MEEE.. - DTIC · rad-i55 992 national proram for inspection of non-federal dams i/i baker pond dam vt 88i..(u) corps of engineers waltham mr new england div jun 80 unclassified f/g

RAD-i55 992 NATIONAL PRORAM FOR INSPECTION OF NON-FEDERAL DAMS i/iBAKER POND DAM VT 88i..(U) CORPS OF ENGINEERS WALTHAMMR NEW ENGLAND DIV JUN 80

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DTIC FORM 70A DOCUMENT PROCESSING SHEET PREVIOUS EDITION MAY BE USED UNTILDEC D M STOCK IS EXHAUSTED.DEC 83 " .- ,

RICHELIEU RIVER BASINp (N BROOKFIELD, VERMONT .0

- n BAKER POND DAMVT 00135

PHASE I INSPECTION REPORT q

NATIONAL DAM INSPECTION PROGRAM

DEPARTMENT OF THE ARMY

NEW ENGLAND DIVISION, CORPS OF ENGINEERSWALTHAM, MASS. 02154

JUNE, 1980

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rip ooni(T Al I 'UVp'4m lREPROODUCE AT GOVERNMENT FXVENSE

A

DISCLAIMER NOTICEj

THIS DOCUMENT IS BEST QUALITYPRACTICABLE. THE COPY FURNISHEDITO DTIC CONTAINED A SIGNIFICANT

NUMBER OF PAGES WHICH DO NOTREPRODUCE LEGIBLY.I

All,

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IINCI ASSITEDSECURITY CL ASSIFICATION OF THIS PAGE (When Date Inget*d)

REPORT DOCUMENTATION PAGE READ INSTRUCTIONSR DBEFORE COMPLETING FORM

I. REPORT NUMBER 2. GOVT ACCESSION NO. 3. RECIPIENT'S CATALOG NUMBER.--.. VT 00135

• TIT L E (and Subtitle) S. TYPE OF REPORT & PERIOD COVERED

Baker Pond Dam INSPECTION REPORT

NATIONAL PROGRAM FOR INSPECTION OF NON-FEDERAL 5. PERPORM.NGORO. REPORT HUumERDAMS _"

7. AUTHOR(a) 9. CONTRACT OR GRANT NUMIER(a)

U.S. ARMY CORPS OF ENGINEERSNEW ENGLAND DIVISION

.S I. PERFORMING ORGANIZATION NAME AND ADDRESS 10. PROGRAM WELEMENT, PROJECT. TASKV AREA & WORK UNIT NUMBERS

I, CONTROLLING OFFICE NAME AND ADDRESS I. REPORT DATE

DEPT. OF THE ARMY, CORPS OF ENGINEERS June 1980NEW ENGLAND DIVISION, NEDED 1-. NUMBEROF PAGES424 TRAPELO ROAD, WALTHAM, MA. 02254 4814- MONITORING AGENCY NAME A ADDRESS(It different from C mlolilina Office) It. SECURITY CLASS. (of Ohl@ report)

0

UNCLASSIFIEDISa. DECLASSIICATION/DOWNGRADING

SCHEDULE

IS. 0ISTRIBUTION STATEMENT (of thli Report)

APPROVAL FOR PUBLIC RELEASE: DISTRIBUTION UNLIMITED

17. DISTRIBUTION STATEMENT (o the aestract mnteved In Rilok 20. It dhleeal heam ReSPOr)

IW. SUPPLEMENTARY NOTES

Cover program reads: Phase I Inspection Report, National Dam Inspection Program;however, the official title of the program is: National Program for Inspection ofNon-Federal Dams; use cover date for date of report.

I9. KEY WORDS (Continue on ro.wers* old* ,, nec .m -id id"i"I 6Y iO, .k .mbet)

DAMS, INSPECTION, DAM SAFETY,Richelieu River Basin 1A

Brookfield, VT.Sunny Brook

20. ABSTRACT (Ceoi#nue on reverse aide It neceseay mi d i1de tlh by block Pi&Mb.r)

The dam is an earthfill embankment about 490 ft. long and 18 ft. high. The damis judged to be in poor condition. Structural components appear to be in good -condition. The dam is small in size woth a significant hazard potential.There are various recommendations and remedial measures which should be undertak nby the owner.

DD FOM 1473 EDITION OF 0 NOV 65 IS OBSOLETE

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BAKER POND DAMVT 00135

RICHELIEU RIVER BASINr BROOKFIELD, VERMONT

PHASE I INSPECTION REPORTNATIONAL DAM INSPECTION PROGRAM

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LETTE OF RANSITTA

FRO TH COP FENIER O HTT

FOMB UPDB THE CORPS OF ENGINEERS H TT

BRIEF ASSESSMENT

PHASE I INSPECTION REPORT

NATIONAL PROGRAM OF INSPECTION OF DAMS

Identification Number: VT 00135Name of Dam: BAKER POND DAMTown: BROOKFIELDCounty and State: ORANGE COUNTY, VERMONTStream: SUNNY BROOKDate of Inspection: MAY 5, 1980

The dam, constructed in 1956, is an earthfill embankment approximately490 feet long and 18 feet in height. The upstream slope is inclined at 3horizontal to 1 vertical; the downstream is inclined at 2 horizontal to 1 ver-tical and has no drainage blanket or toe drains. The outlet structure is areinforced concrete box 9 feet by 18 feet in plan by 11 feet deep. Theupstream end is fitted with stoplogs the full depth of the structure. Theoutlet pipe is a 48 inch reinforced concrete pipe. The earthen overflowspillway is approximately 60 feet long with a crest elevation about 0.2 feetabove the outlet structure top. A concrete core wall runs the full length of " -the spillway, no other slope protection is evident.

Based upon the visual inspection at the site, the dam is judged to be inpoor condition. This assessment is predicated upon the geotechnical aspectsas considerable seepage was noted from beneath the root mat downstream of thedam. The downstream dam face, spillway channel and outlet channel support aheavy growth of trees and bushes. Structural components (outlet structure andconduit) appear in good condition.

In accordance with Corps of Engineers Guidelines and the size (SMALL) andhazard (SIGNIFICANT) of the dam, the test flood selected for use in the analy-sis was equivalent to one-half the Probable Maximum Flood (PMF). Peak inflowto the pond is 1925 cfs; peak outflow is 1,500 cfs with the dam overtopped 0.1feet. The combined spillway and outlet structure capacity is 1,359 cubic feetper second (cfs), which is equivalent to 91% of the routed Test Flood outflow.

An engineering investigation should be performed to determine the origin

of, and necessary remedial measures for the seepage occurring at thedownstream toe of the dam; determine procedure for removal of trees growing onthe dam embankment and within 20 feet of the downstream toe, and proceduresand materials for backfilling after removal of root systems. The possiblenecessity for additional riprap on the upstream slope of the embankment and on 'Othe left training wall of the spillway should be investigated, along with the

* erodability of the earthen overflow spillway and the effect of overflows on thedownstream slope of the dam. A detailed hydraulic and hydrologic study shouldbe conducted to further assess the need for and means to increase the projectdischarge capacity. The owner should institute a program of annual technicalinspection, with repairs as necessary, and a formal program of operation andmaintenance fully documented to provide accurate records for futurereference. A formal downstream warning system should be developed to beimplemented in the event of flood flow or imminent dam failure.

Recommended investigation and remedial measures for correction of the toeseepage should proceed immediately upon the owner's receipt of this report.The remaining recommendations and any further remedial measures which arediscussed in Section 7 should be instituted within one year of the owner'sreceipt of this report.

Step en D. Murray,Project Manager 'A 2736

James W. Sewall ;mpanyPqAL

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This Phase I Inspection Report on Dam has beenreviewed by the undersigned Review Board members. In our opinion,the reported findings, conclusions, and recommendations are .0consistent with the Recommended Guidelines for Safety Inspection -of Dams, and with good engineering Judgment and practice, and ishereby submitted for approval.

CHARLES G. TIERSCH, Chairman:Chief, Foundation and Materials BranchEngineering Division

'K

FRED J. RAVENS, Jr., MemberChief, Design BranchEngineering Division

SAUL COOPER, MemberChief, Water Control BranchEngineering Division

APPROVAL RECOMMENDED:

JOE B. FRYAR

Chief, Engineering Division

THIS SHEET TO BE FURNISHED BY THE CORPS OF ENGINEERS 9

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PREFACE

This report is prepared under guidance contained in the RecommendedGuidelines for Safety Inspection of Dams, for Phase I Investigations. Copieso" these guidelines may be obtained from the Office of Chief of Engineers,Washington, D.C. 20314. The purpose of a Phase I Investigation is toidentify expeditiously those dams which may pose hazards to human life or Iproperty. The assessment of the general condition of the dam is based uponavailable data and visual inspections. Detailed investigation, and analysesinvolving topographic mapping, subsurface investigations, testing, and de-tailed computational evaluations are beyond the scope of a Phase I investi-gation; however, the investigation is intended to identify any need for suchstudies.

In reviewing this report, it should be realized that the reported con-dition of the dam is based on observations of field conditions at the timeof inspection along with data available to the inspection team. In caseswhere the reservoir was lowered or drained prior to inspection, such action,while improving the stability and safety of the dam, removes the normal load Ion the structure and may obscure certain conditions which might otherwise bedetectable if inspected under the normal operating environment of the struc-ture.

It is important to note that the condition of a dam depends on numerousand constantly changing internal and external conditions, and is evolutionaryin nature. It would be incorrect to assume that the present condition of thedam will continue to represent the condition of the dam at some point in thefuture. Only through continued care and inspection can there be any chancethat unsafe conditions be detected.

Phase I inspections are not intended to provide detailed hydrologic and P.hydraulic analyses. In accordance with the established Guidelines, the Spill- -way Test flood is based on the estimated "Probable Maximum Flood" for the re-gion (greatest reasonably possible storm runoff"), or fractions thereof. Be-cause of the magnitude and rarity of such a storm event, a finding that aspillway will not pass the test flood should not be interpreted as necessarilyposing a highly inadequate condition. The test flood provides a measure of .relative spillway capacity and serves as an aide in determining the need formore detailed hydrologic and hydraulic studies, considering the size of thedam, its general condition and the downstream damage potential.

The Phase I Investigation does not include an assessment of the need forfences, gates, no-trespassing signs, repairs to existing fences and railings Pand other items which may be needed to minimize trespass and provide greatersecurity for the facility and safety to the public. An evaluation of the pro-ject for compliance with OSHA rules and regulations is also excluded.

I

REPROOUCE AT GOVERNMENT FXENSE

TABLE OF CONTENTS

SECTION PAGE

Letter of Transmittal

Brief Assessment

Review Board Page

Preface i

Table of Contents ii-iV

Overview Photo v

Lccation Map vi

REPORT

1. PROJECT INFORMATION 1-1

1.1 General i-1

a. Authority ib. Purpose of Inspection Program I-i

1.2 Description of Project 1-1

a. Location 1-1b. Description of Dam and Appurtenances i-ic. Size Classification 1-2d. Hazard Classification 1-2e. Ownership 1-2f. Operator 1-2g. Purpose of Dam 1-2h. Design and Construction History 1-2i. Normal Operational Procedures 1-3

1.3 Pertinent Data 1-3

a. Drainage Area 1-3b. Discharge at Dam Site 1-3c. Elevation 1-4d. Reservoir 1-4e. Storage 1-4f. Reservoir Surface 1-5g. Dam 1-5h. Diversion and Regulating Tunnel 1-5i. Spillway 1-5J. Regulating Outlets 1-6

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Section Page

2. ENGINEERING DATA 2-1

2.1 Design 2-1

a. Available Data 2-1b. Design Features 2-1c. Design Data 2-1

2.2 Construction 2-1

a. Available Data 2-1b. Construction Considerations 2-1

2.3 Operation 2-1Ak

2.4 Evaluation 2-1

a. Availability 2-1b. Adequacy 2-1c. Validity 2-1 -0

3. VISUAL INSPECTION 3-1

3.1 Findings 3-1 - -

a. General 3-1b. Dam 3-1 .0c. Appurtenant Structures 3-1d. Reservoir Area 3-2e. Downstream Channel 3-2

3.2 Evaluation 3-2

4. OPERATIONAL AND MAINTENANCE PROCEDURES 4-1

4.1 Operational Procedures 4-1

a. General 4-1b. Warning System 4-1 0

4.2 Maintenance Procedures 4-1

a. General 4-1b. Operating Facilities 4-1

4.3 Evaluation 4-1

5. EVALUATION OF HYDRAULIC/HYDROLOGIC FEATURES 5-1

5.1 General 5-1

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SECTION 4: OPERATIONAL AND MAINTENANCE PROCEDURES

4.1 OPERATIONAL PROCEDURES

a. General - Pond level readings are not taken on a regular basis. Afull column of stoplogs is normally in place.

b. Warning System - No warning system is known to exist.

4.2 MAINTENANCE PROCEDURES.0

a. General - The dam receives no regular maintenance. Dam inspectionreports consistently comment on the necessity to cut brush and grass.

b. Operating Facilities - Except for replacement of the stoplogs asthey deteriorate, no maintenance of operating facilities is performed.Existing stoplogs appear in good condition.

4.3 EVALUATION

The operation and maintenance procedures at this dam are inadequate toensure that all problems encountered can be remedied within a reasonableperiod of time. The owner should establish a written operation and main-tenance procedure as well as a warning system to follow in the event of floodflow conditions or imminent dam failure.

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Water seeping from beneath the root mat downstream of the downstream toemay be the result cf seepage conditions which, if not controlled, could leadto failure of the dam.

The trees growing on the downstream slope and at the downstream toe ofthe dam could cause seepage or erosion problems. Uprooted oi decaying treescould provide pathways for seepage which could lead to internal erosion of theembankment.

The trees growing in the spillway channel could impair the functicning ofthe spillway during large flows. .

The left training wall of the spillway which is formed by the embankmentcould be eroded during periods of large spillway flows.

Structural components (outlet structure and conduit) appear in good con-dition.

3-3

The seepage from the downstream toe area collects at a low point belowthe toe and drains toward the outlet channel as shown in Photo 8. Thisseepage enters the outlet channel at a point about 20 feet downstream of thehead wall of the outlet pipe. The flow at this point is shown in Photo 9.

c. Appurtenant Structures .

Spillway

The spillway section is located at the right abutment. The floor of thespillway channel is unlined, but there is a concrete core wall the top ofwhich is partially exposed, buried beneath the surface of the spillway. The 6left training wall of the spillway is formed by the embankment, which is par-tially protected from spillway flows by rock riprap.

Outlet Structure

The outlet structure is a reinforced concrete box, 9 feet by 18 feet inplan, with stoplog guides extending the full depth of the upstream side. Thestructure is shown in Photo 10. Access for insertion or removal of stoplogs,the top of which appear on the extreme right-of Photo 10, is gained by walkingthe 15 inch wide wall of the outlet structure, for which no handrail, safetycage, or other accident prevention device is provided. The top of theconcrete on the right side of this structure is approximately an inch lowerthan the concrete on the left. This differential has reportedly existed sincedam construction and is not considered significant. Along the left side,three feet down from the top, water is leaking in at a construction joint.The discharge pipe is 48 inch reinforced concrete with a concrete headwall atits exit. The headwall is in good condition. The discharge pipe joints havea minor amount of offset with no sign of leakage as shown in Photo 11.

d. Reservoir Area

The reservoir banks are typically lined with grass and low bushes with awell-defined footpath, a result of fishing activity, along the top of slope.There are no indications of instability along the banks of the reservoir inthe vicinity of the dam.

e. Downstream Channel

The downstream spillway channel is shown in Photo 12. The channel ispoorly defined in the area immediately downstream from the dam. Trees aregrowing in the spillway channel as shown in Photo 12.

3.2 EVALUATION

The visual inspection indicates the dam to be in poor condition withrespect to the geotechnical aspects.

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SECTION 3: VISUAL INSPECTION

3.1 FINDINGS

a. General - The general condition of this dam is fair.

At the time of inspection on May 5, 1980 the water level in the reservoirwas about 1 inch above the top of the intake structure. The weather was cooland cloudy wth occasional light showers.

b. Dam - The dam is an earth embankment with an unlined spillway sectionat the right abutment. A rectangular drop inlet intake structure is located "on the upstream slope.

The dam has a 900 bend at a rock outcrop in the reservoir forming an L-shaped crest with the short portion of the L extending from the rock outcroptoward the left abutment. The outcrop is shown in Photo 1.

Upstream Slope

The upstream face is inclined at a slope of 3 horizontal to 1 vertical.Approximately 6 feet of the upstream slope was above water level at the timeof inspection. Photo 2 shows a typical section of the upstream slope. Theslope is not protected by riprap and numerous large brush stumps have beenleft in place. There are small trees growing on the upstream slope just abovethe water line as shown in Photo 1. A new growth of brush is beginning togrow on the upstream slope.

Cresti

The crest of the embankment has a thin grass cover which has been worn bytrespassing as shown in Photo 3 and 4. No evidence of cracking or misalign-ment was observed.

Downstream Slope

The downstream slope is inclined at 2 horizontal to 1 vertical. Densehigh brush and saplings cover much of the slope. There is a cluster of larger -.- -trees growing on the slope at the point where the embankment makes the900 bend toward the left abutment. A general view of the brush on the down-stream slope is shown in Photo 5.

Seepage was observed at the downstream toe of the dam. The entire area atthe toe between the outlet pipe and the 900 bend was wet and soggy. In somelocations water was emerging from beneath the root mat. Photo 6 shows onelocation of concentrated flow emerging from beneath the root mat. The exitpoint is located about 20 feet downstream of the toe and about 60 feet left ofthe outlet pipe. The emerging seepage water is slightly turbid and a mound ofsilt has been deposited where the velocity of this concentrated flow isreduced. This silt deposit is shown in Photo 7.

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SECTION 2: ENGINEERING DATA

2.1 DESIGN

a. Available Data The available data consists of original design Idrawings by Louis M. Laushey, P.E., design topography by Lee H. Lowell, and Smiscellaneous computations and inspection reports by the Vermont Department ofWater Resources.

b. Design Features - The drawings, computations and inspection reportsindicate the design features stated in Section 1. S

c. Design Data - Design data consists of information on the designdrawings by Louis M. Laushey and Lee H. Lowell as listed in "Existing Plans".

2.2 CONSTRUCTION

a. Available Data - Information as contained in any plans, drawings, or •specifications previously listed in "Design Data" or Appendix B.

b. Construction Considerations - The dam, as built, varies significantlyfrom the design in that the dam top is approximately 2 feet lower and theoverflow spillway approximately I foot lower than shown on the originaldrawings. The outlet conduit is also oriented at a slightly different angle Sthan indicated on the design drawings and the outlet structure was constructedin line with the outlet conduit rather than normal to the dam crest. Threereinforced concrete struts across the outlet structure were constructed levelwith the top of the structure rather than arched two feet above it. No riprapprotection is apparent on the dam or spillway. -

2.3 OPERATION

Pond level readings are not taken on any regular schedule. No formaloperation procedures are known to exist.

2.4 EVALUATION S

a. Availability - Existing data was provided by the State of VermontAgency of Environmental Conservation (the owner) who also made the operationsavailable for visual inspection.

b. Adequacy - Detailed hydrologic/hydraulic data were not available.Design data and field measurements were utilized in conjunction with NewEngland Division - Army Corps of Engineers "Preliminary Guidance for Estimat-ing Maximum Probable Discharges" to perform the computations of outflow capa-city.

The detailed engineering data required to perform an in-depth stability 5analysis of the dam was not available. The final assessment of the dam,therefore, must be based primarily on visual inspection, performance history,and spillway capacity computations.

c. Validity - A comparison of records, data, and visual observationsreveals no significant discrepancies, other than those noted above betweendesign and as-built dimensions.

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5. Upstream channel: N/A

6. Downstream channel: Earthen channel tostreambed -

7. General: N/A .0

j. Regulating Outlets

1. Invert: 1289

2. Size: 9 ft. wide x 18 ft. long .x 11 ft. deep with 48inch pipe outlet

3. Description: Reinforced concrete struc-ture with stoplog guidesfull depth upstream end,horizontal 48 inch pipeoutlet downstream end

4. Control Mechanism: Stoplogs

5. Other: N/A

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f. Reservoir Surface

1. Normal pool: 50± acres

2. Flood control pool: N/A

3. Spillway crest: 50± acres

4. Test flood pool: 50± acres. 5. Top of dam: 50± acres

g. Dam

1. Type: Homogeneous Earthfill

" 2. Length: 490 ± ft

3. Height: 18± ft

4. Top width: 11 ft

V 5. Side Slopes: 3H to IV Upstream2H to 1V Downstream

6. Zoning: N/A

7. Impervious Core: N/A

8. Cutoff: N/A" 9. Grout curtain: N/A

10. Other: N/Ah. Diversion and Regulating Tunnel N/A

i. Spillway

1. Type: Earthfill overflowprotected by con-

crete cutoff wall

2. Length of Weir: 60± ft.

3. Crest el.: 1300.2±

4. Gates: N/A

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8. Total project discharge attop of dam el. 1304.0: 1359 cfs

9. Total project discharge attest flood el. 1304.1: 1500 cfs

c. Elevation (Feet, NGVD)

1. Streambed at toe of dam: 1286 ±

2. Bottom of cutoff: N/A

3. Maximum tailwater: N/A

4. Recreation pool: 1300±

5. Full flood control pool: N/A I

6. Spillway crest (ungated): 1300.2±

7. Design surcharge (original design): N/A

8. Top of dam: 1304±

9. Test flood surcharge: 1304.1

d. Reservoir

1 1. Length of normal pool: 2400± ft

2. Length of flood control pool: N/A

3. Length of spillway crest pool: 2400 ± ft

4. Length of pool at top of dam: 2400 ± ft

5. Length of test flood pool: 2400 ± ft

e. Storage I1. Normal pool: 200 acre-ft

2. Flood control pool: N/A

3. Spillway crest pool: 200 acre-ft j4. Top of dam: 400 acre-ft P

5. Test flood pool: 400 acre-ft

1-4

Vf. Operator - Mr. John Claussen, District BiologistDepartment of Fish and GameAgency of Environmental ConservationState of VermontMontpelier, Vermont 05602(802) 828-3371 .

g. Purpose of Dam - Recreation.

h. Design and Construction History - The following information isbelieved to be accurate based upon plans and correspondence available and fromconversations with persons familiar with the history of the dam. The dam wasdesigned in 1955 by Louis M. Laushey for the Vermont Department of Fish andGame. It was constructed in 1956. Shortly after the reservoir was filled,there was a failure caused by piping along the outlet conduit. The reservoirwas drained and the failure repaired, reportedly by addition of anti-seepcollar or collars.fo

i. Normal Operational Procedures - All stoplogs are normally in placesuch that water overflows all four sides of the outlet structure at approxi--

mate elevation 1300. The operator checks periodically to assure that the -outlet structure is not blocked by debris.

[ 1.3 PERTINENT DATA S

a. Drainage Area - 1.79 square miles of moderately steep, essentiallyundeveloped terrain which is 50% open and 50% wooded.

b. Discharge at Damsite - Discharge is from over the outlet structureIand through the 48 inch outlet conduit. Elevations are referenced to NGVD

datum.

1. Outlet works (conduits):

One 48" reinforced concrete* pipe @ Invert el. 1289 248 cfs

2. Maximum known flood at damsite: N/A

3. Ungated spillway capacity attop of dam el. 1304: 1111 cfs

4. Ungated spillway capacity attest flood el. 1304.1: 1250 cfs

5. Gated spillway capacity atnormal pool el. 1300: N/A

6. Gated spillway capacity attest flood el. 1304.1: N/A

7. Total spillway capacity attest flood el. 1304.1: 1250 cfs

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The earthen spillway has a crest elevation of approximately 1300.2 and atotal length of approximately 60 feet. A reinforced concrete core wallapproximately 2 feet thick by 4 feet deep with a top elevation of 1299.9 runsalong the spillway center. -

The outlet structure consists of a reinforced concrete box 9 feet by 18 77feet in plan with the bottom at elevation 1289.0. Control is achieved by

* 4 foot long stoplogs at the upstream end of the box. The top of the box is* open which allows for flow over the other three sides when all stoplogs are

in place. The stoplog guides extend full depth of the box. The outlet pipeis 48 inch diameter reinforced concrete, installed level with its invertmatching the bottom of the box.

Elevations are referenced to NGVD datum.

No instrumentation exists at this dam.

c. Size Classification - SMALL - The dam impounds 400 acre-feet of waterwith the pond level at the top of the dam, which at elevation 1304 NGVD is 18feet above the original streambed. With storage of less than 1000 acre-feetand height less than 40 feet, the dam falls into the small category of bothcriteria and is thus classified small in size according to the RecommendedGuidelines.

d. Hazard Classification - SIGNIFICANT - If the dam were breached, thereis potential for considerable property damage and loss of a few lives. About250 feet downstream of the dam is a residential structure approximately tenfeet above the streambed. With a rapid rise in flood stage from 4 feet to12 feet, this home would be jeopardized upon failure of the dam. Furtherdownstream, little damage to homes or other major buildings would be expected,as all are 15 feet or more above the streambed, and our hydraulicscomputations indicate maximum post-failure stages in the order of 10 feet.

Agricultural flooding, damage to private, town and state road crossings,and destruction of minor outbuildings would occur, however, as the failurewave traveled down the steeply sloped watercourse of Sunny Brook to itsconfluence with Dog River.

e. Ownership - Department of Fish and GameAgency of Environmental ConservationState of VermontMontpelier, Vermont 05602 -(802) 828-3371

The dam was built by its present owner.

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PHASE I INSPECTION REPORT

BAKER POND

SECTION I - PROJECT INFORMATION

1.1 GENERAL

. a. Authority - Public Law 92-367, August 8, 1972, authorized theSecretary of the Army, through the Corps of Engineers, to initiate a National

- Program of Dam Inspection throughout the United States. The New EnglandDivision of the Corps of Engineers has been assigned the responsibility ofsupervising the inspection of dams within the New England Region. James W.Sewall Company has been retained by the New England Division to inspect and

. report on selected dams in the State of Vermont. Authorization and notice to- proceed were issued to James W. Sewall Company under a letter of April 1, 1980

from William E. Hodgson, Jr. Colonel, Corps of Engineers. Contract No. DACW33-80-0051 has been assigned by the Corps of Engineers for this work.

b. Purpose of Inspection Program - The purposes of the program are to:

1. Perform technical inspection and evaluation of non-federal dams toidentify conditions requiring correction in a timely manner by non-federal interests.

2. Encourage and prepare the States to quickly initiate effective daminspection programs for non-federal dams.

3. To update, verify and complete the National Inventory of Dams.

1.2 DESCRIPTION OF PROJECT

a. Location - The dam is located on the headwaters of Sunny Brook in arural area of the Town of Brookfield, County of Orange, State of Vermont. Thedam is shown on the Barre USGS Quadrangle Map having coordinates latitudeN 440 04.3' and longitude W 720 38.2'.

b. Description of Dam and Appurtenances - The dam, completed in 1956,consists of a homogeneous rolled earthfill embankment having a total length ofapproximately 490 feet, including an emergency earthen overflow spillwayapproximately 60 feet long on the right side of the dam, and outlet works atthe central portion of the dam.

The embankment has a top elevation of approximately 1304, is 18 feet inheight above the streambed and is 11 feet wide at the crest. The upstreamslope is inclined at 3 horizontal to 1 vertical. The downstream slope isinclined at 2 horizontal to 1 vertical and has no drainage blanket or toedrains.

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j-,~ , -:'.2i§1'f *~~>\ . ~ 1~ts1~t/,LOCATION MAP.~ 1 C(~>C' M ~1H ~' . UGS1/ VERMONT

T, U..G.S.QUADRANGLEv*-I; ' BARRE 1957I

~ ~ U I I (~\N'/J SCLEOF MILES i

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czoz

Section Page

5.2 Design Data 5-1

5.3 Experience Data 5-1

5.4 Test Flood Analysis 5-1

5.5 Dam Failure Analysis 5-1

6. EVALUATION OF STRUCTURAL STABILITY 6-1

6.1 Visual Observation 6-1

6.2 Design and Construction Data 6-1

6.3 Post-Construction Changes 6-1

6.4 Seismic Stability 6-1

7. ASSESSMENT, RECOMMENDATIONS AND REMEDIAL MEASURES 7-1

7.1 Dam Assessment 7-i

a. Condition 7-1b. Adequacy of Information 7-1c. Urgency 7-1

* 7.2 Recommendations 7-1

7.3 Remedial Measures 7-1

7.4 Alternatives 7-2

APPENDIX

APPENDIX A VISUAL CHECK LIST WITH COMMENTS A-i

APPENDIX B -ENGINEERING DATA B-i

APPENDIX C - DETAIL PHOTOGRAPHS C-1

APPENDIX D - HYDRAULICS/HYDROLOGIC COMPUTATIONS D-1

APPENDIX E - INFORMATION AS CONTAINED IN THE E-1NATIONAL INVENTORY OF DAMS

iv

SECTION 5: EVALUATIUN OF HYDRAULIC/HYDROLOGIC FEATURES

5.1 GENERAL

The project is basically a low surcharge storage-high spillage earthembankment, constructed to impound water for recreational use only. Thespillway and overflow structure will pass 91% of the routed test flood outflow

.* with the dam overtopped by 0.1 feet.

-" 5.2 DESIGN DATA

No design data are known to exist for the project.

5.3 EXPERIENCE DATA

Other than a failure shortly after construction of the project, which wasprobably unrelated to hydraulic or hydrologic conditions, no information onserious problem situations arising at the dam were found, and it does notappear the dam has been overtopped.

5.4 TEST FLOOD ANALYSIS

The "Recommended Guidelines for Safety Inspection of Dams" presents a testflood range for significant hazard small size dams of the 100 year frequencyto one-half the Probable Maximum Flood (PMF). Selection of the test flood tobe utilized in the analysis of a particular dam is dependent upon the proxi-mity of the dam to the upper or lower limits of its size category and upon theperceived risk of failure. Due primarily to the latter consideration, thetest flood selected is equivalent to one-half the Probable Maximum Flood. Thetributary wastershed consists of 1.79 square miles of moderately steep, essen-tially undeveloped terrain about 50% open and 50% wooded. Using the curve forrolling" watersheds contained in the "Preliminary Guidance for Estimating

Maximum Probable Discharge", dated March, 1978, peak inflow to Baker Pond is1925 cfs. Routed Test Food outflow, with the pool initially at normal level

* (el. 1300 NGVD) is 1500 cfs with the dam overtopped 0.1 feet. Based upon ourhydraulics computations, the combined capacity of the spillway and outletstructure is 1359 cfs, which is approximately 91% of the routed Test Floodoutflow at the top of the dam.

5.5 DAM FAILURE ANALYSIS

Utilizing the April, 1978, "Rule of Thumb Guidance for EstimatingDownstream Dam Failure Hydrographs", the peak failure outflow would be 15,500cfs with the pool initially at the top of the dam (1304 NGVD). A breach of

* the dam would result in a rise of 8 feet in the water level of the stream atthe initial impact area, which is 250 feet downstream from the dam. This 8foot rise in flood stage corresponds to an increase in flow of 14,141 cfs andan increase in the water level from a depth of 4 feet just before the breach,to a depth of 12 feet just after the breach. The rapid 8 foot increase in the

5-1

*' ... .*.. . i . . 1 1 . 1 i ••." " .i . -.'. " ' " -. i - .i- - - -

water level would flood a residence in the initial impact area to a height ofapproximately 2 feet above first floor level. Further downstream on SunnyBrook, hydraulics computations indicate the stages reached would be on theorder of 10 feet - insufficient to damage residential or other largebuildings, the lowest of which are some 15 feet above the brook bottom. Theflood wave would cause flooding of agricultural areas, damage to private, townand state (Route 12) road crossings, and destruction of minor outbuildings.Because of the potential for loss of a few lives in the initial impact areaand the considerable downstream damage which would ensue from a breach, BakerPond Dam is classified as a "Significant Hazard" dam.

BU

ke-

5-2

' I

". 5-2

,.,.,

SECTION 6: EVALUATION OF STRUCTURAL STABILITY

6.1 VISUAL OBSERVATION

The visual inspection indicates the following potential structural

problems:

a. The presence of seepage at the downstream toe of the embankment, ifnot controlled, could lead to failure of the dam.

b. Erosion of the embankment could occur during periods of high flowover the spillway.

c. Areas of erosion or seepage could be created by the uprooting ordecay of large trees now growing on the embankment.6.2 DESIGN AND CONSTRUCTION DATA

No original design and construction data are available for the dam.

6.3 POST-CONSTRUCTION CHANGES

Mr. Peter Barranco of the Vermont Department of Water resources statedthat during the first filling of the reservoir a piping failure occurred alongthe outlet conduit. About 20 feet of the embankment was washed away. Repairsincluded a concrete cutoff wall across the conduit. Detailed constructiondrawings were not available.

6.4 SEISMIC STABILITY

The dam is located in Seismic Zone 2, and in accordance with the recom-mended Phase I guidelines does not warrant seismic investigation.

p p

6-1

-I." h

SECTION 7: ASSESSMENT, RECOMMENDATIONS AND REMEDIAL MEASURES

7.1 DAM ASSESSMENT

a. Condition - Based on a visual inspection, the dam is judged to be inpoor condition. This assessment is predicated upon the geotechnical aspects; 9the outlet structure and discharge pipe are in good condition.

b. Adequacy of Information - Due to the lack of design and constructiondata for this dam, the assessment of safety is based solely on the visualinspection.

c. Urgency - The recommendations and remedial measures presented belowshould be implemented by the owner within one year after receipt of thisPhase I Inspection Report, with the exception that recommendation 7.2a shouldbe implemented immediately after receipt of this report.

7.2 RECOMMENDATIONS

The owner should engage a qualified registered engineer to undertakefurther investigations as follow:

a. Assess significance of the seepage occurring at the downstream toe ofthe dam and design remedial measures if needed.

b. Determine procedures for removal of trees growing on the dam embank-ment and within 20 feet of the downstream toe and to assist in the selectionof suitable fill materials for backfilling of the voids left in the embankmentafter removal of the tree root systems.

c. Examine the need to provide additional riprap protection on theupstream slope of the embankment and on the left training wall of thespillway.

d. Investigate the erodability of the earthen overflow spillway and[] effect of overflows on the downstream slope of the dam.

e. Perform a detailed hydraulic and hydrologic study to further assess- the need for and means to increase the project discharge capacity.

The owner should implement all recommendations by the engineer.

- 7.3 REMEDIAL MEASURES

a. Brush should be cleared from the slopes of the dam and from the areawithin 10 feet of the downstream toe.

b. Trees and brush growing in the spillway channel should be cut.

c. A safe means of operator access to the stoplog slots should beprovided.

7-1

I1-- --- *. . ... .~ • .. . .. . .. . . . , -. . . . >-

- -- --. -

d. A program of annual technical inspection, with repairs as necessaryshould be instituted by the owner.

e. A formal program of operation and maintenance procedures should beinstituted and fully documented to provide accurate records for future .0reference.

f. A formal downstream warning system to be implemented in the event offlood flow or imminent dam failure conditions should be developed by theowner.

7.4 ALTERNATIVES

This study has identified no practical alternative to the above recom-mendations.

7-I2

II

7-2

..-.- .. -. -' --.. . . -.-- '. --- -. .' .. .- .' '- -, '. . . .. .- " .-' -- .' : . .- -" " -, -. . .-: , -: '- ., .. .-

I-I

APPEND IX A

VISUAL CHECK LIST WITH COMMENTS

I p

,1 ,. VISUAL INSPECTION CHECKLISTPARTY ORGANI ZATION

PROJECT . ?r;K-r ,.i'.,ui;! Dc, DATE /Ivj) 4 /zF

TIME //"/'5"

WEATHER /-,, °

W.S. ELEV.. /3oo U.S. DN.S.

PARTY:

- .. m' ,' ... , .z /.-I .. 6.

.3 " ' b/ 1: .": ' m 7.

____ -4_ _ _ _ _ _ __ _ _ _ _ _ _

• - ____ , ,_ _ L 9._

!) ..... " . .. . o 0 .

PROJI1 C- FIAIURE INSPECTED BY REMARKS

6..

A I

3 - . Z., , /7 c,'~f.. ' .. / ,.,.t- , C':-/

5. '_ , , - _ _ _ ____. _ __,--___ _" __•_ _, ____, __t_ __ __,__..'___Eu

I, ,*

6, 6

A-I-

PROJECT 0 ?.-, -. . . .'., DATE 5A v ..

• " PROJECT FEATURE DNH, ; ,-, .. , INE .

~DISCIPLINI M.,.' / , S :,..'y uo .tAHE - " , ' -. ,L--

AREA EVALUATED CONDITION

DAM E13ANKNiEIT o, -1,1 _i,1.' Of%. - ,/; :., . y

* Crest Elevation /F3 0

Current Pool Elevation / o

- Maximum Impoundment to Date

Surface Cracks /1/O) v 0, Ile

m Pavement Condition ,// z ;.A' 'F

Movement or Settlement of Crest A'ooe f,' e T

Lateral Movement A/o ,':s /I;,,' e '2 :

Vertical Alignment 7- ai,",4/l ,. # r 2 e,,

Iorizontal Alignment " ,,. .y. . 4/. T

Condition at Abutment and at Concrete /C 7;t,-.,T,,- e r 7Ls _411/F/ /1Structures

Indications of Movement of Structural A/Items on Slopes

" Trespassing on Slopes Av'l, erou3 ;>-/" .4

I Sloughing or Erosion of Slopes or A/04Abutments

Rock Slope Protection - Riprap Failures I/V alo

- Unusual Movement or Cracking at or Near //o;e al Qer e;7Toe

Unusual Embankment or Downstream W/t/ aes o ,/ sces -see 7ex/Seepage

Pipinq or Boils N o - con Cnt- I/ seeps

Foundation Drainage Features

Toe Drains /on

Instrumentation System

Vegetation e 1 e :'r4 /-/ on si ee.

.. . ... - A-2

* : - i , ._ , , -.- . ' : .- " "

- - - - PLRUUII. ff~i'~cioN 'ECKLI

PROJECT DETJR AME _-6

DISCIPLINFjK,,-- ./ ~~a NAfIE 2 ~

AREA EVALUATED ICOND IT]I ONDIKE EMBANKMENT /V 0 / A',''-.

Crest Elevation

Current Pool -Elevation

Maximum Impoundment to Date

Surface Cracks

Pavement Condition

Movement or Settlemient of Crest

Lateral Movement

Vertical Alignment

Horizontal Alignment

Condi tion at Abutment and at ConcreteStructures

Indications of Movement of StructuralItems on Slopes

Trespassing o n Slopes

* Sloughing or Erosion of Slopes orAbutments

Rock Slope Protection - Riprap Failures

Unusual Movement or Cracking at or

Near Toes

Unusual Embankment or DownstreamSeepage

Piping or Boils

Foundation Drainacie Features

Toe Drains

Instrumentation System

Vegetation

A-3

PROJECT ': ' -.. DATE / a/ -,PROJECT FEATURE, NAM 5, 0 '",

DISCIPLINE U I,;'" 9/ f ..t o. NAME . ,

AREA EVALUATED CONDITION

OUTLET WORKS - INTAKE CHANNEL ANDINTAK TRUCT RE

a. Approach Channel //o /-,7 , ,;

.Slope Conditions A o' cJ i-, /lc; -a /'.NBottom Conditions

Rock Slides or Falls

Loq Boom

Debris

Condition of Concrete Lining

Drains or Weep Holes on

b. Intake Structure ./2? / -- /ver Sla, /if/ leve.

PROJECT l-. I, './ DATE /A1y -

PROJECT FEATURE IIAiE 2,i,, Z.z, /

DISCIPLINE V 5V ,w.j Co, NAME -/P-/7", 0. .. ,

e I

AREA EVALUATED CONDITON "

OUTLET WORKS - CONTROL TOWER Aa L"2 O o 0 r/ e9-

a. Concrete and Structural /, ,

General- Condition

Condition of Joints

Spalling . .

Visible Reinforcing

Rusting or Staining of Concrete

Any Seepage or Efflorescence

Joint Alignment

Unusual Seepage or Leaks in GateChamber

Cracks

Rusting or Corrosion of Steel

b. Mechanical and Electrical

Air Vents

Float Wells

Crane Hoist

Elevator

Hydraulic System

Service Gates

Emergency Gates

Lightning Protection System

Emergency Power System

Wiring and Lightinq System

A-5 P

PROJECT -?'r, , *..DATE

PROJECT FEATURE Ou7fi'- .. 1' F/ NAME 5,2 / Z Z

DISCIPLINE . J ;' t', j.,: H,,lAME L

AREA EVALUATED CONDITION

OUTLET WORKS - TRANSITION AND CONDUIT

General Condition of Concrete /-/e-7 -- .-

Rust or Staining on Concrete //" /s ',.

Spalling ' -

Erosion oi Cavitation :/ c',- Co=/OJI / , 4

Cracking" ,',, ,

Al i nment of Monoli ths Ai, , ",

Alignment of Joints n A. ,'/,, . 7P% ', ./j

Numberinq of Monoliths

"i

IPA-6

PROJECT "" . - • DATE ,?!

PROJECT I[A UE . -"' ' ', / .. ),.'.'f NAME , , . , ' ,

[JISCIP I _________-,. - , o, NA E ,,,,, DN AM..

ARIA EVAI.JAi[D CONDITION

a[ Ii ."'!- OUR t T SIRUCTURE AND

Ct - .r4cl Cor,dition of Concrete

Runt or Staining.

Spallinrg

Erosion or Cavitation

Visible Reinforcing

Any Seepage or Ifflorescence

Condition at Joints

Drain holes w-rc -reo ,, -' , .,' ,, , / o

Channel E.. , -,-Y' i O , , , '. i lLoose Rock or Trees Overhanging e 0 e,-17/4

Channel

Condition of Discharge Channel I

A-7

PERIODIC INSPECTION CHECKLIST'

PROJECT ? :/ )6--, DATE /K' "" fTj,

PROJECT FEAIURE 1 02 0 04J6~,,,,, NAME 5, A.A,,~..h

DISCIPLINE NAME.~ ' 7 :'!() /cc) __ _ _ __ _ _ __ _ _ NAE7-~

AREA EVALUATED ICONDITION

OUTLET WORKS -SPILL.WAY WEIR, APPROACH

a. Approach Channel /,

General Condition

Loose Rock Overhanging Channel

Trees Overhanging Channel

Floor of Approach Channel /ax ~~O~%' % -~'~L cu

b. Wei r and1 Trai ni ng Walls \/ .' 9 t.J/'.c

General Condition of Concrete

Rust or Staining pt

Spalling None Wu~b/I.

Any Visible Reinforcing /

Any Seepage or Efflorescence

Drain Holes

c. Discharge Channel

General Condition

Loose Rock Overhanging Channel

Trees Overhanging Channel /vw e e,-, CA 0,1 neC

Floor of Channel t? ae tQ o.'

Other Obstructions e/m

A-8

6 1..>*1 n.3 10

, .77 -.- N .rw-7 17 7

Edward F. Kehoe, Commissioner, Department of Fish and Game

Donald 1f. Spies, Dam Construction Engineer, Depvrtment of Water Resources -

November 5, 1971

Subject: Baker Pond -JBrookfield

On November 1, 1971, the writer inspected the i;ubject structure.

The dam is an e-irth fill structure with a stop lag weir for controlling the

water level and an overflow channel for an emerg,:ncy spillway. At the time

of inspection, two leve.s of stop logs hod been i'emoved. It was noted

that the stop logs had been left on top of the wtir; a pieferable practice 41

would be to put them in storage sonr :where for th. winter.

Structurally, the dam appeared to be ii, good st,ape. There was

one srall cricl noticed in the SoutL! wall, of the stop loE 10eir. The main

problem is the tremendoums amount of sapling grOWLh on the downstream face

of the dz.,n. In addition, there is !;ome scattered brush on the upstream

face and som trees and brush in the riprap on both spilluays. All this

should be cut down.

R~ ~ ~ 0G RALOUTING

ToNbL ED DATE

cc: Richard Sears, Land Negotiator ./1

Robert Collins, Maintenance Supervisor l z. .

HLE -

B-9

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~TT77J7T7L77:B-7 0

2. ~A U. S. -. ta> - - . -.

FILE COPYState of Vermiont

R 0 T IN G A ENCY OF ENVIRONMENTAL CONSERVATION

GENERALI~pit~ict f is aid(~ntTO ?N'TEO DATE Montpelier, Vermiont 05602

IDepaitnitiil of Ioc Pt j 1~rk: .a,i [ccre. ion, 1)E4I)EAIH'!ENT OF WATER RESOURCESLDeparut ncit of WVatr he.>ourCC I) <Envirmrunt titaI Board '-

Divislo, ~ ~ ~ ~ ~ ~ 2 zfHvrriictIEM~ ii AN GEflENT ENGINEERING DIVISIONDivision of Environvititl Pit- 'i _____________________________

0SPEND To January 12, 17

M E M 0 R A N D U It

To: Don Spies

From: Peter lBarranco/Larry Fitch

Subject: Baker Pond Dam - Brookfield

On November 5, 1975 we inspected subject dam. The followingwas noted.

1) Water level cst. 0.1' to 0.2"- above top of dropinlet structure -full column of stop logs in OPplace.

2) Some brush along u/s slopes and uncut grass onslope and crest. Very minor erosion.

3) Heavy brush growth d/s slope.

4) Standing water, swampy on d/s side of "L" at leftend of dam - possibly some quick conditions.Source of water unknown - probably both localdrainage and from impouindment. cl/s slopes weredry. Should be monitored.

S) Emergency spillway unmowed pl1u s s omec b r ush silllllll110right side and generally clear.

Maintenance needs: Cni rush and grass.

API3/vdl

B-6

GENERAL.

601.E January 15, 1976

MEMO11 R AN D1)i

To: Edward F. Kehoe, Comissioner, Dlhpt. of Vish Game

From: Gordon R. Pyper, Commissioner, Dpt. of Ilater Resources

Subj ect: Baker Pond Dam, Brookfiel d

Co I o o m1 S he rb u;j rn e S

Forwarded herewith are copics of inspection roports preparedby engineers from the rManagement Engineering Division, concer-ningtlhc above damns.

Maintenance and observation items are aoted which you may wishto schedule in your future activities.

GRP/DJIM/vdll

Enclosures

B-5

VTZr.ONT DEPART F1T OP IRIT RISOTJRCrPS

IIFOP"ATIO74 SIflT

Nam~e of Tnam 8-k y-RPJ, TownRoki~~d~

4

- Ow erL L/ e, rlw rJ~e of Strowanl Ok

I U. S.'S Coorclinates: La t. //IO T ong. ?,2 3' 1!

U. S. r7. S. Van___________Aeria]. 13hotoJ 2 Jo/

U. 1;. . Elev. 9 Snillway______ ____ ___________

Total Length of r'Mm rres t T 7i(~th of F-me.:raency____* .~Sni 1lwav

'lidth of Ton Iaximum leicylt JZ1Soiliway Canacity: P'rincinal. _______ frmeraency_________

* Pond Area n rrainaae Area___ j__-C3

Pon.1 Volvime: Tlorrmal 'later Level rDesignr Higyh "'ater Level___

TLevelI

Storarie 'lefore Emergencv ISrillw,-v is Tised ___________

Use of Reservoir Y, te a./*ov

* Description of TDarn

Description of Spillway(s):

* Desictned Iy L' ic .Year nuiltL25

I1c~iri nr Datn Opte.er Date Sep

Ari-itional Pirnark-.:

B.-4

0) -

= CD

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0 0 L- L- L C--o 0 0 0 0

4-4 EC0 0. ca. Q- -cm M o 0.) 0.) (U _0(D E -0 f c L- 4)E EL- ) L-

0-J 4-- C c C_ -)4 k- 1L4- 00.) 0 0 0 (DmC - I z - coa- -m 4D 4-1 4J C

D~n 44 ) 0) a) 0-

WL 4J U -ULk In In In NL)C CL E41 C_ C C C-

L. 0- z) tn t - - - knLJ.J WL EQ 0 CO 4-1

(D Lcn m E E E CL ( ICN4co 0)) LD - ) mo rm f 0.)

LI

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n L) 0

BAKER POND DAM

I* EXISTING PLANS O

"Vermont Fish and Game Service"Baker Pond DamBrookfield, Vermont

-- Scale I" = 20'L.M. Laushey, Vt. P.E. #690Northfield, Vt.August 22, 1955Rev. September 6, 1955

"Baker Pond" IOrange County, Brookfield, Vt.Surveyed by Lee H. LowellMay, 1955Scale 1" = 3.00 chains (198 ft.)39.6 Acres

"Contour and Profile of Proposed Dam Sites"Baker PondBrookfield, Vt.By: Lee H. LowellMay, 1955 - Scale: Contour 1" 50'Contour Intervals as shownProfile as shown

''Baker Pond" IBrookf ield, Vt. .-.-Plotted March 27, 1957 -

* Scale 1"= 5'0"

B-2

!.:.-.: .- -.--: .: :.-.. ..--..-...........,....-.......•.....,.-.........-...-.....................,............-..........--......--.....-.......-..

SECT AAto 0 01 10 20

S Or MOO CUTOFF', OUJT MOTTM 1294 OR LOWER

SECT 8B

V 0 Feet 0o 20

SECT CC4 0 i- 4 a

-24'L4

* 'TS PLAN COMPILEO EXO(ISTING PLMA FOIR THEOAM CONSTRUC 7ION IN 1956, MY L N LAIJOHE FOR THEVERMONT FISHt II GAME SERVICE MOFID AS CESEWOIN THE FIELO.

12' THICK

CUT-OFF RINGS(5 REQ'O)

B -If NG,. A"N EAL ONN~ NUR NATIONAL PROGIRAM OF SINIECTIONh

OF MN-PRIM, MGM

V ML AR VN T r BAKER POND DAM

BROOKFIELD, VERMONT

3:z g Xj NVNHIAOU IV JJO(UUUJd3U.....................................................- 7-

- ~ g ~ -~- -,-~ -U -V W S W W ~ v r \ - I -- -1-0 -0

SPIL LWAY

I/-LESS imPERvxOU MOST IMPERVIOVS

SECT AA

-10 1 99

-0A -

1'- 3"

PLANSECT. 85

0 110 0 Feet 0o 20

O le. - 0AD 220S C .

CONTROL CHAMBER

4 0 Feio 4

- - NMORAE0 STONE ±44WING VAL L1

(Roll, 54..(

J~ 12" TI CIICUT-OFF RINGS

(5 REQD)* HEAD WALL

0 4 Feel. 4

I ~ .. .~ ~t. I 4 $~ '--I.. CONSULTINC ENm . -

.77 ~*--~-. - * 3SN3c4XJ .0NjXqkNJA00 IV~ UjiJi1UUddJdi

REPRODUCED AT GOVEAKJMEN-1 FXPFNSE -

A4

v________________ _______________________

wt.

O~ 1j 0

- - ./ j/ // /77/ /'//NV~d &;b7 /'7/'~ 7 /

F

I i APPENDIX B

ENGINEERING DATA

iii

.9 PROJECT 3 "e, vj 9r DAT E. /~PROJECT FEATURE _ _ _ _ _ _ _ _ __ NAME S, d,1 /V,~ ,

DISCIPLINE >, >:. C NAME ./', ,,PL

AREA EVALUATED CONDITION

OUTLET WORKS -SERVICE BRIDGE

a. Super Structure

Bearings

Anchor Bolts

- . Bridge SeatA

Longitudinal Mlembers

Underside of Deck

Secondary Bracing.

Deck

Drainage System

* Railings

Expansion Joints

Paint

* b. Abutment &Piers -. Ar9

General Condition of Concrete

Alignment of Ahutmnent

Approach to Bridge

Condition of Seat Backwiall

ji

A-9

~F~RoflU(1sr) A~ COVrR9~M~N1 ~- %PFNSI~

A -I..-. - .. ,;~;- -'~A.

N -

7/ I.:1I*'

7.

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a ~... -o ~11 0/

t.i 0~'2V am,1

0 I.

APPENDIX C

DETAIL PHOTOGRAPHS

*1

U 0

-0

a

D 0 m

I00

C

a-1

(1) Rock outcrop Near Left Abutment

(2) Upstream Slope, From EmergencySpill way

U.SARMY ENGINEER DIV, NEW ENGLAND Baker Pond DamCORPS OF ENGINEERS

WALTHAM, MASSACHUSETTS NATIONAL PROGRAM OF Brookfield, VermontINSPECTION OF _VT 00135

JAMES W. SEWALL COMPANYNO-E.DMMa5,984CONSULTANTSNO-E.DMMa5,98

OLD TOWN, MAINE C

~'k& 4 O..

414

(4) Crest of Dam, from Rock Outcrop

U.SARMY ENGINEER DIV, NEW ENGLAND Baker Pond DamCORPS OF ENGINEERS NATIONAL PROGRAM OF Brookfield, Vermont

WALTHAM, MASSACHUSETTS ISETO FV 03

JAMES W. SEWALL COMPANYNOFE.DMMa .104CONSULTANTSNO-E.DMMa5 18OLD TOWN, MAINE C-3

. u . 7

nrPRoiflJCFfl AT GO0VFRNMENT FXPEI-JSE

(5) Growth on Downstream Slope

(6) Area of Flow from BeneathRoot Mat at Toe of Dam

pa

U.SARMY ENGINEER DIV. NEW ENGLAND Baker Pond DamCORPS OF ENGINEERS NATIONAL PROGRAM OF Brookfield, Vermont

WALHAM MASACU~ETSINSPECTION OF VT 00135

JAMES W SEWALL COMPANY NNFD DASMay 5, 1980*CONSULrA4TS NOSE.DM -

010 TOWN, MAINE 7 -

I-L

U

(7) Silt Deposit from Seepage at (8) Seepage Draining TowardToe of Dam Outlet Channel

U.S.ARMY ENGINEER DIV. NEW ENGLAND Baker Pond DamCORPS OF ENGINEERS NATIONAL PROGRAM OF Brookfield, Vermont

WALTHAM, MASSACHUSETTSINSPECTION OF VT 00135

JAMES W. SEWALL COMPANY NON-FED. DAMS May 5, 1980CONSULTANTS

OLD TOWN, MAINE C-5... .. . . - , . . . . . . . . . .

(9) Seepage Entering Outlet Channel

(10) Outlet Structure

U.SARMY ENGINEER DIV, NEW ENGLAND Baker Pond DamCORPS OF ENGINEERSNAINLPORMO B ok eIdVrmn

* ~~WALTHAM, MASSACHUSETTSNAINLPORM F BrofedVrmnINSPECTION OF _VT 0013q

JAMES W. SEWALL COMPANY NON-FED. DAMS May 5, 1980CONSULTANT SC-

OLD TOWN, MAINE _______________

(11 Dicag Pip fro OultStutr

AA

(12) Emergency Spillway Channel

U.S.ARMY ENGINEER DIV, NEW ENGLAND Baker Pond DamCORPS OF ENGINEERS NATIONAL PROGRAM OF Brookfield, Vermont

WALTHAM, MASSACHUSETTSINSPECTION OF VT 00135

JAMES W. SEWALL COMPANY N -FD DASMay 5, 1980CONSULTANTS NO-E.DM

OLD TOWN, MAINE _______-7__________

APPENDIX D

H-YDRAUL ICS/HYDROLOGIC COMPUTAT IONS

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1. 1 (

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Civil and Sanitary Engineers Sheet of L __ .0

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Civil and Sanitary Engineers Sheet- of

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Civil and Sanitary Engineers Sheet ofI

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Civil and Sanitary Engineers Sheet 17 of

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PRELIMINARY GU IDAN~CE

FOR ESTIMATING

MAXIMUM PROBABLE DISCHARGES

- IN

PHASE I DAM SAFETY

I.NVESTIGATIONS

New England DivisionCorps of Engineers

March 1978

D-19

. ....... . % . .:

S. -

M-XIMJM PROBABLE FLOOD INFLOWSI U " NED REsERvoIuS

Proect R D.A. MPF(cfs) (sq. mi.) cfs/s-q. mi.

1. Hall Meadow Brook 26,600 17.2 1,546

S. East Branch 15,500 9.25 1,6753. Thomaston 158,000 97.2 1,625

4. Northfield Brook 9,000 5.7 1,5805. Black Rock 35,000 20.4 1,715

6. Hancock Brook 20,700 12i.0 1,725

7. Hop Brook 26,400 16.4 1,610

8. Tully 47,000 50.0 940

9. Barre Falls 61,000 55.0 1,109

10. Conant Brc;ok 11,900 7.8 1,525

- 11. Knightville 160,000 162.0 987

[ .12. Littleville 98,000 52.3 1,870

[-13. Colebrook River 165,000 118.0 1,400

{,14. Mad River 30,000 18.2 1,650

15. Sucker Brook 6,500 3.43 1,895

B16. Union Village 110,000 126.0 87317. North Hartland 199,000 220.0 904

18. North Springfield 157,000 158.0 994

19. Ball Mountain 190,000 172.0 1,105

20. Townsbend 228,000 106.0(278 total) 820

21. Surry Mountain 63,000 100.0 630

22. Otter Brook 45,000 47.0 957

23. Birch Hill 88,500 175.0 505

24. East Brimfield 73,900 67.5 1,095 ,•:25. Westville 38,400 99.5032 net) 1,200

26. West Thompson 85,000 173.5(74 net) 1,150

27. Hodges Village 35,600 31.1 1,145

28. Buffumville 36,500 26.5. 1,377 .29. Mansfield Hollow 125,000 159.0

786

30. West Hill 26,000 28.0 928

31. Franklin Falls 210,000 1000.0 210

32. Blackwater 66,500 128.0 520

33. Hopkinton 135,000 426.0 316

34. Everett 68,000 64.0 1,062

35. MacDowell . 36,300 44.0 825 * S

D-20

MAXIMUTM PROBABLE FLOWS /.BASED ON TWICE THE

STANDARD PROJECT FLOOD(Flat and Coastal Areas)

* - River SPF D.A. 1,P?(cfs) (sq. mi.) (cfs/sq. mi.)

1. Pawtuxet River 19,000 200 190

* 2. Hill River (R.I1.) 8,500 34 500

3.Peters River (R.I.) 3,200 13 490

4. Kettle Brook 8,000 30 530

5. Sudbury River. 11,700 86 2.70-

6. -Indian Brook (Hopk.) 1,000 5.9 340

7. Charles River. 6,000 184 65

8. Blackstone River. 43,000 416 200

9. Quinebaug River 55,000 331 330

a.-

D-21 0-

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~~v.~D 42,~ _ I 13-1 N~i *0 S0'lDNI z d

ESTIMATING EFFECT OF SURCHARGE STORAGEON MAXIMAUM PROBABLE DISCHARGES

OUTFLOWW

T4

STEP 1: Determine Peak Inflow (Qpl) from Guideit Curves.

* STEP 2: a. Determine Surcharge Height To PasS.' 'cQp '

b. Determine Volume of Surcharge(STORi In Inches of Runoff.

C. Maximum Probable Flood Runoff In NewEngland equals Approx. 19". Therefore:

Qp2 Qp x 1 - STORI)19

* STEP 3: a . Determine Surcharge Height and." STOR2'" To Pass "Qp 2'r

b I. Average "STORi" and 'STORz'" andDetermine Average Surcharge and

Resulting Peak Outflo-w ''Qp3''.*Q-2

V /

"RULE OF THUMB" GUIDANCE FOR ESTIMATING'DOWNSTREAM DAM FAILURE HYDROGRAPHS

-4 .',QpT 12 S

K-3

T1

T3

STEP I t DETERMINE OR-ESTIMATE RESERVOIR STORAGE (S) IN AC-FT AT TIME OF FAILURE.STEP 2: DETERMINE PEAK FAILURE OUT'FLOW (Qpl)*,

%7 b --r

Wb= BREACH WIDTH - SUGGEST VALUE NOT GREATER THAN 40% OF DAM.LENGTH ACROSS RIVER AT MID H'EIGHT.

Yo TOTAL HEIGHT FROM RIVER BED TO POOL LEVEL AT FAILURE.

*STEP 3: USING USGS TOPO DR OTHER DATA, DEVELOP REPRESENTATIVE STAGE-DISCHARGERATING FOR SELECTED DOWNSTREAM RIVER REACH.

- STEP 4: ESTIMATE REACH OUTFLOW (Q 2) USING FOLLOWING ITERATION.A. APPLY Q TO STAGE RATING, DETERMINE STAGE AND ACCOPHANYING

VOLUME (VI) IN REACH IN AC-FT. (NOTE:. IF VI EXCEEDS 1/2 OF S.

* SELECT SHORTER REACH.)

S. DETERMINE TRIAL Q

Op (TRIAL)= Op (17 )C. COMPUTE V2 USING Q (TRIAL).D. AVERAGE V1 AND V2 AND COMPUTE Q~2

a Op 2 z Op, (I - ~

STEP 5: FOR SUCCEEDING REACHES REPEAT STEPS 3 AND 4.APRIL 1978

D-24

I" LENGTH. ACOS RIE AT MI .EIGHT. _

1 APPENDIX E

INFORMATION AS CONTAINED IN

THE NATIONAL INVENTORY OF DAMS

FILMED

8-85

DTIC