2.3 NPDES Regulated Concentrated Animal Feeding Operations (CAFOs) There are currently no CAFOs present in the Lower Clinch River Watershed. Future CAFOs will be addressed through the appropriate CAFO State Operating Permit (SOP) or the facility’s individual permit. Provisions of the SOP include development and implementation of Nutrient Management Plans (NMPs) and requirements for CAFO liquid waste management systems. For further information, see: https://www.tn.gov/environment/article/permit-water-concentrated-animal-feeding-operation-cafo-general-state-opera.
9.3 Nonpoint Sources The Tennessee Department of Environment & Conservation (TDEC) has no direct regulatory authority over most nonpoint source (NPS) discharges. Reductions of E. coli loading from nonpoint sources will be achieved using a phased approach. Voluntary, incentive-based mechanisms will be used to implement NPS management measures in order to assure that measurable reductions in pollutant loadings can be achieved for the targeted impaired waters. Cooperation and active participation by the general public and various industry, business, and environmental groups is critical to successful implementation of TMDLs. There are links to a number of publications and information resources on EPA’s Nonpoint Source Pollution web page (http://www.epa.gov/polluted-runoff-nonpoint-source-pollution) relating to the implementation and evaluation of nonpoint source pollution control measures.
Local citizen-led and implemented management measures have the potential to provide the most efficient and comprehensive avenue for reduction of loading rates from nonpoint sources. The Water Quality Forum is a coalition of diverse partners including municipalities, utilities, non-profit organizations and businesses working together to keep waters in East Tennessee clean. The partners work together to conduct on the ground projects and education/outreach activities geared toward improving water quality in the Knoxville, Tennessee area. Adopt-A-Watershed involves middle and high school students in curriculum-based projects that use their school’s watershed as a
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“living laboratory” and culminates in student-generated products or services that meet true community needs. Water Fest is a day-long festival at Ijams Nature Center for area students that focuses on environmental and water quality education and outdoor activities. Rainy Day Brush-Off promotes water conservation through the use of locally painted artistic rain barrels. River Rescue has organized 600-plus volunteers a year since 1990 to participate in a one-day cleanup of public shorelines along the Tennessee and Clinch Rivers in Knox, Blount and Anderson Counties. The Environmental Stewardship Program (ESP) works with property owners to find sustainable approaches to stormwater drainage problems. Additional information about the Water Quality Forum is available at: http://waterqualityforum.org. Community-led activities have also been described in TDEC’s 5-Alt Report for Beaver Creek.
9.3.1 Urban Nonpoint Sources Management measures to reduce E. coli loading from urban nonpoint sources are similar to those recommended for MS4s (Sect. 9.2.2). Specific categories of urban nonpoint sources include stormwater, illicit discharges, septic systems, pet waste, and wildlife.
Stormwater: Most mitigation measures for stormwater are not designed specifically to reduce bacteria concentrations (ENSR, 2005). Instead, BMPs are typically designed to remove sediment and other pollutants. Bacteria in stormwater runoff are, however, often attached to particulate matter. Therefore, treatment systems that remove sediment may also provide reductions in bacteria concentrations.
Illicit discharges: Removal of illicit discharges to storm sewer systems, particularly of sanitary wastes, is an effective means of reducing E. coli loading to receiving waters (ENSR, 2005). These include intentional illegal connections from commercial or residential buildings, failing septic systems, and improper disposal of sewage from campers and boats.
Septic systems: When properly installed, operated, and maintained, septic systems effectively reduce E. coli concentrations in sewage. To reduce the release of E. coli, practices can be employed to maximize the life of existing systems, identify failed systems, and replace or remove failed systems (USEPA, 2005a). Alternatively, the installation of public sewers may be appropriate.
Pet waste: If the waste is not properly disposed of, these bacteria can wash into storm drains or directly into waterbodies and contribute to E. coli impairment. Encouraging pet owners to properly collect and dispose of pet waste is the primary means for reducing the impact of pet waste (USEPA, 2002b; USEPA, 2001).
Wildlife: Reducing the impact of wildlife on E. coli concentrations in waterbodies generally requires either reducing the concentration of wildlife in an area or reducing their proximity to the waterbody (ENSR, 2005). The primary means for doing this is to eliminate human inducements for congregation. In addition, in some instances population control measures may be appropriate. Three additional urban nonpoint source resource documents provided by EPA are: National Management Measures to Control Nonpoint Source Pollution from Urban Areas (http://nepis.epa.gov/Exe/ZyPURL.cgi?Dockey=P10004FY.txt) helps citizens and municipalities in urban areas protect bodies of water from polluted runoff that can result from everyday activities. The scientifically sound techniques it presents are among the best practices known today. The guidance will also help states to implement their nonpoint source control programs and municipalities to implement their Phase II Storm Water Permit Programs (Publication Number EPA 841-B-05-004, November 2005).
The Use of Best Management Practices (BMPs) in Urban Watersheds is a comprehensive literature
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review on commonly used urban watershed Best Management Practices (BMPs) that heretofore was not consolidated. The purpose of this document is to serve as an information source to individuals and agencies/municipalities/watershed management groups/etc. on the existing state of BMPs in urban stormwater management (Publication Number EPA/600/R-04/184, September 2004).
The National Menu of Stormwater Best Management Practices website (http://www.epa.gov/npdes/national-menu-best-management-practices-bmps-stormwater) is based on the Stormwater Phase II Rule’s six minimum control measures and was first released in October 2000. As recently as September, 2016, EPA has renamed, reorganized, updated, and enhanced the features of the website, including addition of new fact sheets and revisions of existing fact sheets. Fact sheets can be obtained by following the directions on the above website.
9.3.2 Agricultural Nonpoint Sources BMPs have been implemented in the Lower Clinch River Watershed to reduce the amount of coliform bacteria transported to surface waters from agricultural sources. These BMPs (e.g., animal waste management systems, waste utilization, stream stabilization, fencing, heavy use area treatment, livestock exclusion, etc.) may have contributed to reductions in in-stream concentrations of coliform bacteria in one or more Lower Clinch River Watershed E. coli-impaired subwatersheds during the TMDL evaluation period. The Tennessee Department of Agriculture (TDA) keeps a database of BMPs implemented in Tennessee. Those listed in the Lower Clinch River Watershed are shown in Figure 14. The NRCS has also implemented BMPs in the Lower Clinch River Watershed. Identification and quantification of agricultural sources of coliform bacteria (e.g., livestock access to streams, manure application practices, etc.) would be necessary to increase success of future remediation efforts.
Implementation and monitoring of BMPs are essential to document performance in reducing coliform bacteria loading to surface waters from agricultural sources. Demonstration sites for various types of BMPs should be established and maintained, and their performance (in source reduction) evaluated prior to recommendations for utilization for subsequent implementation. E. coli sampling and monitoring during low-flow (baseflow) and storm periods at sites with and without BMPs and/or before and after implementation of BMPs are necessary to document appropriate BMP operation.
For additional information on agricultural BMPs in Tennessee, see: http://www.tn.gov/assets/entities/agriculture/attachments/AgFarBMPsAgricultural.pdf. An additional agricultural nonpoint source resource provided by EPA is National Management Measures to Control Nonpoint Source Pollution from Agriculture (http://www.epa.gov/polluted-runoff-nonpoint-source-pollution/national-management-measures-control-nonpoint-source-0): a technical guidance and reference document for use by State, local, and tribal managers in the implementation of nonpoint source pollution management programs. It contains information on the best available, economically achievable means of reducing pollution of surface and groundwater from agriculture (EPA 841-B-03-004, July 2003). Information about specific BMPs can be obtained at the following website: http://www.nrcs.usda.gov/wps/portal/nrcs/main/national/technical/cp/ncps/
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Figure 14. TDA Best Management Practices located in the Lower Clinch River Watershed
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9.3.3 Other Nonpoint Sources Additional nonpoint source references (not specifically addressing urban and/or agricultural sources) provided by EPA include: National Management Measures to Control Nonpoint Source Pollution from Forestry (http://www.epa.gov/sites/production/files/2015-10/documents/2005_05_09_nps_forestrymgmt_guidance.pdf) helps forest owners protect lakes and streams from polluted runoff that can result from forestry activities. These scientifically sound techniques are the best practices known today. The report will also help states to implement their nonpoint source control programs (EPA 841-B-05-001, May 2005). 9.4 Additional Monitoring Additional monitoring and assessment activities will determine whether implementation of TMDLs, WLAs, & LAs has resulted in achievement of in-stream water quality targets for E. coli. 9.4.1 TMDL Monitoring Future activities recommended for the Lower Clinch River Watershed:
Evaluate the effectiveness of implementation measures (see Sect. 9.6) and include BMP performance analysis and monitoring by permittees and stakeholders.
Provide additional data to clarify status of ambiguous sites (e.g., geometric mean data) for potential listing as an impaired water.
Continue ambient (long-term) monitoring at appropriate sites and key locations.
Comprehensive water quality monitoring activities include sampling during all seasons and a broad range of flow and meteorological conditions. In addition, collection of E. coli data at sufficient frequency to support calculation of the geometric mean, as described in Tennessee’s General Water Quality Criteria (TDEC, 2015), is encouraged only when reductions are expected to be sufficient to support delisting. Finally, for individual monitoring locations, where historical E. coli data are greater than 2419 colonies/100 mL (or future samples are anticipated to be), a 1:10 (or 1:100) dilution should be performed as described in Protocol A of the Quality System Standard Operating Procedure for Chemical and Bacteriological Sampling of Surface Water (TDEC, 2011).
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9.4.2 Source Identification
An important aspect of E. coli load reduction activities is the accurate identification of the actual sources of pollution. In cases where the sources of E. coli impairment are not readily apparent, Microbial Source Tracking (MST) is one approach to determining the sources of fecal pollution and E. coli affecting a waterbody. Those methods that use bacteria as target organisms are also known as Bacterial Source Tracking (BST) methods. This technology is recommended for source identification in E. coli impaired waterbodies.
Bacterial Source Tracking is a collective term used for various biochemical, chemical, and molecular methods that have been developed to distinguish sources of human and non-human fecal pollution in environmental samples (Shah, 2004). In general, these methods rely on genotypic (also known as “genetic fingerprinting”), or phenotypic (relating to the physical characteristics of an organism) distinctions between the bacteria of different sources. Three primary genotypic techniques are available for BST: ribotyping, pulsed field gel electrophoresis (PFGE), and polymerase chain reaction (PCR). Two prominent phenotypic techniques are available for BST: antibiotic resistance analysis (ARA) and carbon utilization profile (CUP).
The USEPA has published a fact sheet that discusses BST methods and presents examples of BST application to TMDL development and implementation (USEPA, 2002b). Various BST projects and descriptions of the application of BST techniques used to guide implementation of effective BMPs to remove or reduce fecal contamination are presented. The fact sheet can be found on the following EPA website: http://www3.epa.gov/npdes/pubs/bacsortk.pdf.
An article about “Advancements in Bacterial Source Tracking” is available at: http://foresternetwork.com/daily/water/stormwater-management/advancements-in-bacterial-source-tracking/. This article provides information about: (1) general types of BST methods, and comparison of the advantages and disadvantages of several of these methodologies, (2) the value of adopting BST techniques in an effort to focus system improvements in a way that reduces costs by placing an emphasis on the right source(s) of bacteria (i.e., human versus non-human), and (3) advances in BST technology, including a list of reading sources to study this topic in greater detail.
A multi-disciplinary group of researchers at the University of Tennessee, Knoxville (UTK) has developed and tested a series of different microbial assay methods based on real-time PCR to detect fecal bacterial concentrations and host sources in water samples (Layton, 2006). The assays have been used in a study of fecal contamination and have proven useful in identification of areas where cattle represent a significant fecal input and in development of BMPs. It is expected that these types of assays could have broad applications in monitoring fecal impacts from Animal Feeding Operations, as well as from wildlife and human sources. Additional information can be found on the following UTK website: http://web.utk.edu/~hydro/JournalPapers/Layton06AEM.pdf. BST technology was utilized in a study conducted in Stock Creek (Little River Watershed) (Layton, 2004). Microbial source tracking using real-time PCR assays to quantify Bacteroides 16S rRNA genes was used to determine the percent of fecal contamination attributable to cattle. E. coli loads attributable to cattle were calculated for each of nine sampling sites in the Stock Creek subwatershed on twelve sampling dates. At the site on High Bluff Branch (tributary to Stock Creek), none of the sample dates had E. coli loads attributable to cattle above the threshold. This suggests that at this site removal of E. coli attributable to cattle would have little impact on the total E. coli loads. The E. coli load attributable to cattle made a large contribution to the total E. coli load at each of the eight remaining sampling sites. At two of the sites (STOCK005.3KN and GHOLL000.6KN), 50–75% of the E. coli attributable to cattle loads alone was above the 126 CFU/100mL threshold. This suggests that removal of the E. coli attributable to cattle at these sites would reduce the total E. coli load to acceptable limits.
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9.5 Source Area Implementation Strategy Implementation strategies are organized according to the dominant landuse type and the sources associated with each (Table 11 and Appendix E). Additional considerations for classification of source area type include waterbody assessment information from TDEC’s ADB and subsequent Pollutant Source designation on the 303(d) List. Each HUC-12 subwatershed and waterbody drainage area is grouped and targeted for implementation based on this source area classification. Three primary categories are identified: predominantly urban, predominantly agricultural, and mixed urban/agricultural. See Appendix A for information regarding landuse distribution of impaired subwatersheds. For the purpose of implementation evaluation, urban is defined as residential, commercial, and industrial landuse areas (landuse classifications: low, medium, and high intensity development) with predominant source categories such as point sources (WWTPs), collection systems/septic systems (including SSOs and CSOs), and urban stormwater runoff associated with MS4s. Agricultural is defined as cropland and pasture, with predominant source categories associated with livestock and manure management activities. A 303(d) List Pollutant Source designation of Undetermined Source warrants classification as mixed source area unless landuse is overwhelmingly dominated by urban or agricultural. A fourth category (infrequent) is associated with forested (including non-agricultural undeveloped and unaltered [by humans]) landuse areas with the predominant source category being wildlife.
All impaired waterbodies and corresponding HUC-12 subwatersheds or drainage areas have been classified according to their respective source area types in Table 11. The implementation for each area will be prioritized according to the guidance provided in Sections 9.5.1 and 9.5.2, below. For all impaired waterbodies, the determination of source area types serves to identify the predominant sources contributing to impairment (i.e., those that should be targeted initially for implementation). However, it is not intended to imply that sources in other landuse areas are not contributors to impairment and/or to grant an exemption from addressing other source area contributions with implementation strategies and corresponding load reduction. For mixed use areas, implementation will follow the guidance established for both urban and agricultural areas, at a minimum.
Appendix E provides source area implementation examples for urban and agricultural subwatersheds, development of percent load reduction goals, and determination of critical flow zones (for implementation prioritization) for E. coli impaired waterbodies. Load duration curve analyses (TMDLs, WLAs, LAs, and MOS) and percent load reduction goals for all flow zones for all E. coli impaired waterbodies in the Lower Clinch River Watershed are summarized in Table E-33.
9.5.1 Urban Source Areas For impaired waterbodies and corresponding HUC-12 subwatersheds or drainage areas classified as predominantly urban, implementation strategies for E. coli load reduction will initially and primarily target source categories similar to those listed in Table 12 (USEPA, 2006). Table 12 presents example urban area management practices and the corresponding potential relative effectiveness under each of the hydrologic flow zones. Each implementation strategy addresses a range of flow conditions and targets point sources, nonpoint sources, or a combination of each. For each waterbody, the existing loads and corresponding PLRG for each flow zone are calculated according to the method described in Section E.1. The resulting determination of the critical flow zone further focuses the types of urban management practices appropriate for development of an effective load reduction strategy for a particular waterbody.
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Table 11. Source area types for waterbody drainage area analyses
HUC-12 / Waterbody Source Area Type*
Urban Agriculture Mixed Forested
Bullrun Creek (014_1000)
Bullrun Creek (014_2000)
Bullrun Creek (014_3000)
North Fork Bullrun Creek
Beaver Creek (011_1000)
Beaver Creek (011_2000)
Beaver Creek (011_3000)
Grassy Creek
Hines Creek
Knob Fork
Meadow Creek
Plumb Creek
Willow Fork
E Fork Poplar Creek (026_1000)
E Fork Poplar Creek (026_2000)
Coal Creek (029_1000)
Coal Creek (029_2000)
Hinds Creek (016_1000)
Hinds Creek (016_2000)
Hinds Creek (016_3000)
Buffalo Creek
Byrams Creek
Ernie’s Creek
Scarboro Creek
* All waterbodies potentially have significant source contributions from other source type/landuse areas.
9.5.2 Agricultural Source Areas For impaired waterbodies and corresponding HUC-12 subwatersheds or drainage areas classified as predominantly agricultural, implementation strategies for E. coli load reduction will initially and primarily target source categories similar to those listed in Table 13 (USDA, 1988). Table 13 presents example agricultural area management practices and the corresponding potential relative effectiveness under each of the hydrologic flow zones. Each implementation strategy addresses a range of flow conditions and targets point sources, nonpoint sources, or a combination of each. For each waterbody, the existing loads and corresponding PLRG for each flow zone are calculated according to the method described in Section E.2. The resulting determination of the critical flow zone further focuses the types of agricultural management practices appropriate for development of an effective load reduction strategy for a particular waterbody.
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Table 12. Example Urban Area Management Practice/Hydrologic Flow Zone
Considerations
Management Practice Duration Curve Zone (Flow Zone)
High Moist Mid-Range Dry Low
Bacteria source reduction
Remove illicit discharges L M H
Address pet & wildlife waste H M M L
Combined sewer overflow management
Combined sewer separation H M L
CSO prevention practices H M L
Sanitary sewer system
Infiltration/Inflow mitigation H M L L
Inspection, maintenance, and repair L M H H
SSO repair/abatement H M L
Illegal cross-connections
Septic system management
Managing private systems L M H M
Replacing failed systems L M H M
Installing public sewers L M H M
Storm water infiltration/retention
Infiltration basin L M H
Infiltration trench L M H
Infiltration/Biofilter swale L M H
Storm Water detention
Created wetland H M L
Low impact development
Disconnecting impervious areas L M H
Bioretention L M H H
Pervious pavement L M H
Green Roof L M H
Buffers H H H
New/existing on-site wastewater treatment
systems
Permitting & installation programs L M H M
Operation & maintenance programs L M H M
Other
Point source controls L M H H
Landfill control L M H
Riparian buffers H H H
Pet waste education & ordinances M H H L
Wildlife management M H H L
Inspection & maintenance of BMPs L M H H L
Note: Potential relative importance of management practice effectiveness under given hydrologic condition (H: High, M: Medium, L: Low)
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Table 13. Example Agricultural Area Management Practice/Hydrologic
Flow Zone Considerations
Flow Condition High Moist Mid-range Dry Low
% Time Flow Exceeded 0-10 10-40 40-60 60-90 90-100
Grazing Management
Prescribed Grazing (528A) H H M L
Pasture & Hayland Mgmt (510) H H M L
Deferred Grazing (352) H H M L
Planned Grazing System (556) H H M L
Proper Grazing Use (528) H H M L
Proper Woodland Grazing (530) H H M L
Livestock Access Limitation
Livestock Exclusion (472) M H H
Fencing (382) M H H
Stream Crossing M H H
Alternate Water Supply
Pipeline (516) M H H
Pond (378) M H H
Trough or Tank (614) M H H
Well (642) M H H
Spring Development (574) M H H
Manure Management
Managing Barnyards H H M L
Manure Transfer (634) H H M L
Land Application of Manure H H M L
Composting Facility (317) H H M L
Vegetative Stabilization
Pasture & Hayland Planting (512) H H M L
Range Seeding (550) H H M L
Channel Vegetation (322) H H M L
Brush (& Weed) Mgmt (314) H H M L
Conservation Cover (327) H H H
Riparian Buffers (391) H H H
Critical Area Planting (342) H H H
Wetland restoration (657) H H H
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Table 13 (cont’d). Example Agricultural Area Management Practice/Hydrologic
Flow Zone Considerations
Flow Condition High Moist Mid-range Dry Low
% Time Flow Exceeded 0-10 10-40 40-60 60-90 90-100
CAFO Management
Waste Management System (312) H H M
Waste Storage Structure (313) H H M
Waste Storage Pond (425) H H M
Waste Treatment Lagoon (359) H H M
Mulching (484) H H M
Waste Utilization (633) H H M
Water & Sediment Control Basin (638) H H M
Filter Strip (393) H H M
Sediment Basin (350) H H M
Grassed Waterway (412) H H M
Diversion (362) H H M
Heavy Use Area Protection (561)
Constructed Wetland (656)
Dikes (356) H H M
Lined Waterway or Outlet (468) H H M
Roof Runoff Mgmt (558) H H M
Floodwater Diversion (400) H H M
Terrace (600) H H M
Potential for source area contribution under given hydrologic condition (H: High; M: Medium; L: Low)
Note: Numbers in parentheses are the U.S. Soil Conservation Service practice number.
9.5.3 Forestry Source Areas There are no impaired waterbodies with corresponding HUC-12 subwatersheds or drainage areas classified as source area type predominantly forested, with the predominant source category being wildlife, within the Lower Clinch River Watershed.
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9.6 Evaluation of TMDL Implementation Effectiveness Evaluation of the effectiveness of TMDL implementation strategies should be conducted on multiple levels, as appropriate:
HUC-12 or waterbody drainage area (i.e., TMDL analysis location)
Subwatersheds or intermediate sampling locations
Specific landuse areas (urban, pasture, etc.)
Specific facilities (WWTP, CAFO, uniquely identified portion of MS4, etc.)
Individual BMPs In order to conduct an implementation effectiveness analysis on measures to reduce E. coli source loading, monitoring results should be evaluated in one of several ways. Sampling results can be compared to water quality standards (e.g., load duration curve analysis) for determination of impairment status, results can be compared on a before and after basis (temporal), or results can be evaluated both upstream and downstream of source reduction measures or source input (spatial). Considerations include period of record, data collection frequency, representativeness of data, and sampling locations.
In general, periods of record greater than 5 years (given adequate sampling frequency) can be evaluated for determination of relative change (trend analysis). For watersheds in second or successive TMDL cycles, data collected from multiple cycles can be compared. If implementation efforts have been initiated to reduce loading, evaluation of routine monitoring data may indicate improving or worsening conditions over time and corresponding effectiveness of implementation efforts.
Water quality data for implementation effectiveness analysis can be presented in multiple ways. The following examples are taken from the Hiwassee River watershed because the monitoring site (Oostanaula Creek at mile 28.4) has a large quantity of monitoring data available and the data demonstrate clear improvement. There were no monitoring sites in the Lower Clinch River watershed with a similar quantity of monitoring data available and showing a definite trend.
Figure 15 shows best fit curve analyses (regressions) of flow (percent time exceeded) versus E. coli loading, for a historical (1999-2004) period versus a recent post-implementation period of sampling data (2005-2013). The LDCs of the single sample maximum and geometric mean water quality standards are also plotted to illustrate the relative degree of impairment for each period. Figure 16 shows a LDC analysis of E. coli loading statistics for Oostanaula Creek for the same two periods. In addition, the 90th percentiles for each flow zone are plotted for comparison. Lastly, Figure 17 shows E. coli concentration data statistics for recent versus historical data. The individual flow zone analyses are presented in a box and whisker plot of recent [2] versus historical [1] data. Note that Figures 15-17 present the same data, each clearly illustrating improving conditions between historical and recent periods.
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Figure 15. Example Graph of TMDL implementation effectiveness (LDC regression analysis)
Figure 16. Example Graph of TMDL implementation effectiveness (LDC analysis)
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Figure 17. Example Graph of TMDL implementation effectiveness (box and whisker plot)
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10.0 PUBLIC PARTICIPATION
In accordance with 40 CFR §130.7, the proposed E. coli TMDLs for the Lower Clinch River Watershed will be placed on Public Notice for a 35-day period and comments solicited. Steps that will be taken in this regard include:
1) Notice of the proposed TMDLs was posted on the Tennessee Department of Environment and Conservation website. The announcement invited public and stakeholder comment and provided a link to a downloadable version of the TMDL document.
2) Notice of the availability of the proposed TMDLs (similar to the website
announcement) was included in one of the NPDES permit Public Notice mailings which is sent to over 190 interested persons or groups who have requested this information.
3) Letters were sent to WWTPs and other facilities located in E. coli-impaired
subwatersheds or drainage areas in the Lower Clinch River Watershed, permitted to discharge treated effluent containing E. coli, advising them of the proposed TMDLs and their availability on the TDEC website and providing a link to a downloadable version of the TMDL document. The letters also stated that a copy of the draft TMDL document would be provided on request. A letter was sent to the following facilities:
ACWA – Airbase STP (TN0074071) Briceville Elementary School (TN0057860) City of Rocky Top STP (TN0025127) Hallsdale-Powell Raccoon Valley STP (TN0059323) Hallsdale-Powell UD STP (TN0078905) Maynardville STP (TN0022870) Norris STP (TN0020630) Oak Ridge STP (TN0024155) West Knox UD – Karns Beaver Creek STP (TN0060020)
4) Letters were sent to those MS4s that are wholly or partially located in E. coli-impaired subwatersheds, advising them of the proposed TMDLs and their availability on the TDEC website and providing a link to a downloadable version of the TMDL document. The letters also stated that a copy of the draft TMDL document would be provided on request. A letter was sent to the following MS4s:
City of Knoxville, Tennessee (TNS068055) Anderson County (TNS075108) Knox County (TNS075582) Loudon County (TNS075591) Oak Ridge Phase II MS4 (TNS088366) Tennessee Dept. of Transportation (TNS077585)
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5) A letter was sent to water quality partners in the Lower Clinch River Watershed advising them of the proposed E. coli TMDLs and their availability on the TDEC website and providing a link to a downloadable version of the TMDL document. The letter also stated that a written copy of the draft TMDL document would be provided upon request. A letter was sent to the following partners:
Water Quality Forum, including: City of Oak Ridge Stormwater Program GeoServices, LLC City of Knoxville Communications Dept. Ijams Nature Center Knox County Stormwater Program McGill Associates S&ME Town of Farragut Stormwater Program UT – Biosystems Engineering & Soil Sciences UT – TN Water Resources Center
Lower Clinch Watershed Council, including: Beaver Creek Task Force Bullrun Creek Restoration Initiative Coal Creek Watershed Foundation Natural Resources Conservation Service Tennessee Citizens for Wilderness Planning Trout Unlimited – Clinch River Chapter Water Quality Forum
Oak Ridge Reservation Local Oversight Committee Tennessee Department of Agriculture Tennessee Wildlife Resources Agency The Nature Conservancy
11.0 FURTHER INFORMATION
Further information concerning Tennessee’s TMDL program can be found on the Internet at the Tennessee Department of Environment and Conservation website:
http://www.tn.gov/environment/article/wr-ws-tennessees-total-maximum-daily-load-tmdl-program Technical questions regarding this TMDL should be directed to the following members of the DWR staff:
Vicki Steed, P.E., Watershed Management Unit e-mail: [email protected] David M. Duhl, Ph.D., Manager, Watershed Management Unit e-mail: [email protected]
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REFERENCES
California Dept. of Transportation (CalTrans). November 2003. Discharge Characterization Study Report. CTSW-RT-03-065.51.42. Available at the following website: http://www.dot.ca.gov/hq/env/stormwater/pdf/CTSW-RT-03-065.pdf.
Center for Watershed Protection, 1999. Watershed Protection Techniques. Vol. 3. No. 1. Center
for Watershed Protection. Ellicott City, MD. April 1999. Cleland, Bruce, 2003. TMDL Development from the “Bottom Up” – Part III: Duration Curves and
Wet-Weather Assessments. America’s Clean Water Foundation. Washington, DC. September 2003. This document can be found at TMDLs.net, a joint effort of America’s Clean Water Foundation, the Association of State and Interstate Water Resources Administrators, and EPA: https://www.researchgate.net/publication/228822472_TMDL_Development_from_the_Bottom_Up-_PART_III_Durations_Curves_and_Wet-Weather_Assessments
ENSR. 2005. Mitigation Measures to Address Pathogen Pollution in Surface Waters: A TMDL
Implementation Guidance Manual for Massachusetts. Prepared by ENSR International for U.S. Environmental Protection Agency, Region 1. July 2005.
Hyer, Kenneth E., and Douglas L. Moyer, 2004. Enhancing Fecal Coliform Total Maximum Daily
Load Models Through Bacterial Source Tracking. Journal of the American Water Resources Association (JAWRA) 40(6):1511-1526. Paper No. 03180.
Lane, S. L., and R. G. Fay, 1997. National Field Manual for the Collection of Water-Quality Data,
Chapter A9. Safety in Field Activities: U.S. Geological Survey Techniques of Water-Resources Investigations, book 9, chap. 9. October 1997. This document is available on the USGS website: http://water.usgs.gov/owq/FieldManual/Chap9/content.html.
Layton, Alice, Gentry, Randy, and McKay, Larry, 2004. Calculation of Stock Creek E. coli loads and
partitioning of E. coli loads into that attributable to bovine using Bruce Cleland’s Flow Duration Curve Models. Personal note.
Layton, Alice, McKay, Larry, Williams, Dan, Garrett, Victoria, Gentry, Randall, and Sayler, Gary,
2006. Development of Bacteriodes 16S rRNA Gene TaqMan-Based Real-Time PCR Assays for Estimation of Total Human, and Bovine Fecal Pollution in Water. Applied and Environmental Microbiology (AEM), June 2006, p. 4214-4224. This document is available on the UTK website: http://web.utk.edu/~hydro/JournalPapers/Layton06AEM.pdf .
Powell, Mike. 2014. Advancements in Bacterial Source Tracking. StormH2O, May 2014, p. 20-27.
This document is available at the following website: http://foresternetwork.com/daily/water/stormwater-management/advancements-in-bacterial-source-tracking/
Shah, Vikas G., Hugh Dunstan, and Phillip M. Geary, 2004. Application of Emerging Bacterial
Source Tracking (BST) Methods to Detect and Distinguish Sources of Fecal Pollution in Waters. School of Environmental and Life Sciences, The University of Newcastle, Callaghan, NSW 2308 Australia.
E. coli TMDL Lower Clinch River Watershed (HUC 06010207)
9/21/17 – Final Page 54 of 55
Stiles, T., and B. Cleland, 2003, Using Duration Curves in TMDL Development & Implementation
Planning. ASIWPCA “States Helping States” Conference Call, July 1, 2003. This document is available on the Indiana Office of Water Quality website: http://www.in.gov/idem/nps/files/monitoring_loads_duration_about_using.pdf.
TDEC. 2011. Quality System Standard Operating Procedure for Chemical and Bacteriological
Sampling of Surface Water. State of Tennessee, Department of Environment and Conservation, Division of Water Resources. August 2011.
TDEC. 2015. State of Tennessee Water Quality Standards, Chapter 0400-40-03 General Water
Quality Criteria. State of Tennessee, Department of Environment and Conservation, Division of Water Resources. April 2015.
TDEC. 2016a. Draft 2016 303(d) List. State of Tennessee, Department of Environment and
Conservation, Division of Water Resources, July 2016. TDEC. 2016b. Final EPA Approved 2014 303(d) List. State of Tennessee, Department of
Environment and Conservation, Division of Water Resources, May 2016. TDEC. 2016c. NPDES General Permit for Discharges from Small Municipal Separate Storm Sewer
Systems. State of Tennessee, Department of Environment and Conservation, Division of Water Resources, August 2010. This document is available on the TDEC website: http://www.tn.gov/environment/article/permit-water-stormwater-discharges-permitting
USDA, 1988. 1-4 Effects of Conservation Practices on Water Quantity and Quality. In Water
Quality Workshop, Integrating Water Quality and Quantity into Conservation Planning. U.S. Department of Agriculture, Soil Conservation Service. Washington, D.C.
USDA, 2014. 2012 Census of Agriculture, Tennessee State and County Data, Volume 1,
Geographic Area Series, Part 42 (AC-12-A-42). USDA website URL: http://www.agcensus.usda.gov/Publications/2012/Full_Report/Volume_1,_Chapter_2_County_Level/Tennessee/tnv1.pdf. May 2014.
USDA, 2016. National Conservation Practice Standards. Available from USDA website URL:
http://www.nrcs.usda.gov/wps/portal/nrcs/main/national/technical/cp/ncps/ USEPA. 1991. Guidance for Water Quality –based Decisions: The TMDL Process. U.S.
Environmental Protection Agency, Office of Water, Washington, DC. EPA-440/4-91-001, April 1991.
USEPA. 1997. Ecoregions of Tennessee. U.S. Environmental Protection Agency, National Health
and Environmental Effects Research Laboratory, Corvallis, Oregon. EPA/600/R-97/022. USEPA, 2001. Managing Pet and Wildlife Waste to Prevent Contamination of Drinking Water. U.S.
Environmental Protection Agency, Office of Water, Washington, DC. EPA-916-F-01-027, July 2001.
E. coli TMDL Lower Clinch River Watershed (HUC 06010207)
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USEPA, 2002b. Wastewater Technology Fact Sheet, Bacterial Source Tracking. U.S. Environmental Protection Agency, Office of Water. Washington, D.C. EPA 832-F-02-010, May 2002. This document is available on the EPA website: http://www3.epa.gov/npdes/pubs/bacsortk.pdf
USEPA. 2003. National Management Measures to Control Nonpoint Source Pollution from
Agriculture. EPA 841-B-03-004. U.S. Environmental Protection Agency. Washington, DC. This document is available on the EPA website: (http://www.epa.gov/polluted-runoff-nonpoint-source-pollution/national-management-measures-control-nonpoint-source-0
USEPA. 2004. The Use of Best Management Practices (BMPs) in Urban Watersheds. U.S. Environmental Protection Agency, Office of Research and Development. Washington, D.C. EPA/600/R-04/184, September 2004.
USEPA. 2005a. National Management Measures to Control Nonpoint Source Pollution from Urban
Areas. U.S. Environmental Protection Agency, Office of Water. Washington, D.C. EPA 841-B-05-004, November 2005. This document is available on the EPA website: (http://nepis.epa.gov/Exe/ZyPURL.cgi?Dockey=P10004FY.txt)
USEPA. 2005b. National Management Measures to Control Nonpoint Source Pollution from
Forestry. U.S. Environmental Protection Agency, Office of Water. Washington, D.C. EPA 841-B-05-001, May 2005. This document is available on the EPA website: (http://www.epa.gov/sites/production/files/2015-10/documents/2005_05_09_nps_forestrymgmt_guidance.pdf
USEPA, 2006. An Approach for Using Load Duration Curves in Developing TMDLs. U.S.
Environmental Protection Agency, Office of Wetlands, Oceans, & Watersheds. Washington, D.C. Draft, December 2006.
USEPA, 2014. Protection of Downstream Waters in Water Quality Standards: Frequently Asked
Questions. U.S. Environmental Protection Agency, Office of Water. Washington, D.C. EPA/820-F-14-001. June 2014.
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A-5
Table A-1 (cont’d). 2011 MRLC Land Use Distribution of Impaired HUC-12s & Drainage Areas
Landuse
Impaired Watershed (06010207____) or Waterbody Drainage Area (DA)
Ernies Creek DA (in 0403)
Scarboro Creek DA (in 0404)
Code Description [acres] [%] [acres] [%]
11 Open Water 0 0.00 3 0.30
21 Developed, Open Space 491 30.2 104 10.6
22 Developed, Low Intensity 538 33.0 130 13.3
23 Developed, Medium Intensity 270 16.6 152 15.6
24 Developed, High Intensity 99 6.08 23 2.35
31 Barren Land (Rock/Sand/Clay) 0 0.03 0 0.00
41 Deciduous Forest 155 9.52 405 41.4
42 Evergreen Forest 25 1.54 43 4.39
43 Mixed Forest 29 1.79 24 2.41
52 Shrub/Scrub 0 0.00 4 0.46
71 Grassland/Herbaceous 6 0.40 19 1.98
81 Pasture/Hay 0 0.00 53 5.42
82 Cultivated Crops 0 0.00 0 0.00
90 Woody Wetlands 15 0.90 17 1.73
95 Emergent Herbaceous Wetlands 0 0.00 0 0.00
Subtotal – Urban 1,398 85.8 409 41.9
Subtotal – Agriculture 0 0.00 53 5.42
Subtotal - Forest 231 14.2 515 52.7
Total 1,629 100 977 100
E. coli TMDL Lower Clinch River Watershed (HUC 06010207)
9/21/17 - Final Page A-6 of A-6
A-6
Table A-1 (cont’d). 2011 MRLC Land Use Distribution of Impaired HUC-12s & Drainage Areas
Landuse
Impaired Watershed (06010207____) or Waterbody Drainage Area (DA)
Coal Creek DA (in 0401)
Byrams Creek DA (in 0402)
Code Description [acres] [%] [acres] [%]
11 Open Water 7 0.03 1 0.02
21 Developed, Open Space 1,903 8.18 366 5.56
22 Developed, Low Intensity 851 3.66 83 1.25
23 Developed, Medium Intensity 378 1.63 4 0.06
24 Developed, High Intensity 80 0.35 0 0.00
31 Barren Land (Rock/Sand/Clay) 67 0.29 1 0.02
41 Deciduous Forest 15,660 67.3 3,681 56.0
42 Evergreen Forest 550 2.36 447 6.79
43 Mixed Forest 1,529 6.57 592 8.99
52 Shrub/Scrub 291 1.25 79 1.20
71 Grassland/Herbaceous 1,231 5.29 566 8.60
81 Pasture/Hay 635 2.73 727 11.1
82 Cultivated Crops 0 0.00 0 0.00
90 Woody Wetlands 75 0.32 32 0.48
95 Emergent Herbaceous Wetlands 6 0.02 0 0.00
Subtotal – Urban 3,212 13.8 452 6.87
Subtotal – Agriculture 635 2.73 727 11.1
Subtotal - Forest 19,416 83.5 5,398 82.1
Total 23,262 100 6,578 100
E. coli TMDL Lower Clinch River Watershed (HUC 06010207)
9/21/17 - Final Page B-1 of B-18
B-1
APPENDIX B
Water Quality Monitoring Data
for the Lower Clinch River Watershed
E. coli TMDL Lower Clinch River Watershed (HUC 06010207)
9/21/17 - Final Page B-2 of B-18
B-2
The location of monitoring stations in the Lower Clinch River Watershed is shown in Figure 5. Monitoring data recorded by TDEC at these stations are tabulated in Table B-1. Monitoring data recorded by DOE at these stations are tabulated in Table B-2. Exceedances of the appropriate E. coli standard are shown in red.
Table B-1. TDEC Water Quality Monitoring Data
Monitoring Station Date E. coli
[CFU/100mL]
BEAVE003.5KN
23-Feb-99 147
23-Mar-99 147
26-Apr-99 79
03-Jun-99 261
27-Jul-99 172
28-Jul-99 196
24-Aug-99 187
30-Sep-99 250
25-Oct-99 88
02-Dec-99 179
25-Jan-00 66
04-Mar-04 488
13-Apr-04 >2419
04-May-04 1553
25-May-04 86
29-Jun-04 313
14-Jul-04 770
03-Aug-04 435
13-Sep-04 127
27-Oct-04 225
14-Dec-04 866
11-Jan-05 613
16-May-06 93
23-Jul-08 72
30-Jul-08 248
06-Aug-08 89
13-Aug-08 285
20-Aug-08 78
25-Jul-13 260
01-Aug-13 155
06-Aug-13 115
13-Aug-13 115
15-Aug-13 111
E. coli TMDL Lower Clinch River Watershed (HUC 06010207)
9/21/17 - Final Page B-3 of B-18
B-3
Table B-1 (cont’d). TDEC Water Quality Monitoring Data
Monitoring Station Date E. coli
[CFU/100mL]
BEAVE024.7KN
04-Mar-04 261
13-Apr-04 >2419
04-May-04 1203
25-May-04 613
29-Jun-04 649
14-Jul-04 1414
03-Aug-04 517
13-Sep-04 365
27-Oct-04 649
14-Dec-04 2419
11-Jan-05 548
16-May-06 299
23-Jul-08 162
30-Jul-08 461
06-Aug-08 173
13-Aug-08 613
20-Aug-08 154
25-Jul-13 387
01-Aug-13 921
06-Aug-13 299
13-Aug-13 488
15-Aug-13 236
BEAVE040.1KN
23-Feb-99 148
23-Mar-99 1046
26-Apr-99 411
03-Jun-99 1733
27-Jul-99 613
28-Jul-99 5779
24-Aug-99 >2419
30-Sep-99 248
25-Oct-99 548
06-Dec-99 980
25-Jan-00 144
E. coli TMDL Lower Clinch River Watershed (HUC 06010207)
9/21/17 - Final Page B-4 of B-18
B-4
Table B-1 (cont’d). TDEC Water Quality Monitoring Data
Monitoring Station Date E. coli
[CFU/100mL]
BEAVE040.1KN (cont’d)
23-Jul-08 120
30-Jul-08 770
06-Aug-08 248
13-Aug-08 727
20-Aug-08 41
25-Jul-13 548
01-Aug-13 1414
06-Aug-13 613
13-Aug-13 1300
15-Aug-13 2420
BUFFA000.7AN
25-Feb-99 75
24-Jul-03 577
27-Aug-03 121
09-Sep-03 387
18-Sep-03 114
24-Sep-03 980
16-Oct-03 140
21-Oct-03 99
27-Oct-03 727
30-Oct-03 105
14-Sep-04 248
26-Oct-04 291
21-Dec-04 214
26-Jan-05 108
09-Mar-05 411
27-Apr-05 517
18-May-05 517
12-Jun-05 179
02-Aug-05 770
01-Apr-10 157
30-Sep-10 461
01-Nov-10 435
29-Nov-10 285
29-Dec-10 260
E. coli TMDL Lower Clinch River Watershed (HUC 06010207)
9/21/17 - Final Page B-5 of B-18
B-5
Table B-1 (cont’d). TDEC Water Quality Monitoring Data
Monitoring Station Date E. coli
[CFU/100mL]
BULLR005.2AN
25-Feb-99 35
20-Apr-99 109
22-Jun-99 579
18-Aug-99 727
28-Dec-99 33
27-Sep-01 548
30-Oct-01 112
12-Dec-01 1203
15-Jul-02 816
07-Oct-02 517
30-Jul-13 261
05-Aug-13 155
08-Aug-13 185
15-Aug-13 291
26-Aug-13 326
BULLR016.2KN
06-Dec-99 146
27-Sep-01 517
30-Oct-01 71
12-Dec-01 1733
15-Jul-02 687
07-Oct-02 291
30-Jul-13 727
05-Aug-13 260
08-Aug-13 980
15-Aug-13 179
26-Aug-13 345
BULLR031.1UN
12-Dec-01 866
15-Jul-02 921
30-Jul-13 308
05-Aug-13 488
08-Aug-13 >2420
15-Aug-13 687
26-Aug-13 199
E. coli TMDL Lower Clinch River Watershed (HUC 06010207)
9/21/17 - Final Page B-6 of B-18
B-6
Table B-1 (cont’d). TDEC Water Quality Monitoring Data
Monitoring Station Date E. coli
[CFU/100mL]
BYRAM000.4AN
24-Jul-03 1733
27-Aug-03 285
09-Sep-03 488
18-Sep-03 387
24-Sep-03 1986
16-Oct-03 488
21-Oct-03 308
23-Oct-03 249
27-Oct-03 2419
30-Oct-03 1046
14-Sep-04 242
26-Oct-04 435
21-Dec-04 48
26-Jan-05 49
09-Mar-05 34
27-Apr-05 >2419
18-May-05 387
21-Jun-05 250
02-Aug-05 73
10-Jul-08 >2419
17-Jul-08 276
21-Jul-08 214
24-Jul-08 228
30-Jul-08 326
05-Aug-08 249
01-Apr-10 6
29-Apr-10 173
26-May-10 345
30-Jun-10 517
26-Jul-10 649
05-Aug-10 517
10-Aug-10 219
24-Aug-10 1414
26-Aug-10 579
E. coli TMDL Lower Clinch River Watershed (HUC 06010207)
9/21/17 - Final Page B-7 of B-18
B-7
Table B-1 (cont’d). TDEC Water Quality Monitoring Data
Monitoring Station Date E. coli
[CFU/100mL]
BYRAM000.4AN (cont’d)
02-Sep-10 248
30-Sep-10 687
01-Nov-10 192
29-Nov-10 140
29-Dec-10 27
30-Jul-13 378
05-Aug-13 613
08-Aug-13 435
15-Aug-13 613
26-Aug-13 579
COAL001.2AN
25-Feb-99 361
20-Apr-99 148
22-Jun-99 76
18-Aug-99 81
28-Dec-99 22
24-Jul-03 1203
27-Aug-03 141
09-Sep-03 292
18-Sep-03 131
24-Sep-03 >2419
16-Oct-03 150
21-Oct-03 84
23-Oct-03 58
27-Oct-03 2419
30-Oct-03 82
10-Jul-08 1203
17-Jul-08 104
21-Jul-08 127
24-Jul-08 158
30-Jul-08 866
05-Aug-08 219
20-Aug-08 99
17-Sep-08 23
16-Oct-08 99
19-Nov-08 105
E. coli TMDL Lower Clinch River Watershed (HUC 06010207)
9/21/17 - Final Page B-8 of B-18
B-8
Table B-1 (cont’d). TDEC Water Quality Monitoring Data
Monitoring Station Date E. coli
[CFU/100mL]
COAL001.2AN (cont’d)
14-Jan-09 1986
19-Feb-09 10
10-Mar-09 649
22-Apr-09 770
13-May-09 48
02-Jun-09 199
07-Jul-09 1986
28-Jul-09 272
30-Jul-13 687
05-Aug-13 980
08-Aug-13 1986
15-Aug-13 649
26-Aug-13 365
COAL010.6AN
25-Feb-99 155
24-Jul-03 85
27-Aug-03 259
09-Sep-03 687
18-Sep-03 687
24-Sep-03 299
16-Oct-03 96
21-Oct-03 214
23-Oct-03 155
27-Oct-03 980
30-Oct-03 57
10-Jul-08 >2419
17-Jul-08 236
21-Jul-08 285
24-Jul-08 150
30-Jul-08 1300
05-Aug-08 248
30-Jul-13 30
05-Aug-13 194
08-Aug-13 228
15-Aug-13 93
26-Aug-13 141
E. coli TMDL Lower Clinch River Watershed (HUC 06010207)
9/21/17 - Final Page B-9 of B-18
B-9
Table B-1 (cont’d). TDEC Water Quality Monitoring Data
Monitoring Station Date E. coli
[CFU/100mL]
EFPOP006.9RO
18-Aug-08 152
16-Sep-08 147
13-Oct-08 157
19-Nov-08 127
16-Dec-08 345
13-Jan-09 161
11-Feb-09 122
12-Mar-09 113
08-Apr-09 86
05-May-09 488
09-Jun-09 185
08-Jul-09 121
25-Jul-13 108
01-Aug-13 488
06-Aug-13 138
13-Aug-13 365
15-Aug-13 345
EFPOP008.6AN
30-Jul-08 91
04-Aug-08 148
07-Aug-08 187
12-Aug-08 170
13-Aug-08 68
18-Aug-08 115
16-Sep-08 548
13-Oct-08 172
19-Nov-08 138
16-Dec-08 345
13-Jan-09 50
11-Feb-09 41
12-Mar-09 158
08-Apr-09 138
05-May-09 517
09-Jun-09 980
08-Jul-09 411
05-Jul-11 770
E. coli TMDL Lower Clinch River Watershed (HUC 06010207)
9/21/17 - Final Page B-10 of B-18
B-10
Table B-1 (cont’d). TDEC Water Quality Monitoring Data
Monitoring Station Date E. coli
[CFU/100mL]
GRASS000.3KN
23-Jul-08 1414
30-Jul-08 345
06-Aug-08 411
13-Aug-08 157
20-Aug-08 261
25-Jul-13 517
01-Aug-13 435
06-Aug-13 365
13-Aug-13 548
15-Aug-13 291
HINDS000.7AN
25-Feb-99 131
20-Apr-99 236
22-Jun-99 291
18-Aug-99 186
28-Dec-99 27
24-Jul-03 1986
27-Aug-03 1553
09-Sep-03 687
24-Sep-03 1733
16-Oct-03 140
21-Oct-03 649
23-Oct-03 1414
27-Oct-03 1120
30-Oct-03 411
14-Sep-04 365
26-Oct-04 172
21-Dec-04 91
26-Jan-05 93
09-Mar-05 130
27-Apr-05 649
18-May-05 152
21-Jun-05 727
02-Aug-05 387
E. coli TMDL Lower Clinch River Watershed (HUC 06010207)
9/21/17 - Final Page B-11 of B-18
B-11
Table B-1 (cont’d). TDEC Water Quality Monitoring Data
Monitoring Station Date E. coli
[CFU/100mL]
HINDS000.7AN (cont’d)
10-Jul-08 1733
17-Jul-08 770
21-Jul-08 1300
24-Jul-08 1120
30-Jul-08 770
05-Aug-08 204
01-Apr-10 126
29-Apr-10 548
26-May-10 980
30-Jun-10 548
26-Jul-10 921
05-Aug-10 921
10-Aug-10 517
24-Aug-10 461
26-Aug-10 435
02-Sep-10 980
30-Sep-10 548
01-Nov-10 345
29-Nov-10 210
29-Dec-10 54
30-Jul-13 613
05-Aug-13 517
08-Aug-13 461
15-Aug-13 411
26-Aug-13 687
HINDS06.8AN
25-Feb-99 55
24-Jul-03 1203
27-Aug-03 144
09-Sep-03 272
18-Sep-03 105
24-Sep-03 >2419
16-Oct-03 387
21-Oct-03 86
23-Oct-03 130
27-Oct-03 687
30-Oct-03 59
E. coli TMDL Lower Clinch River Watershed (HUC 06010207)
9/21/17 - Final Page B-12 of B-18
B-12
Table B-1 (cont’d). TDEC Water Quality Monitoring Data
Monitoring Station Date E. coli
[CFU/100mL]
HINDS006.8AN (cont’d)
14-Sep-04 184
26-Oct-04 99
21-Dec-04 61
26-Jan-05 53
09-Mar-05 77
27-Apr-05 548
18-May-05 179
21-Jun-05 179
02-Aug-05 104
10-Jul-08 548
17-Jul-08 76
21-Jul-08 91
24-Jul-08 172
30-Jul-08 110
05-Aug-08 124
01-Apr-10 25
29-Apr-10 285
26-May-10 326
30-Jun-10 435
26-Jul-10 387
05-Aug-10 170
10-Aug-10 236
24-Aug-10 308
26-Aug-10 326
02-Sep-10 99
30-Sep-10 727
01-Nov-10 115
29-Nov-10 104
29-Dec-10 127
05-Aug-13 387
08-Aug-13 313
15-Aug-13 517
26-Aug-13 548
HINDS014.1AN
25-Feb-99 68
24-Jul-03 727
27-Aug-03 260
E. coli TMDL Lower Clinch River Watershed (HUC 06010207)
9/21/17 - Final Page B-13 of B-18
B-13
Table B-1 (cont’d). TDEC Water Quality Monitoring Data
Monitoring Station Date E. coli
[CFU/100mL]
HINDS014.1AN (cont’d)
09-Sep-03 316
18-Sep-03 173
24-Sep-03 1553
16-Oct-03 158
21-Oct-03 147
23-Oct-03 125
27-Oct-03 980
30-Oct-03 194
14-Sep-04 411
26-Oct-04 119
21-Dec-04 99
26-Jan-05 113
09-Mar-05 105
27-Apr-05 770
18-May-05 228
21-Jun-05 291
02-Aug-05 345
10-Jul-08 >2419
17-Jul-08 345
21-Jul-08 326
24-Jul-08 115
30-Jul-08 308
05-Aug-08 206
01-Apr-10 57
29-Apr-10 378
26-May-10 225
30-Jun-10 291
26-Jul-10 308
05-Aug-10 150
10-Aug-10 138
24-Aug-10 435
26-Aug-10 249
02-Sep-10 155
30-Sep-10 238
01-Nov-10 179
29-Nov-10 308
29-Dec-10 131
E. coli TMDL Lower Clinch River Watershed (HUC 06010207)
9/21/17 - Final Page B-14 of B-18
B-14
Table B-1 (cont’d). TDEC Water Quality Monitoring Data
Monitoring Station Date E. coli
[CFU/100mL]
HINDS014.1AN (cont’d)
30-Jul-13 517
05-Aug-13 461
08-Aug-13 488
15-Aug-13 238
26-Aug-13 687
HINES000.2KN
04-Mar-04 147
13-Apr-04 >2419
04-May-04 488
25-May-04 921
29-Jun-04 1300
14-Jul-04 >2419
03-Aug-04 1203
13-Sep-04 687
27-Oct-04 461
14-Dec-04 517
11-Jan-05 548
16-May-06 687
23-Aug-06 228
23-Jul-08 613
30-Jul-08 727
06-Aug-08 770
13-Aug-08 727
20-Aug-08 2419
25-Jul-13 365
01-Aug-13 649
06-Aug-13 649
13-Aug-13 921
15-Aug-13 488
KNOB000.3KN
04-Mar-04 178
13-Apr-04 >2419
04-May-04 1414
25-May-04 228
29-Jun-04 365
14-Jul-04 >2419
03-Aug-04 517
E. coli TMDL Lower Clinch River Watershed (HUC 06010207)
9/21/17 - Final Page B-15 of B-18
B-15
Table B-1 (cont’d). TDEC Water Quality Monitoring Data
Monitoring Station Date E. coli
[CFU/100mL]
KNOB000.3KN (cont’d)
13-Sep-04 192
27-Oct-04 980
14-Dec-04 131
11-Jan-05 173
16-May-06 131
23-Jul-08 687
30-Jul-08 225
06-Aug-08 135
13-Aug-08 126
20-Aug-08 105
25-Jul-13 687
KNOB000.8KN
01-Aug-13 261
06-Aug-13 129
13-Aug-13 344
15-Aug-13 326
MEADO000.2KN
04-Mar-04 165
13-Apr-04 >2419
04-May-04 548
25-May-04 816
29-Jun-04 921
14-Jul-04 >2419
03-Aug-04 579
13-Sep-04 214
27-Oct-04 2419
14-Dec-04 178
11-Jan-05 1300
16-May-06 345
23-Jul-08 79
30-Jul-08 308
06-Aug-08 276
13-Aug-08 75
20-Aug-08 23
25-Jul-13 2420
01-Aug-13 517
06-Aug-13 435
13-Aug-13 517
15-Aug-13 1046
E. coli TMDL Lower Clinch River Watershed (HUC 06010207)
9/21/17 - Final Page B-16 of B-18
B-16
Table B-1 (cont’d). TDEC Water Quality Monitoring Data
Monitoring Station Date E. coli
[CFU/100mL]
NFBUL000.1UN
27-Sep-01 276
30-Oct-01 104
12-Dec-01 1414
15-Jul-02 345
07-Oct-02 238
30-Jul-13 172
05-Aug-13 328
08-Aug-13 488
15-Aug-13 291
26-Aug-13 108
PLUMB000.3KN
04-Mar-04 249
13-Apr-04 2419
04-May-04 517
25-May-04 231
29-Jun-04 178
14-Jul-04 613
03-Aug-04 365
13-Sep-04 214
27-Oct-04 2419
14-Dec-04 2419
11-Jan-05 1203
16-May-06 157
23-Jul-08 211
30-Jul-08 345
06-Aug-08 194
13-Aug-08 109
20-Aug-08 109
25-Jul-13 411
01-Aug-13 166
06-Aug-13 107
13-Aug-13 172
15-Aug-13 210
WILLO000.5KN
04-Mar-04 121
13-Apr-04 >2419
04-May-04 178
25-May-04 1733
E. coli TMDL Lower Clinch River Watershed (HUC 06010207)
9/21/17 - Final Page B-17 of B-18
B-17
Table B-1 (cont’d). TDEC Water Quality Monitoring Data
Monitoring Station Date E. coli
[CFU/100mL]
WILLO000.5KN (cont’d)
14-Jul-04 1203
03-Aug-04 517
13-Sep-04 2419
27-Oct-04 579
14-Dec-04 197
11-Jan-05 356
16-May-06 157
23-Jul-08 214
30-Jul-08 201
06-Aug-08 219
13-Aug-08 249
20-Aug-08 131
25-Jul-13 365
01-Aug-13 260
06-Aug-13 308
13-Aug-13 365
15-Aug-13 461
E. coli TMDL Lower Clinch River Watershed (HUC 06010207)
9/21/17 - Final Page B-18 of B-18
B-18
Table B-2. DOE Water Quality Monitoring Data
Monitoring Station Site # Date E. coli
[CFU/100mL]
Scarboro Creek 8
12/4/1997 135
6/15/1998 411
10/8/1998 1414
6/22/1999 12
11/8/1999 61
6/8/2000 101
10/10/2000 488
4/30/2001 157
10/8/2001 649
10/7/2002 1046
4/24/2007 115
9/20/2007 326
9/20/2007 261
6/2/2008 613
10/16/2008 435
Ernie’s Creek 23
6/22/1999 76
11/8/1999 219
6/19/2000 >2419
10/9/2000 75
5/7/2001 2419
5/1/2007 328
9/24/2007 2419
6/26/2008 249
10/15/2008 248
E. coli TMDL Lower Clinch River Watershed (HUC 06010207)
9/21/17 - Final Page C-1 of C-9
C-1
APPENDIX C
Load Duration Curve Development
and
Determination of Daily Loading
E. coli TMDL Lower Clinch River Watershed (HUC 06010207)
9/21/17 - Final Page C-2 of C-9
C-2
The TMDL process quantifies the amount of a pollutant that can be assimilated in a waterbody, identifies the sources of the pollutant, and recommends regulatory or other actions to be taken to achieve compliance with applicable water quality standards based on the relationship between pollution sources and in-stream water quality conditions. A TMDL can be expressed as the sum of all point source loads (Waste Load Allocations), nonpoint source loads (Load Allocations), and an appropriate margin of safety (MOS) that takes into account any uncertainty concerning the relationship between effluent limitations and water quality:
TMDL = WLAs + LAs + MOS
The objective of a TMDL is to allocate loads among all of the known pollutant sources throughout a watershed so that appropriate control measures can be implemented and water quality standards achieved. 40 CFR §130.2 (i) (http://www.gpo.gov/fdsys/pkg/CFR-2011-title40-vol22/pdf/CFR-2011-title40-vol22-sec130-2.pdf) states that TMDLs can be expressed in terms of mass per time, toxicity, or other appropriate measure.
C.1 Development of TMDLs
E. coli TMDLs, WLAs, and LAs were developed for impaired subwatersheds and drainage areas in the Lower Clinch River Watershed using Load Duration Curves (LDCs). Daily loads for TMDLs, WLAs, and LAs are expressed as a function of daily mean in-stream flow (daily loading function).
C.1.1 Development of Flow Duration Curves
A flow duration curve is a cumulative frequency graph, constructed from historic flow data at a particular location, that represents the percentage of time a particular flow is equaled or exceeded. Flow duration curves are developed for a waterbody from daily discharges of flow over an extended period of record. In general, there is a higher level of confidence that curves derived from data over a long period of record accurately represent the entire range of flow. The preferred method of flow duration curve computation uses daily mean data from USGS continuous-record stations (http://waterdata.usgs.gov/tn/nwis/sw ) located on the waterbody of interest. For ungaged streams, alternative methods must be used to estimate daily mean flow. These include: 1) regression equations (using drainage area as the independent variable) developed from continuous record stations in the same ecoregion; 2) drainage area extrapolation of data from a nearby continuous-record station of similar size and topography; and 3) calculation of daily mean flow using a dynamic computer model, such as the Windows version of Hydrologic Simulation Program - Fortran (WinHSPF).
Flow duration curves for impaired waterbodies in the Lower Clinch River Watershed were derived from WinHSPF hydrologic simulations based on parameters derived from calibrations at several USGS gaging stations (see Appendix D for details of calibration). For example, a flow duration curve for Coal Creek at mile 1.2 was constructed using simulated daily mean flow for the period from 1/1/98 through 12/31/14 (RM 1.2 corresponds to the location of monitoring station COAL001.2AN). This flow duration curve is shown in Figure C-1 and represents the cumulative distribution of daily discharges arranged to show percentage of time specific flows were exceeded during the period of record (the highest daily mean flow during this period is exceeded 0% of the time and the lowest daily mean flow is equaled or exceeded 100% of the time). Flow duration curves for other impaired waterbodies were derived using a similar procedure.
E. coli TMDL Lower Clinch River Watershed (HUC 06010207)
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C-3
C.1.2 Development of Load Duration Curves and TMDLs
When a water quality target concentration is applied to the flow duration curve, the resulting load duration curve (LDC) represents the allowable pollutant loading in a waterbody over the entire range of flow. Pollutant monitoring data, plotted on the LDC, provides a visual depiction of stream water quality as well as the frequency and magnitude of any exceedances. Load duration curve intervals can be grouped into several broad categories or zones, in order to provide additional insight about conditions and patterns associated with the impairment. For example, the duration curve could be divided into five zones: high flows (exceeded 0-10% of the time), moist conditions (10-40%), median or mid-range flows (40-60%), dry conditions (60-90%), and low flows (90-100%). Impairments observed in the low flow zone typically indicate the influence of point sources, while those further left on the LDC (representing zones of higher flow) predominantly reflect potential nonpoint source contributions (Stiles, 2003).
E. coli load duration curves for impaired waterbodies in the Lower Clinch River Watershed were developed from the flow duration curves developed in Section C.1.1, E. coli target concentrations, and available water quality monitoring data. Load duration curves and required load reductions were developed using the following procedure (Coal Creek at RM 1.2 is shown as an example):
1. A target load duration curve (LDC) was generated for Coal Creek by applying the E. coli
target concentration of 941 CFU/100 mL to each of the ranked flows used to generate the flow duration curve (ref.: Section D.1) and plotting the results. The E. coli target maximum load corresponding to each ranked daily mean flow is:
(Target Load)Coal Creek = (941 CFU/100 mL) x (Q) x (UCF)
where: Target Load = TMDL (CFU/day)
Q = daily instream mean flow (cfs) UCF = the required unit conversion factor (2.44x107)
TMDL = (2.30x1010) x (Q) CFU/day
2. Daily loads were calculated for each of the water quality samples collected at monitoring station COAL001.2AN (ref.: Table B-1) by multiplying the sample concentration by the daily mean flow for the sampling date and the required unit conversion factor. COAL001.2AN was selected for LDC analysis because it has a longer period of record and multiple exceedances of the target concentration.
Note: In order to be consistent for all analyses, the derived daily mean flow was
used to compute sampling data loads, even if measured (“instantaneous”) flow data were available for some sampling dates.
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3. Using the flow duration curves developed in C.1.1, the “percent of days the flow was exceeded” (PDFE) was determined for each sampling event. Each sample load was then plotted on the load duration curves developed in Step 1 according to the PDFE. The resulting E. coli load duration curve for Coal Creek is shown in Figure C-2.
LDCs of other impaired waterbodies were derived in a similar manner and are shown in Appendix E.
C.2 Development of WLAs & LAs As previously discussed, a TMDL can be expressed as the sum of all point source loads (WLAs), nonpoint source loads (LAs), and an appropriate margin of safety (MOS) that takes into account any uncertainty concerning the relationship between effluent limitations and water quality:
TMDL = WLAs + LAs + MOS Expanding the terms:
TMDL = [WLAs]WWTP + [WLAs]MS4 + [WLAs]CAFO + [LAs]DS+ [LAs]SW + MOS For E. coli TMDLs in each impaired subwatershed or drainage area, WLA terms include:
[WLAs]WWTP is the allowable load associated with discharges of NPDES permitted WWTPs located in impaired subwatersheds or drainage areas. Since NPDES permits for these facilities specify that treated wastewater must meet in-stream water quality standards at the point of discharge, no additional load reduction is required. WLAs for WWTPs are calculated from the mean daily facility flow (expressed as “qm”) and the Daily Maximum permit limit. A future growth term for potential new WWTPs is included.
[WLAs]CAFO is the allowable load for all CAFOs in an impaired subwatershed or drainage area. All wastewater discharges from a CAFO to waters of the state of Tennessee are prohibited, except when either chronic or catastrophic rainfall events cause an overflow of process wastewater from a facility properly designed, constructed, maintained, and operated to contain:
o All process wastewater resulting from the operation of the CAFO (such as wash water, parlor water, watering system overflow, etc.); plus,
o All runoff from a 25-year, 24-hour rainfall event for the existing CAFO or new dairy or cattle CAFOs; or all runoff from a 100-year, 24-hour rainfall event for a new swine or poultry CAFO.
Therefore, a WLA of zero has been assigned to this class of facilities.
[WLAs]MS4 is the allowable E. coli load for discharges from MS4s. E. coli loading from MS4s is the result of buildup/wash-off processes associated with storm events.
LA terms include:
[LAs]DS is the allowable E. coli load from “other direct sources”. These sources include leaking septic systems, illicit discharges, and animals access to streams. The LA specified for all sources of this type is zero CFU/day (or to the maximum extent feasible).
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[LAs]SW represents the allowable E. coli loading from nonpoint sources indirectly going to surface waters from all land use areas (except areas covered by a MS4 permit) as a result of the buildup/wash-off processes associated with storm events (i.e., precipitation induced).
Since [WLAs]CAFO = 0 and [LAs]DS = 0, the expression relating TMDLs to precipitation-based point and nonpoint sources may be simplified to:
TMDL – MOS = [WLAs]WWTP + [WLAs]MS4 + [LAs]SW As stated in Section 8.5, an explicit MOS, equal to 10% of the E. coli water quality targets (ref.: Section 5.0), was utilized for determination of the percent load reductions necessary to achieve WLAs and LAs:
Instantaneous Maximum (lake, reservoir, State Scenic River, Exceptional Tennessee Waters):
C.2.1 Daily Load Calculation Since WWTPs discharge must comply with instream water quality criteria (TMDL target) at the point of discharge, WLAs for WWTPs are expressed as a function of the mean daily facility flow (“q”) and the Daily Maximum permit limit. In addition, WLAs for MS4s and LAs for precipitation-based nonpoint sources are equal on a per unit area basis and may be expressed as the daily allowable load per unit area (acre) resulting from a decrease in in-stream E. coli concentrations to TMDL target values minus MOS:
WLA[MS4] = LA = {TMDL – MOS – WLA[WWTPs]} / DA
where: DA = waterbody drainage area (acres)
Using Coal Creek as an example:
TMDLCoal Creek = (941 CFU/100 mL) x (Q) x (UCF)
TMDL = 2.30x1010 x Q
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MOSCoal Creek = TMDL x 0.10 = 2.30x109 x Q
MOS = (2.30x109) x (Q) CFU/day
WLA[WWTFs]Coal Creek = qm (cfs) x 941 (CFU/100 mL) x UCF
WLA[WWTFs]Coal Creek = (2.30x1010) x (qm) CFU/day
For cases in which there is a WWTP currently discharging to the waterbody, the design flow (qd) will be used in the equation because the mean daily facility flow can be as high as design flow (qd):
WLA[MS4]Coal Creek = LACoal Creek
= {TMDL – MOS – WLA[WWTPs]d} / DA
= {(2.30x1010 x Q) – (2.30x109 x Q) – (2.30x1010 x qd)} / (23,016)
WLA[MS4]Coal Creek = LACoal Creek
= [8.994x105 x Q] – [9.99x105 x qd]
For cases in which there is no WWTP currently discharging to the waterbody, the variable qd will be retained in the equation as a placeholder for any future WWTPs. Using Willow Fork as an example:
WLA[MS4]Willow Fork = LAWillow Fork
= {TMDL – MOS – WLA[WWTPs]d} / DA
= {(2.30x1010 x Q) – (2.30x109 x Q) – (2.30x1010 x qd)} / (4537.5)
WLA[MS4]Willow Fork = LAWillow Fork = [4.562x106 x Q] – [5.07x106 x qd]
TMDLs, WLAs, & LAs for other impaired subwatersheds and drainage areas were derived in a similar manner and are summarized in Table C-1.
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Figure C-1. Flow Duration Curve for Coal Creek at RM 1.2
Hinds Creek d,e TN06010207016_2000 (8.242 x 105 x Q)
– (9.158 x 105 x qd) (8.242 x 105 x Q)
– (9.158 x 105 x qd)
Hinds Creek d,e TN06010207016_3000 (1.979 x 106 x Q)
– (2.198 x 106 x qd) (1.979 x 106 x Q)
– (2.198 x 106 x qd)
Buffalo Creek d TN06010207016_0100 (2.073 x 106 x Q)
– (2.303 x 106 x qd) (2.073 x 106 x Q)
– (2.303 x 106 x qd)
Byrams Creek d,e TN06010207016_0200 (3.147 x 106 x Q)
– (3.497 x 106 x qd) (3.147 x 106 x Q)
– (3.497 x 106 x qd)
0403 Ernies Creek d,e TN06010207006T_1100 2.3 x 1010 x Q 2.3 x 109 x Q (2.3x1010 x qm) (1.271 x 107 x Q)
– (1.412 x 107 x qd) (1.271 x 107 x Q)
– (1.412 x 107 x qd)
0404 Scarboro Creek d,e TN06010207006T_0900 2.3 x 1010 x Q 2.3 x 109 x Q (2.3x1010 x qm) (2.119 x 107 x Q)
– (2.354 x 107 x qd) (2.119 x 107 x Q)
– (2.354 x 107 x qd)
Notes: Q = Mean Daily In-stream Flow (cfs). qm = Mean Daily WWTP Flow (cfs) qd = Facility (WWTP) Design Flow (cfs) a. WLAs for WWTPs are expressed as E. coli loads (CFU/day). All current and future WWTPs must meet water quality standards as specified in their NPDES permit. b. Applies to any MS4 discharge loading in the subwatershed. Future MS4s will be assigned waste load allocations (WLAs) consistent with load allocations (LAs) assigned to precipitation induced
nonpoint sources. Compliance is achieved by meeting in-stream single-sample E. coli concentrations of ≤ 941 CFU/100 mL (or 487 CFU/100 mL for lakes, reservoirs, State Scenic Rivers, or Exceptional Tennessee Waters).
c. WLAs and LAs expressed as a “per acre” load are calculated based on the drainage area at the pour point of the HUC-12 subwatershed or drainage area (see Table A-1). As regulated MS4 area increases (due to future growth and/or new MS4 designation), unregulated LA area decreases by an equivalent amount. The sum will continue to equal total subwatershed area.
d. Waterbody Drainage Area (DA) is not coincident with HUC-12(s). e. No WWTPs currently discharging into or upstream of the waterbody. (WLA[WWTPs] Expression is future growth term for new WWTPs.) f. No MS4s currently located in the subwatershed drainage area. (Expression is future growth term for expanding or newly designated MS4s.)
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APPENDIX D
Hydrodynamic Modeling Methodology
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D.1 Model Selection
The Windows version of Hydrologic Simulation Program - Fortran (HSPF) was selected for flow simulation of pathogen-impaired waters in the subwatersheds of the Lower Clinch River Watershed. HSPF is a watershed model capable of performing flow routing through stream reaches.
D.2 Model Set Up
The Lower Clinch River Watershed was delineated into subwatersheds in order to facilitate model hydrologic calibration. Boundaries were constructed so that subwatershed “pour points” coincided with HUC-12 delineations, 303(d)-listed waterbodies, and water quality monitoring stations. Watershed delineation was based on the NHD stream coverage and Digital Elevation Model (DEM) data. This discretization facilitates simulation of daily flows at water quality monitoring stations.
Several computer-based tools were utilized to generate input data for the WinHSPF model. ArcMap and BASINS, GIS tools, were used to display, analyze, and compile available information to support hydrology model simulations for selected subwatersheds. This information includes land use categories, point source dischargers, soil types and characteristics, population data (human and livestock), and stream characteristics.
Weather data from multiple meteorological stations were available for the time period from January 1970 through December 2014. Meteorological data for a selected 11- to 16-year period were used for all simulations. The first year of this period was used for model stabilization with simulation data from the subsequent 10- to 15-year period used for TMDL analysis. The length of the simulation varied depending on the period of record of the monitoring data for the selected waterbody. Occasionally, a period of less than 10 years was used for calibration because either (1) the gage did not have a full 10-year period of continuous record; or, (2) unusual weather events (e.g. drought or flood) precluded calibration for a 10-year period.
An important factor influencing model results is the precipitation data used for the simulation. For the Lower Clinch River watershed, a grid was created of cells that were 0.1° (latitude) x 0.1° (longitude) (approximately 6.9 mi. x 5.6 mi.).Total hourly precipitation for each grid cell for the desired time period was downloaded from the NASA website using their Giovanni tool (https://giovanni.sci.gsfc.nasa.gov/giovanni/). For each individual model, the total hourly precipitation data for each of the grid cells within the drainage area of the model were averaged to create a unique precipitation record for that drainage area. For parameters other than precipitation, meteorological data from the station at the Knoxville airport were used.
D.3 Model Calibration
Hydrologic calibration of the watershed model involves comparison of simulated streamflow to historic streamflow data from USGS stream gaging stations for the same period of time. One USGS continuous record station located in the Lower Clinch River Watershed was selected as the basis of the hydrology calibration. Station 03535000 is located on Bullrun Creek near Halls Crossroads, TN, within Level IV ecoregions 67f and 67i and has a drainage area of 66.9 square miles.
Initial values for hydrologic variables were taken from an EPA developed default data set. During the calibration process, model parameters were adjusted within reasonable constraints until acceptable agreement was achieved between simulated and observed streamflow. Model parameters adjusted include: evapotranspiration, infiltration, upper and lower zone storage, groundwater storage, recession, losses to the deep groundwater system, and interflow discharge.
The results of the hydrologic calibration for Bullrun Creek near Halls Crossroads, TN, (USGS Station 03535000) are shown in Table D-1 and Figures D-1 and D-2.
Figure D-2. 5-Year Hydrologic Comparison: Bullrun Creek, USGS 03535000
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APPENDIX E
Source Area Implementation Strategy
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All impaired waterbodies and corresponding HUC-12 subwatersheds or drainage areas have been classified according to their respective source area types in Section 9.5, Table 9. The implementation for each will be prioritized according to the source area classifications and the information provided in Sections 9.5.1 and 9.5.2, with examples provided in Sections E.1 and E.2, below. For all impaired waterbodies, the determination of source area types serves to identify the predominant sources contributing to impairment (i.e., those that should be targeted initially for implementation). It is not intended to imply that sources in other landuse areas are not contributors to impairment and/or to grant an exemption from addressing other source area contributions with implementation strategies and corresponding load reduction. For mixed use areas, implementation will address both urban and agricultural areas, at a minimum.
E.1 Urban Source Areas
For impaired waterbodies and corresponding HUC-12 subwatersheds or drainage areas identified as predominantly urban source area types, Scarboro Creek provides an example for implementation analysis. Scarboro Creek was selected because of its high proportion (41.9 percent) of urban area. The Scarboro Creek subwatershed, in HUC-12 060102070403, lies within the boundaries of Oak Ridge. The drainage area for Scarboro Creek is approximately 977 acres (1.53 mi2); therefore, four flow zones were used for the duration curve analysis (see Sect. 9.1.1).
The flow duration curve for Scarboro Creek at mile 0.1 was constructed using simulated daily mean flow for the period from 1/1/97 through 12/31/14 (mile 0.1 corresponds to the location of DOE monitoring station 8). This flow duration curve is shown in Figure E-1 and represents the cumulative distribution of daily discharges arranged to show percentage of time specific flows were exceeded during the period of record. Flow duration curves for other impaired waterbodies were developed using a similar procedure (Appendix C).
The E. coli LDC for Scarboro Creek (Figure E-2) was analyzed to determine the frequency with which observed daily water quality loads exceed the E. coli target maximum daily loading (941 CFU/100 mL x flow [cfs] x conversion factor) under four flow conditions (low, mid-range, moist, and high). Observation of the plot illustrates that exceedances occurred during moist conditions (Table E-3, Section E.4), indicating that the Scarboro Creek subwatershed may be impacted by non-point sources, dominant during high flow/runoff conditions.
Results indicate the implementation strategy for the Scarboro Creek subwatershed will require BMPs targeting non-point sources. Table E-1 presents an allocation table of LDC analysis statistics for Scarboro Creek E. coli and implementation strategies for each source category covering the entire range of flow (Stiles, 2003). The implementation strategies listed in Table E-1 are a subset of the categories of BMPs and implementation strategies available for application to the Lower Clinch River Watershed for reduction of E. coli loading and mitigation of water quality impairment from urban sources. Targeted implementation strategies and LDC analysis statistics for other impaired waterbodies and corresponding HUC-12 subwatersheds and drainage areas identified as predominantly urban source area types can be derived from the information and results available in Tables 12 and E-33.
LDCs for other impaired waterbodies were developed using a similar procedure (Appendix C) and are shown in Figures E-5 through E-20. The LDCs shown in Figures E-5 through E-20 (and the associated Tables E-4 through E-32) are based on the most recent sampling period (2012-2016). For Ernie’s Creek and Scarboro Creek, the LDCs are based on the entire period of record because there is no monitoring data for the most recent sampling period. Table E-33 presents LDC analyses (TMDLs, WLAs, LAs, and MOS) and PLRGs for all flow zones for all E. coli impaired waterbodies in the Lower Clinch River Watershed.
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Figure E-1. Flow Duration Curve for Scarboro Creek at RM 0.1
2.30E+10 x qm 2.30E+10 x qm 2.30E+10 x qm 2.30E+10 x qm
WLAs (MS4s) (CFU/day/acre)3 (1.856E+08)
-(2.35+7xqd)
(4.780E+07)
-(2.35+7xqd)
(1.820E+07)
-(2.35E+7xqd)
(5.466E+06)
-(2.35E+7xqd)
LA (CFU/day/acre)3 (1.856E+08)
-(2.35+7xqd)
(4.780E+07)
-(2.35+7xqd)
(1.820E+07)
-(2.35E+7xqd)
(5.466E+06)
-(2.35E+7xqd)
Implementation Strategies4
Municipal NPDES L M H
Stormwater Management H H
SSO Mitigation H M L
Collection System Repair H M
Septic System Repair L M M
Potential for source area contribution under given flow condition (H: High; M: Medium; L: Low)
qm = Mean Daily WWTP Discharge (cfs) qd = Facility (WWTP) Design Flow (cfs) * The Moist Conditions Flow zone represents the critical condition for E. coli loading in the Scarboro Creek subwatershed. 1 Tennessee Maximum daily water quality criterion for E. coli. 2 Reductions (percent) based on mean of observed percent load reductions in range. 3 LAs and MS4s are expressed as daily load per unit area in order to provide for future changes in the distribution of LAs and MS4s
(WLAs). 4 Example Best Management Practices for Urban Source reduction. Actual BMPs applied may vary and should not be limited according
to this grouping.
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E.2 Agricultural Source Areas For impaired waterbodies and corresponding HUC-12 subwatersheds or drainage areas identified as predominantly agricultural source area types, Hinds Creek provides an example for implementation analysis.
The Hinds Creek drainage area, part of HUC-12 060102070402, lies in a partially-urbanized area of Anderson county. The drainage area for Hinds Creek is approximately 42,074 acres (66 mi2); therefore, five flow zones were used for the duration curve analysis (see Sect. 9.1.1). The landuse for Hinds Creek is approximately 26% agricultural, with the remainder split between forest (61%) and urban (14%). Though Hinds Creek is categorized as Mixed Source Area Type (Table 11), the predominant landuse type and sources are agricultural (Table 3).
The flow duration curve for Hinds Creek at mile 0.7 was constructed using simulated daily mean flow for the period from 1/1/02 through 12/31/13 (mile 0.7 corresponds to the location of monitoring station HINDS000.7AN). This flow duration curve is shown in Figure E-3 and represents the cumulative distribution of daily discharges arranged to show percentage of time specific flows were exceeded during the period of record. Flow duration curves for other impaired waterbodies were developed using a similar procedure (see Appendix C).
The E. coli LDC for Hinds Creek (Figure E-4) was analyzed to determine the frequency with which observed daily water quality loads exceed the E. coli target maximum daily loading (941 CFU/100 mL x flow [cfs] x conversion factor) under four flow conditions (low, mid-range, moist, and high). Observation of the plot illustrates that exceedances over the entire period of record occurred in multiple flow regimes, with the highest exceedances occurring during dry conditions (see Table E-3, Section E.4). Because exceedances primarily occurring in the high end of dry conditions and low end of mid-range flows, the Hinds Creek drainage area is most likely impacted by a combination of point and non-point sources.
Results indicate the implementation strategy for the Hinds Creek drainage area will require BMPs targeting point and non-point sources. Table E-2 presents an allocation table of LDC analysis statistics for Hinds Creek E. coli and targeted implementation strategies for each source category covering the entire range of flow (Stiles, 2003). The implementation strategies listed in Table E-2 are a subset of the categories of BMPs and implementation strategies available for application to the Lower Clinch River Watershed for reduction of E. coli loading and mitigation of water quality impairment from agricultural sources. Targeted implementation strategies and LDC analysis statistics for other impaired waterbodies and corresponding HUC-12 subwatersheds and drainage areas identified as predominantly agricultural source area types can be derived from the information and results available in Tables 13 and E-33.
LDCs for other impaired waterbodies were developed using a similar procedure (Appendix C) and are shown in Figures E-5 through E-20. The LDCs shown in Figures E-5 through E-20 (and the associated Tables E-4 through E-32) are based on the most recent sampling period (2012-2016). For Ernie’s Creek and Scarboro Creek, the LDCs are based on the entire period of record because there is no monitoring data for the most recent sampling period. Table E-33 presents LDC analyses (TMDLs, WLAs, LAs, and MOS) and PLRGs for all flow zones for all E. coli impaired waterbodies in the Lower Clinch River Watershed.
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Figure E-3. Flow Duration Curve for Hinds Creek at RM 0.7
2.30E+10 x qm 2.30E+10 x qm 2.30E+10 x qm 2.30E+10 x qm 2.30E+10 x qm
WLAs (MS4s) (CFU/day/acre)3 (1.243E+08)
-(5.63E+5xqd)
(4.145E+07)
-(5.63E+5xqd)
(1.976E+07)
-(5.63E+5xqd)
(9.222E+06)
-(5.63E+5xqd)
(2.869E+06)
-(5.63E+5xqd)
LA (CFU/day/acre)3 (1.243E+08)
-(5.63E+5xqd)
(4.145E+07)
-(5.63E+5xqd)
(1.976E+07)
-(5.63E+5xqd)
(9.222E+06)
-(5.63E+5xqd)
(2.869E+06)
-(5.63E+5xqd)
Implementation Strategies4
Pasture and Hayland Management H H M L L
Livestock Exclusion M H H
Fencing M H H
Manure Management H H M L L
Riparian Buffers L M H M M
Potential for source area contribution under given flow condition (H: High; M: Medium; L: Low)
qm = Mean Daily WWTP Discharge (cfs) qd = Facility (WWTP) Design Flow (cfs) * The Dry Conditions-range flow zone represents the critical conditions for E. coli loading in the Hinds Creek drainage area. 1 Tennessee Maximum daily water quality criterion for E. coli. 2 Reductions (percent) based on mean of observed percent load reductions in range. 3 LAs and MS4s are expressed as daily load per unit area in order to provide for future changes in the distribution of LAs and MS4s (WLAs). 4 Example Best Management Practices for Agricultural Source reduction. Actual BMPs applied may vary and should not be limited according to this grouping.
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E.3 Forestry Source Areas
There are no impaired waterbodies with corresponding HUC-12 subwatersheds or drainage areas classified as source area type predominantly forested, with the predominant source category being wildlife, in the Lower Clinch River Watershed.
E.4 Calculation of Percent Load Reduction Goals and Determination of Critical Flow
Zones
In order to facilitate implementation, corresponding percent reductions in loading required to decrease existing, in-stream E. coli loads to TMDL target levels (percent load reduction goals) were calculated. As a result, critical flow zones were determined and subsequently verified by secondary analyses. The following example is from Coal Creek at mile 1.2 (Figure C-2) and includes data for the past two monitoring cycles. 1. For each flow zone, the mean of the percent exceedances of individual loads relative to their
respective target maximum loads (at their respective PDFEs) was calculated. Individual loads with no required load reduction are not included in the mean calculation. The following illustrates the calculation of the PLRG for the mid-range flow zone:
2. The PLRGs calculated for each of the flow zones, not including the high flow zone (see Section
9.1.1), were compared and the PLRG of the greatest magnitude indicates the critical flow zone for prioritizing implementation actions for Coal Creek at mile 1.2.
Example – High Flow Zone Percent Load Reduction Goal = NR
Moist Conditions Flow Zone Percent Load Reduction Goal = 52.6 Mid-Range Flow Zone Percent Load Reduction Goal = 42.3 Low Flow Zone Percent Load Reduction Goal = 4.0
Therefore, the critical flow zone for prioritization of Coal Creek implementation activities is the Moist Conditions Zone and subsequently actions targeting non-point source controls.
3. Due to the frequently limited availability of sampling data and subsequent randomness of distribution of samples by flow zone, the determination of the critical flow zone by PLRG calculation often has a high degree of uncertainty. Therefore, secondary analyses were conducted to verify or supplement the determination of the critical flow zones. For each flow
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zone, the percent of samples that exceed the E. coli TMDL target levels was calculated. For Coal Creek at mile 1.2:
Flow Zone Number of
Samples
Samples > 941
CFU/100 mL
% > 941
CFU/100 mL
High 1 0 0
Moist 6 1 16.7
Mid-Range 10 3 30.0
Low 6 1 16.7
Based on the number of exceedances in each flow zone, the critical flow zone for prioritization of Coal Creek implementation activities is identified as the Mid-Range Flow zone. Whenever the two methods of determining critical flow zone produce different results, both flow zones should be targeted for implementation activities.
4. Lastly, emphasis (priority) should be placed on recent data versus historical data. If data from
multiple watershed cycles are available, analysis of recent data (current cycle) versus the entire period of record, or previous cycles, may identify different critical areas for implementation
Zone Past 2 Cycles (2008-13) Most Recent Cycle (2012-13)
# of samples % Red. % Exceed. # of samples % Red. % Exceed.
High 1 NR 0 0 NA 0.0
Moist 6 52.6 16.7 1 NR 0.0
Mid-Range 10 42.3 30.0 2 52.6 50.0
Low 6 4.0 16.7 2 4.0 50.0
The critical flow zone for prioritization of implementation activities for Coal Creek was identified as the Mid-Range Flow zone. Whenever a different flow zone, or zones, is identified, the flow zone(s) from analysis of recent data would have emphasis for implementation prioritization.
PLRGs and critical flow zones of the other impaired waterbodies were derived in a similar manner and are shown in Table E-33.
Geometric Mean Data
For cases where five or more samples were collected over a period of not more than 30 consecutive days, the geometric mean E. coli concentration was determined and compared to the target geometric mean E. coli concentration of 126 CFU/100 mL. If the sample geometric mean exceeded the target geometric mean concentration, the reduction required to reduce the sample geometric mean value to the target geometric mean concentration was calculated.
Example: Monitoring Location = Coal Creek Mile 1.2 Sampling Period = 7/30/13 – 8/26/13 Geometric Mean Concentration = 794.6 CFU/100 mL Target Concentration = 126 CFU/100 mL Reduction to Target = 84.1%
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For impaired waterbodies where monitoring data are limited to geometric mean data only, results can be utilized for general indication of relative impairment and, when plotted on a load duration curve, may indicate areas for prioritization of implementation efforts. For impaired waterbodies where both types of data are available, geometric mean data may be utilized to supplement the results of the individual flow zone calculations.
Table E-3. Summary of Critical Conditions for Impaired Waterbodies in the
Lower Clinch River Watershed
Waterbody ID HUC-12 Moist Mid-
Range Dry Low Monitoring Station
Drainage Area (ac)
Bullrun Creek (_3000) b
0101 BULLR031.2UN 11,437
N Fork Bullrun Creek
Bullrun Creek (_1000) 0102 BULLR016.2KN 42,840
Bullrun Creek (_2000) b
Beaver Creek (_3000) b
0201 BEAVE040.1KN 5,673 Hines Branch
Knob Fork
Willow Fork
Beaver Creek (_1000) a
0202 BEAVE024.7KN 35,251
Beaver Creek (_2000) a
Grassy Creek
Meadow Creek
Plumb Creek
EFork Poplar Creek (_1000)
a
0302 EFPOP006.9RO 8,534 EFork Poplar Creek
(_2000)
Coal Creek (_1000) b
0401 COAL001.2AN 23,016
Coal Creek (_2000)
Hinds Creek (_1000)
0402 HINDS000.7AN 40,891
Hinds Creek (_2000)
Hinds Creek (_3000)
Buffalo Creek
Byrams Creek
Ernie’s Creek 0403 Station 23 1,629
Scarboro Creek 0404 Station 8 977 a No critical condition. No exceedances of single sample maximum criterion during most recent sampling period, or the only exceedances were in the High Flow zone. b Critical condition based on geomean data and may not be a reliable indication of prioritization.
E. coli TMDL Lower Clinch River Watershed (HUC 06010207)
8/15/13 145 23.2% 111 142.7 11.7 20.8 Note: Geometric Mean is calculated whenever 5 or more samples are collected over a period of not more than 30 consecutive days.
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Table E-6. Calculated Load Reduction Based on Daily Loading – Beaver Creek – RM 24.7
Sample Date
Flow Regime
Flow PDFE Concentration Load % Reduction to Achieve TMDL *
Average of Load Reductions
% Reduction to TMDL – MOS
[cfs] [%] [CFU/100 ml] [CFU/day] [%] [%] [%]
8/13/13 Moist Conditions
125 14.8% 488 1.49E+12 NR
NR NR 8/15/13 78.8 26.1% 236 4.55E+11 NR
7/25/13 Mid-Range
Flows 33.4 55.7% 387 3.16E+11 NR NR NR
8/1/13 Dry Conditions
14.8 78.2% 921 3.34E+11 NR
NR NR 8/6/13 8.24 88.4% 299 6.03E+10 NR Note: NR = No reduction required
* % Reduction based on Single Sample Maximum Criterion (941 CFU/100 mL)
Table E-7. Calculated Load Reduction Based on Geomean Data – Beaver Creek – RM 24.7
8/15/13 78.8 26.1% 236 414.8 69.6 72.8 Note: Geometric Mean is calculated whenever 5 or more samples are collected over a period of not more than 30 consecutive days.
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Table E-8. Calculated Load Reduction Based on Daily Loading – Beaver Creek – RM 40.1
Sample Date
Flow Regime
Flow PDFE Concentration Load % Reduction to Achieve TMDL *
Average of Load Reductions
% Reduction to TMDL – MOS
[cfs] [%] [CFU/100 ml] [CFU/day] [%] [%] [%]
8/13/13 Moist Conditions
16.4 16.4% 1300 5.22E+11 27.6
44.4 49.9 8/15/13 11.4 27.3% 2420 6.72E+11 61.1
7/25/13 Mid-Range Flows
4.40 59.8% 548 5.89E+10 NR
33.5 40.1 8/1/13 3.39 68.4% 1414 1.17E+11 33.5
8/6/13 Low Flows 1.41 87.5% 613 2.11E+10 NR NR NR Note: NR = No reduction required
* % Reduction based on Single Sample Maximum Criterion (941 CFU/100 mL)
Table E-9. Calculated Load Reduction Based on Geomean Data – Beaver Creek – RM 40.1
8/15/13 11.4 27.3% 2420 1084 88.4 89.6 Note: Geometric Mean is calculated whenever 5 or more samples are collected over a period of not more than 30 consecutive days.
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Table E-10. Calculated Load Reduction Based on Daily Loading – Bullrun Creek – RM 5.2
Sample Date
Flow Regime
Flow PDFE Concentration Load % Reduction to Achieve TMDL *
Average of Load Reductions
% Reduction to TMDL – MOS
[cfs] [%] [CFU/100 ml] [CFU/day] [%] [%] [%]
8/15/13 Moist
Conditions 163 17.5% 291 1.16E+12 NR NR NR
8/26/13 Mid-Range
Flows 69.4 44.1% 326 5.54E+11 NR NR NR
7/30/13 Dry
Conditions
29.6 72.0% 261 1.89E+11 NR
NR NR
8/8/13 26.0 75.8% 185 1.18E+11 NR
8/5/13 22.4 79.1% 155 8.49E+10 NR Note: NR = No reduction required
* % Reduction based on Single Sample Maximum Criterion (941 CFU/100 mL)
Table E-11. Calculated Load Reduction Based on Geomean Data – Bullrun Creek – RM 5.2
8/26/13 69.4 44.1% 326 234.6 46.3 51.8 Note: Geometric Mean is calculated whenever 5 or more samples are collected over a period of not more than 30 consecutive days.
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Table E-12. Calculated Load Reduction Based on Daily Loading – Bullrun Creek – RM 16.2
Sample Date
Flow Regime
Flow PDFE Concentration Load % Reduction to Achieve TMDL *
Average of Load Reductions
% Reduction to TMDL – MOS
[cfs] [%] [CFU/100 ml] [CFU/day] [%] [%] [%]
8/15/13 Moist
Conditions 115 17.3% 179 5.03E+11 NR NR NR
8/26/13 Mid-Range
Flows 49.50 44.3% 345 4.18E+11 NR NR NR
7/30/13 Dry
Conditions
20.93 72.6% 727 3.72E+11 NR
4.0 13.6
8/8/13 20.79 72.9% 980 4.99E+11 4.0
8/5/13 16.04 79.2% 260 1.02E+11 NR Note: NR = No reduction required
* % Reduction based on Single Sample Maximum Criterion (941 CFU/100 mL)
Table E-13. Calculated Load Reduction Based on Geomean Data – Bullrun Creek – RM 16.2
8/26/13 49.50 44.3% 345 409.0 69.2 72.4 Note: Geometric Mean is calculated whenever 5 or more samples are collected over a period of not more than 30 consecutive days.
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Table E-14. Calculated Load Reduction Based on Daily Loading – Bullrun Creek – RM 31.1
Sample Date
Flow Regime
Flow PDFE Concentration Load % Reduction to Achieve TMDL *
Average of Load Reductions
% Reduction to TMDL – MOS
[cfs] [%] [CFU/100 ml] [CFU/day] [%] [%] [%]
8/15/13 Moist
Conditions 29.3 17.5% 687 4.92E+11 NR NR NR
8/26/13 Mid-Range
Flows 12.9 44.0% 199 6.27E+10 NR NR NR
8/8/13
Low Flows
5.73 70.6% 2420 3.39E+11 61.1
61.1 65.0
7/30/13 5.39 72.5% 308 4.06E+10 NR
8/5/13 4.28 78.8% 488 5.11E+10 NR Note: NR = No reduction required
* % Reduction based on Single Sample Maximum Criterion (941 CFU/100 mL)
Table E-15. Calculated Load Reduction Based on Geomean Data – Bullrun Creek – RM 31.1
8/26/13 12.9 44.0% 199 548.7 77.0 79.4 Note: Geometric Mean is calculated whenever 5 or more samples are collected over a period of not more than 30 consecutive days.
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Table E-16. Calculated Load Reduction Based on Daily Loading – Byrams Creek – RM 0.4
Sample Date
Flow Regime
Flow PDFE Concentration Load % Reduction to Achieve TMDL *
Average of Load Reductions
% Reduction to TMDL – MOS
[cfs] [%] [CFU/100 ml] [CFU/day] [%] [%] [%]
8/15/13 Moist
Conditions 17.7 15.7% 613 2.66E+11 NR NR NR
8/26/13 Mid-Range Flows
6.79 45.3% 579 9.62E+10 NR
NR NR 8/8/13 3.56 67.4% 435 3.79E+10 NR
7/30/13 Low Flows
3.26 70.1% 378 3.02E+10 NR
NR NR 8/5/13 2.72 75.5% 613 4.08E+10 NR Note: NR = No reduction required
* % Reduction based on Single Sample Maximum Criterion (941 CFU/100 mL)
Table E-17. Calculated Load Reduction Based on Geomean Data – Byrams Creek – RM 0.4
8/26/13 6.79 45.3% 579 513.7 75.5 78.0 Note: Geometric Mean is calculated whenever 5 or more samples are collected over a period of not more than 30 consecutive days.
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Table E-18. Calculated Load Reduction Based on Daily Loading – Coal Creek – RM 1.2
Sample Date
Flow Regime
Flow PDFE Concentration Load % Reduction to Achieve TMDL *
Average of Load Reductions
% Reduction to TMDL – MOS
[cfs] [%] [CFU/100 ml] [CFU/day] [%] [%] [%]
8/15/13 Moist
Conditions 60.3 19.0% 649 9.58E+11 NR NR NR
8/26/13 Mid-Range Flows
24.4 49.3% 365 2.18E+11 NR
52.6 57.4 8/8/13 19.9 56.4% 1986 9.68E+11 52.6
7/30/13 Low Flows
12.7 72.8% 687 2.13E+11 NR
4.0 13.6 8/5/13 10.9 77.5% 980 2.62E+11 4.0 Note: NR = No reduction required
* % Reduction based on Single Sample Maximum Criterion (941 CFU/100 mL)
Table E-19. Calculated Load Reduction Based on Geomean Data – Coal Creek – RM 1.2
8/26/13 24.4 49.3% 365 794.6 84.1 85.8 Note: Geometric Mean is calculated whenever 5 or more samples are collected over a period of not more than 30 consecutive days.
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Table E-20. Calculated Load Reduction Based on Daily Loading – Coal Creek – RM 10.6
Sample Date
Flow Regime
Flow PDFE Concentration Load % Reduction to Achieve TMDL *
Average of Load Reductions
% Reduction to TMDL – MOS
[cfs] [%] [CFU/100 ml] [CFU/day] [%] [%] [%]
8/15/13 Moist
Conditions 15.8 18.7% 93 3.59E+10 NR NR NR
8/26/13 Mid-Range Flows
6.54 47.5% 141 2.26E+10 NR
NR NR 8/8/13 3.47 68.5% 228 1.93E+10 NR
7/30/13 Low Flows
3.21 71.4% 30 2.35E+09 NR
NR NR 8/5/13 2.74 76.2% 194 1.30E+10 NR Note: NR = No reduction required
* % Reduction based on Single Sample Maximum Criterion (941 CFU/100 mL)
Table E-21. Calculated Load Reduction Based on Geomean Data – Coal Creek – RM 10.6
8/26/13 6.54 47.5% 141 111.7 NR NR Note: Geometric Mean is calculated whenever 5 or more samples are collected over a period of not more than 30 consecutive days.
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Table E-22. Calculated Load Reduction Based on Daily Loading – E. Fork Poplar Creek – RM 6.9
Sample Date
Flow Regime
Flow PDFE Concentration Load % Reduction to Achieve TMDL *
Average of Load Reductions
% Reduction to TMDL – MOS
[cfs] [%] [CFU/100 ml] [CFU/day] [%] [%] [%]
8/13/13 High Flows 72.3 6.9% 365 6.46E+11 NR NR NR
8/15/13 Moist
Conditions 26.6 26.9% 345 2.24E+11 NR NR NR
8/1/13 Mid-Range Flows
19.0 45.3% 488 2.27E+11 NR
NR NR 7/25/13 16.6 54.1% 108 4.39E+10 NR
8/6/13 Low Flows 11.5 83.7% 138 3.88E+10 NR NR NR Note: NR = No reduction required
* % Reduction based on Single Sample Maximum Criterion (941 CFU/100 mL)
Table E-23. Calculated Load Reduction Based on Geomean Data – E. Fork Poplar Creek – RM 6.9
8/15/13 26.6 26.9% 345 246.8 48.9 54.2 Note: Geometric Mean is calculated whenever 5 or more samples are collected over a period of not more than 30 consecutive days.
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E-29
Table E-24. Calculated Load Reduction Based on Daily Loading – Ernie’s Creek – RM 0.1
Sample Date
Flow Regime
Flow PDFE Concentration Load % Reduction to Achieve TMDL *
Average of Load Reductions
% Reduction to TMDL – MOS
[cfs] [%] [CFU/100 ml] [CFU/day] [%] [%] [%]
5/1/07 Mid-Range
Flows 1.18 57.9% 328 9.47E+09 NR NR NR
11/8/99
Low Flows
0.523 78.8% 219 2.80E+09 NR
61.1 65.0
10/9/00 0.469 81.0% 75 8.61E+08 NR
6/19/00 0.340 86.2% 2419 2.01E+10 61.1
10/15/08 0.230 91.6% 248 1.39E+09 NR
9/24/07 0.193 93.7% 2419 1.14E+10 61.1
5/7/01 0.128 96.7% 2419 7.58E+09 61.1
6/26/08 0.108 97.8% 249 6.57E+08 NR
6/22/99 0.087 98.7% 76 1.63E+08 NR Note: NR = No reduction required
* % Reduction based on Single Sample Maximum Criterion (941 CFU/100 mL)
Table E-25. Calculated Load Reduction Based on Daily Loading – Hinds Creek – RM 0.7
Sample Date
Flow Regime
Flow PDFE Concentration Load % Reduction to Achieve TMDL *
Average of Load Reductions
% Reduction to TMDL – MOS
[cfs] [%] [CFU/100 ml] [CFU/day] [%] [%] [%]
8/15/13 Moist
Conditions 114 15.8% 411 1.15E+12 NR NR NR
8/26/13 Mid-Range
Flows 42.5 46.7% 687 7.15E+11 NR NR NR
8/8/13 Dry
Conditions
26.4 63.5% 461 2.98E+11 NR
NR NR
7/30/13 20.8 71.0% 613 3.11E+11 NR
8/5/13 17.6 76.1% 517 2.22E+11 NR Note: NR = No reduction required
* % Reduction based on Single Sample Maximum Criterion (941 CFU/100 mL)
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E-30
Table E-26. Calculated Load Reduction Based on Geomean Data – Hinds Creek – RM 0.7
8/26/13 42.5 46.7% 687 528.6 76.2 78.6 Note: Geometric Mean is calculated whenever 5 or more samples are collected over a period of not more than 30 consecutive days.
Table E-27. Calculated Load Reduction Based on Daily Loading – Hinds Creek – RM 6.8
Sample Date
Flow Regime
Flow PDFE Concentration Load % Reduction to Achieve TMDL *
Average of Load Reductions
% Reduction to TMDL – MOS
[cfs] [%] [CFU/100 ml] [CFU/day] [%] [%] [%]
8/15/13 Moist
Conditions 69.5 15.7% 517 8.79E+11 NR NR NR
8/26/13 Mid-Range Flows
26.1 45.8% 548 3.50E+11 NR
NR NR 8/8/13 13.3 68.7% 313 1.02E+11 NR
8/5/13 Low Flows 10.6 75.4% 387 1.00E+11 NR NR NR Note: NR = No reduction required
* % Reduction based on Single Sample Maximum Criterion (941 CFU/100 mL)
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E-31
Table E-28. Calculated Load Reduction Based on Daily Loading – Hinds Creek – RM 14.1
Sample Date
Flow Regime
Flow PDFE Concentration Load % Reduction to Achieve TMDL *
Average of Load Reductions
% Reduction to TMDL – MOS
[cfs] [%] [CFU/100 ml] [CFU/day] [%] [%] [%]
8/15/13 Moist
Conditions 28.4 15.8% 238 1.65E+11 NR NR NR
8/26/13 Mid-Range Flows
10.7 46.0% 687 1.80E+11 NR
NR NR 8/8/13 5.82 66.3% 488 6.95E+10 NR
7/30/13 Low Flows
5.09 70.5% 517 6.44E+10 NR
NR NR 8/5/13 4.31 75.4% 461 4.86E+10 NR Note: NR = No reduction required
* % Reduction based on Single Sample Maximum Criterion (941 CFU/100 mL)
Table E-29. Calculated Load Reduction Based on Geomean Data – Hinds Creek – RM 14.1
8/26/13 10.7 46.0% 687 452.7 72.2 75.0 Note: Geometric Mean is calculated whenever 5 or more samples are collected over a period of not more than 30 consecutive days.
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Table E-30. Calculated Load Reduction Based on Daily Loading – Scarboro Creek – RM 0.1
Sample Date
Flow Regime
Flow PDFE Concentration Load % Reduction to Achieve TMDL *
Average of Load Reductions
% Reduction to TMDL – MOS
[cfs] [%] [CFU/100 ml] [CFU/day] [%] [%] [%]
10/8/98
Moist Conditions
3.41 15.5% 1414 1.18E+11 33.5
21.7 29.6
6/15/98 2.82 19.6% 411 2.83E+10 NR
6/2/08 2.30 24.6% 613 3.44E+10 NR
12/4/97 1.79 31.6% 135 5.90E+09 NR
10/7/02 1.53 36.2% 1046 3.91E+10 10.0
6/8/00 Mid-Range
Flows
1.04 49.2% 101 2.57E+09 NR
NR NR
4/24/07 1.00 50.5% 115 2.82E+09 NR
10/8/01 0.604 65.5% 649 9.58E+09 NR
11/8/99
Low Flows
0.374 78.2% 61 5.58E+08 NR
NR NR
10/10/00 0.314 81.7% 488 3.75E+09 NR
4/30/01 0.257 85.1% 157 9.86E+08 NR
9/20/07 0.208 88.4% 326 1.66E+09 NR
9/20/07 0.208 88.4% 261 1.33E+09 NR
10/16/08 0.156 92.4% 435 1.66E+09 NR
6/22/99 0.068 98.6% 12 2.01E+07 NR Note: NR = No reduction required
* % Reduction based on Single Sample Maximum Criterion (941 CFU/100 mL)
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Table E-31. Calculated Load Reduction Based on Daily Loading – Willow Fork – RM 0.5
Sample Date
Flow Regime
Flow PDFE Concentration Load % Reduction to Achieve TMDL *
Average of Load Reductions
% Reduction to TMDL – MOS
[cfs] [%] [CFU/100 ml] [CFU/day] [%] [%] [%]
8/13/13 Moist Conditions
11.6 18.9% 365 1.04E+11 NR
NR NR 8/15/13 9.20 26.5% 461 1.04E+11 NR
7/25/13 Mid-Range
Flows 3.47 59.9% 365 3.10E+10 NR NR NR
8/1/13 Low Flows
2.39 71.5% 260 1.52E+10 NR
NR NR 8/6/13 1.14 87.5% 308 8.59E+09 NR Note: NR = No reduction required
* % Reduction based on Single Sample Maximum Criterion (941 CFU/100 mL)
Table E-32. Calculated Load Reduction Based on Geomean Data – Willow Fork – RM 0.5
8/15/13 9.20 26.5% 461 345.4 63.5 67.3 Note: Geometric Mean is calculated whenever 5 or more samples are collected over a period of not more than 30 consecutive days.
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E-34
Table E-33. Summary of TMDLs, WLAs, & LAs by Flow Regime for Impaired Waterbodies in the Lower Clinch
Notes: NA = Not Applicable. NR = No Reduction Required. PLRG = Percent Load Reduction Goal to achieve TMDL. qm = Mean Daily WWTP Discharge (cfs) qd = Facility (WWTP) Design Flow (cfs) Shaded Flow Zone for each waterbody represents the critical flow zone.
a. Flow applied to TMDL, MOS, and allocation (WLA[MS4] and LA) calculations. Flows represent the midpoint value in the respective hydrologic flow regime. b. PLRG based on geomean data. c. WLAs for WWTPs are expressed as E. coli loads (CFU/day). All current and future WWTPs must meet water quality standards as specified in their NPDES permit. d. WLAs and LAs expressed on a “per acre” basis are calculated based on the drainage area at the specific monitoring point (see Table E-3). As regulated MS4 area increases
(due to future growth and/or new MS4 designation), unregulated LA area decreases by an equivalent amount. The sum will continue to equal total subwatershed area. e. No WWTPs currently discharging into or upstream of the waterbody. (WLA[WWTPs] Expression is future growth term for new WWTPs.) f. No MS4s currently located in the subwatershed drainage area. (Expression is future growth term for expanding or newly designated MS4s.) g. No critical condition. No exceedances of single sample maximum criterion during most recent sampling period, or the only exceedances were in the High Flow zone.
E. coli TMDL Lower Clinch River Watershed (HUC 06010207)
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F-1
APPENDIX F
Trend Analysis for Waterbodies Impaired by E. coli
in the Lower Clinch River Watershed
E. coli TMDL Lower Clinch River Watershed (HUC 06010207)
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F-2
In the Lower Clinch River Watershed, periods of record greater than 5 years (given adequate sampling frequency) were evaluated for trend analysis. For watersheds in second or successive TMDL cycles, data collected from multiple cycles were compared. If implementation efforts have been initiated to reduce loading, evaluation of routine monitoring data may indicate improving or worsening conditions over time and corresponding effectiveness of implementation efforts.
Water quality data for implementation effectiveness analysis can be presented in multiple ways. Several examples are shown in Section 9.6. Load duration curve methodology is most appropriate when monthly monitoring data, representative of all flow regimes, have been collected. However, in the Lower Clinch River Watershed, most of the recent monitoring data have been collected for geomean analysis (5 or more samples in a 30-day period). Therefore, box and whisker plots have been selected as the most appropriate method of presenting the monitoring data. Data intended for geomean analysis are grouped together for each specific 30-day period and the maximum geomean within that 30-day period is represented by a red dot. Data covering a period greater than 30 days are grouped together by sampling cycle, a 12-month period usually not coincident with the calendar year. In this case, the mean of the data is represented by a white diamond.
All of the waterbodies in the Lower Clinch River Watershed listed as impaired by E. coli had sufficient monitoring data to perform trend analysis. At this time, most of the impaired waterbodies in the Lower Clinch River Watershed show no obvious trend. In some cases, the results have fluctuated; in other cases, the results have remained essentially the same. Part of the reason for the uncertainty is the predominance of geomean sampling over the past decade. Geometric mean sampling is useful when listing a waterbody. Geomean sampling can only be used to determine the condition of a given waterbody during a 30-day period and, by itself, is inadequate to determine an overall trend. As stated in section 9.4.1, “comprehensive water quality monitoring activities include sampling during all seasons and a broad range of flow and meteorological conditions.”
Based on analysis of data from 1999 through 2013, the condition of Beaver Creek appears to be fluctuating, with no overall trend apparent. Figures F-1 and F-2 show the results of monitoring for
segment TN06010207011_1000 at mile 3.5. Figures F-3 and F-4 show the results of monitoring for
segment TN06010207011_2000 at mile 24.7. Figures F-5 and F-6 show the results of monitoring
for segment TN06010207011_3000 at miles 40.1. Figure F-7 compares the results of monitoring at all three locations on the same dates in 2013. Figure F-7 suggests that the impairment is greater further upstream, possibly due to the effect of dilution downstream. Additional improvement will be required before Beaver Creek can re-attain water quality standards.
Based on analysis of data from 2003 through 2013, the condition of Buffalo Creek at miles 0.3 and
0.7 (TN06010207016_0100) shows no overall trend (Figures F-8 and F-9). Although there have been no exceedances of the single sample maximum criterion since 2008, the geomean values in 2008 (391 cfu/100 mL) and 2013 (345 cfu/100 mL) are still above the geomean criterion. Additional improvement will be required before Buffalo Creek can re-attain water quality standards.
Based on analysis of data from 1998 through 2013, the condition of Bullrun Creek appears to be fluctuating, with no overall trend apparent. Figure F-10 shows the results of monitoring for all three
segments. Figure 11 shows the results of monitoring for segment TN06010207014_1000). Figure
F-12 shows the results of monitoring for segment TN06010207014_2000. Figure F-13 compares the results of monitoring for all three segments on the same dates in 2013. Figure F-13 suggests the impairment is slightly greater further upstream, possibly due to the effect of dilution downstream. Additional improvement will be required before Bullrun Creek can re-attain water quality standards.
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F-3
Based on analysis of data from 2003 through 2013, the condition of Byrams Creek
(TN060102070167_0200) appears to indicate slight improvement (Figures F-14 and F-15). There were no exceedances of the single sample maximum criterion during the most recent sampling cycle, but the geomean values have remained essentially unchanged (403, 470, and 514 cfu/100 mL for 2008, 2010, and 2013 respectively). Additional improvement will be required before Byrams Creek can re-attain water quality standards.
Based on analysis of data from 1999 through 2013, the condition of Coal Creek appears to be fluctuating, with no overall trend apparent. Figure F-16 shows the results of monitoring for two monitoring sites on the two impaired segments. Figure-F-17 shows the results of monitoring for
segment TN06010207029_1000 at mile 1.2. Figure F-18 shows the results of monitoring for
segment TN06010207029_2000 at mile 10.6. Figure F-19 compares the results of monitoring for the two segments on the same dates in 2013. Figure F-19 suggests that the impairment is slightly greater closer to the mouth of the waterbody. Additional improvement will be required before Coal Creek can re-attain water quality standards.
Based on analysis of data from 2008 through 2013, the condition of East Fork Poplar Creek
(TN06010207026_1000 and TN06010207026_2000) shows no overall trend. Figure F-20 suggests that impairment is slightly greater at the downstream segment (at RM 6.9), but there was no monitoring at that location in 2013. Figure F-21 suggests that the condition of the upstream segment (at RM 8.6) is worsening. Additional improvement will be required before East Fork Poplar Creek can re-attain water quality standards.
Based on analysis of data from 1999 through 2008, the condition of Ernie’s Creek
(TN06010207006T_1100) appears to be unchanged. It is difficult to determine a trend with the limited number of samples. In Figure F-22, there appear to be high values, possibly associated with storm events, and low values, with no values in the mid-range. Additional improvement will be required before Ernie’s Creek can re-attain water quality standards.
Based on analysis of data from 2004 through 2013, the condition of Grassy Creek
(TN06010207011_0700) shows no overall trend. In Figure F-24, there were no exceedances of the single sample maximum criterion during the most recent sampling cycle. However, in Figure F-25, the geomean value still exceeds the geomean criterion. Additional improvement will be required before Grassy Creek can re-attain water quality standards.
Based on analysis of data from 1999 through 2013, the condition of Hinds Creek
(TN06010207016_1000, TN06010207016_2000, and TN06010207016_3000) suggests improvement. Figure F-26 illustrates that monitoring during 2003 through 2008 showed higher values than during 1999. However the magnitude of the exceedances decreased during 2010 and 2013. Figures F-27 through F-29 show the results of monitoring at stations on each of the three segments. Figure F-30 illustrates monitoring for all three segments during 2013. The values at monitoring locations on all three segments are in the same range. Additional improvement will be required before Hinds Creek can re-attain water quality standards.
Based on analysis of data from 2004 through 2013, the condition of Hines Creek
(TN06010207011_0500) appears to be improving. In Figure 31, there were no exceedances of the single sample maximum criterion during the most recent sampling cycle. However, in Figure F-32, the geomean values still exceed the geomean criterion. Additional improvement will be required before Hines Creek can re-attain water quality standards.
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Based on analysis of data from 2004 through 2013, the condition of Knob Creek
(TN06010207011_0600) appears to be improving. In Figure 33, there have been no exceedances of the single sample maximum criterion since 2006. However, in Figure F-34, the geomean values still exceed the geomean criterion. There were not enough samples in 2013 to calculate the geomean. Additional improvement will be required before Hines Creek can re-attain water quality standards.
Based on analysis of data from 2004 through 2013, the condition of Meadow Creek
(TN06010207011_0800) appears to be fluctuating, with no overall trend apparent. In Figures F-35 and F-36, there were no exceedances of the single sample maximum criterion in 2008 and the geomean value was below the geomean criterion. However, in 2013 there were exccedances of the single sample maximum criterion and the geomean criterion. It is possible that the decreased values in 2008 were due to the near-drought conditions. Additional improvement will be required before Meadow Creek can re-attain water quality standards.
Based on analysis of data from 2001 through 2013, the condition of North Fork Bullrun Creek
(TN06010207014_0400) shows no overall trend. In Figure F-37, there were no exceedances of the single sample maximum criterion during the most recent sampling cycle. However, in Figure F-38, the geomean value still exceeds the geomean criterion. Additional improvement will be required before North Fork Bullrun Creek can re-attain water quality standards.
Based on analysis of data from 2004 through 2013, the condition of Plumb Creek
(TN06010207011_0900) suggests slight improvement. In Figure F-39, there were no exceedances of the single sample maximum criterion since 2005. However, in Figure F-40, the geomean values still exceed the geomean criterion. Additional improvement will be required before Plumb Creek can re-attain water quality standards.
Based on analysis of data from 1997 through 2008, the condition of Scarboro Creek
(TN06010207006T_0900) suggests slight improvement. In Figure F-41, there were no exceedances of the single sample maximum criterion since 2005. However, in Figure F-42, the geomean values still exceed the geomean criterion. Additional improvement will be required before Scarboro Creek can re-attain water quality standards.
Based on analysis of data from 2004 through 2013, the condition of Willow Fork
(TN06010207011_0200) suggests slight improvement. In Figure F-43, there were no exceedances of the single sample maximum criterion since 2005. However, in Figure F-44, the geomean values still exceed the geomean criterion. Additional improvement will be required before Willow Fork can re-attain water quality standards.
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Figure F-43. Time Series Plot for Willow Fork – RM 0.5
10
100
1000
10000
2004-05 2008 2013
E. c
oli
Co
nce
ntr
atio
n (
cfu
/10
0 m
L)
Sampling Cycles
Willow Fork - Mile 0.5
Mean
GM
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Figure F-44. Box and Whisker Plot for Willow Fork – RM 0.5
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APPENDIX G
Public Notice Announcement
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STATE OF TENNESSEE
DEPARTMENT OF ENVIRONMENT AND CONSERVATION
DIVISION OF WATER RESOURCES
PUBLIC NOTICE OF AVAILABILITY OF PROPOSED TOTAL MAXIMUM DAILY LOAD (TMDL)
FOR E. COLI IN LOWER CLINCH RIVER WATERSHED (HUC 06010207), TENNESSEE Announcement is hereby given of the availability of Tennessee’s proposed Total Maximum Daily Load (TMDL) for E. coli in the Lower Clinch River watershed, located in eastern Tennessee. Section 303(d) of the Clean Water Act requires states to develop TMDLs for waters on their impaired waters list. TMDLs must determine the allowable pollutant load that the water can assimilate, allocate that load among the various point and nonpoint sources, include a margin of safety, and address seasonality.
A number of waterbodies in the Lower Clinch River watershed are listed on Tennessee’s Draft 2016 303(d) list as not supporting designated use classifications due, in part, to pasture grazing or discharges from MS4 areas. The TMDL utilizes Tennessee’s general water quality criteria, continuous flow data from a USGS discharge monitoring station located in proximity to the watershed, site specific water quality monitoring data, a calibrated hydrologic model, load duration curves, and an appropriate Margin of Safety (MOS) to establish allowable loadings of pathogens which will result in the reduced in-stream concentrations and attainment of water quality standards. The TMDL requires reductions of E. coli loading on the order of 11.7-88.4% in the listed waterbodies.
The Lower Clinch River E. coli TMDL may be downloaded from the Department of Environment and Conservation website:
http://www.tn.gov/environment/article/wr-ws-tennessees-total-maximum-daily-load-tmdl-program Technical questions regarding this TMDL should be directed to the following members of the Division of Water Resources staff:
Vicki S. Steed, P.E., Watershed Management Unit Telephone: 615-532-0707 David M. Duhl, Ph.D., Watershed Management Unit Telephone: 615-532-0438
Persons wishing to comment on the proposed TMDLs are invited to submit their comments in writing no later than July 25, 2017 to:
Department of Environment and Conservation Division of Water Resources
Watershed Management Section William R. Snodgrass Tennessee Tower
312 Rosa L. Parks Avenue, 11th Floor
Nashville, TN 37243 All comments received prior to that date will be considered when revising the TMDL for final submittal to the U.S. Environmental Protection Agency.
The TMDL and supporting information are on file at the Division of Water Resources, William R. Snodgrass Tennessee Tower, 312 Rosa L. Parks Avenue, 11th Floor, Nashville, Tennessee 37243. They may be inspected during normal office hours. Copies of the information on file are available on request.
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APPENDIX H
Public Comments Received
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APPENDIX I
Response to Public Comments
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The TMDL document identifies TDOT as a point source with the potential to contribute pathogens to the subject waterbodies. TDOT’s own data supports this conclusion. According to information presented to TDEC by TDOT in a presentation titled “Stormwater Runoff from Tennessee Highways” on September 8, 2015 “nutrients and pathogens appeared to be the only parameters to potentially be of concern”. All stormwater permittees, regardless of size, are considered potential sources and are assigned WLAs. TDEC acknowledges the work your agency does to minimize nonpoint source contributions, but TDEC recognizes TDOT as a potential source. TDEC supports prioritization of TDOT MS4 discharge locations to most efficiently allocate resources in order to remediate the most significant water quality issues. As long as TDOT meets the requirements of their MS4 permit and Storm Water Management Program, TDOT’s Storm Water Monitoring Plan will be considered to be consistent with the goals of this TMDL.