Nitrogen in Minnesota StreamsResearch continues on possible game-changers i.e. economically viable perennial energy crops Collaboration increasing Minnesota Nutrient Reduction Strategy

Nitrogen in Minnesota Streams Sources, loads and transport

Dave Wall

with David Mulla, Steve Weiss, Dennis Wasley and David Lorenz October, 2012

Nitrogen in Minnesota Surface Waters – comparing watersheds, sources, trends and solutions Major Rivers - loads and concentrations

HUC8 watershed conditions

N transport and transformations

Trends

Sources

Verification of source assessment

Tools for evaluating solutions

Report - 2013

Collaborative Study

MPCA – Steve Weiss, Dennis Wasley, Tom Pearson, David Christopherson, Pat Baskfield, Mark Tomasek, et al.

University of Minnesota – David Mulla, Jake Galzki, Karina Fabrizi, William Lazarus, Mae Davenport, Ki-In Kim, Carl Rosen, Bjorn Olson, Geoff Kraemer

USGS – Dave Lorenz, Dale Robertson, David Saad, Gary Martin

Metropolitan Council – Karen Jensen, et al.

MDA – Joshua Stamper, et al.

3

Concern: Nitrogen in Surface Waters

Downstream Loads

Gulf of Mexico

Lake Winnipeg

In-State Concentrations

Aquatic life toxicity

Drinking water

4

Mississippi River at Iowa

211 million lbs/yr TN (avg)

77% from Minn. watersheds

75% in Nitrate form

Nearly half from Minnesota River Basin

Peaks April-June

5

Transport to Gulf of Mexico

6

Red River at Canada

37 million lbs/yr TN (avg)

48% from MN watersheds

7

Concern: Nitrogen in Surface Waters

Downstream Loads

Gulf of Mexico

Lake Winnipeg

In-State Concentrations

Aquatic life toxicity

Drinking water

8

Stream Nitrate Concentrations 90th percentiles 2000-2010

9

10

Comprehensive Nitrogen Study for Minnesota

informs

Minnesota Nutrient Reduction Strategy

In-state and downstream

concerns

N standards for MN streams under development

Gulf of Mexico Hypoxia Task

Force

Nitrogen Study - Key Questions

1. What are the N conditions?

2. Where is most N coming from?

• Geographically

• Sources

• Pathways

3. What are the trends?

• Next talk – D. Lorenz

4. How much N is lost within surface water?

5. How much can N be reduced?

11

SPARROW Modeling

Total Nitrogen Yield (lbs/ac)

S. Central 16-22

Metro 17

Southeast 9-15

Southwest 8-15

Central 3-6

Northwest 3-6

Northeast 0-2

Monitoring

Nitrite+Nitrate-N Yield (lbs/ac)

S. Central 11-19

Southeast 8-9

Southwest 4-9

Central 1-2

Northwest 0.1-1

Northeast 0.1-2

Sources & Pathways

Nonpoint Sources

U of M – Dr. David Mulla et al

Field/local scale research multiplied by GIS data

Point Sources

MPCA

Permit Data

Atmospheric Deposition

EPA model

Monitoring

14

Statewide N Sources to Soil cropland and other land

15

0

200

400

600

800

1000

1200

1400

1600

18001728

1359

612

446

217

2

218

12 9

Annual N

itro

gen (m

illion lb

s/yr)

6% of

cropland N

reaches surface

waters

Statewide N Sources to Surface Waters (average year)

16

0

20

40

60

80

100

120

140

Annual N

itro

gen (m

illion lb

s)

Point Sources

Atmos. Into waters

Feedlot

Septic

Urban NPS

Forest

Ag. Runoff

Ag. Drainage

Ag. Groundwater

18

Wet Year – N Sources to Surface Waters

Sources & Pathways (statewide to streams)

Pathways dominated by subsurface transport 73% average year 82% wet year

Urban areas contribute some N 10% average year per acre contributions similar to cropland Municipal wastewater most of urban N

Cropland is dominant source statewide 72% average year 83% wet year Varies greatly by crop, soils, drainage, mgmt & climate

Other sources minor low N loads and/or concentrations

UMN/MPCA Source Assessment

Checked against

1. Sparrow model

2. Load monitoring

3. Statistical analyses

4. HSPF model

5. Literature reviews

20

SPARROW Model Source Estimates Compared to UMN/MPCA Assessment

21

Load Monitoring compared to UMN/MPCA source assessment

22

Statistical Analyses Results consistent with UMN/MPCA source assessment

23

y = 19.235x - 0.3528

R² = 0.96

0.00

2.00

4.00

6.00

8.00

10.00

12.00

0.0% 10.0% 20.0% 30.0% 40.0% 50.0% 60.0%

Nit

rite

+N

itra

te-N

FW

MC

(m

g/l)

% of watershed in row crop over tile, sand, or shallow bedrock

Nitrate Concentration vs. % leaky row crop land

HSPF Model Results Compared to UMN/MCPA Source Assessment

Minnesota River Basin only

24

HSPF UMN/MPCA

subsurface pathways 89% 94%

urban stormwater + feedlot runoff + forest

2.4% 1.5%

N loads - wet years compared to average years

179% 170%

Reasonably well understood about N

Statewide and Basin levels

Sources

Transport pathways

Effects of precipitation

High loading watersheds

How much is transported downstream

25

Developed in 2012 by Univ. of MN W. Lazarus, D. Mulla, et al.

For HUC8 watershed scale use, or statewide

Estimates for watershed BMP adoption scenarios Costs

N reductions in waters

Nitrogen Reduction Planning Tool for Watersheds

BMP options in spreadsheet

N rates

Fall to Spring N

Sidedressing N

Wetland Treatment

Bioreactors

Controlled drainage

Cover crops

Perennial vegetation on marginal lands & riparian

Planning Tool Shows

Large scale BMP adoption needed for measurable reductions in water Source reductions

Intercept and treat technologies

Vegetative scavengers

N reductions to streams with broad adoption of BMPs ~ 15-20% Statewide

~ 20-30% Heavily tiled watersheds

~ 10-15% Non-tiled watersheds

Costs increase markedly after first 10-15% reduction

27

Rays of Hope…

Some solutions have multiple benefits

Room for progress with existing BMPs

Research continues on possible game-changers i.e. economically viable perennial energy crops

Collaboration increasing Minnesota Nutrient Reduction Strategy

Iowa, Wisconsin, others working on this issue

Solutions?

Questions

Thank You

Dave Wall

651-757-2806

[email protected]

Trends in Nitrite plus Nitrate Concentrations in Selected Streams in

Minnesota, 1968–2009 Minnesota Water Resources Conference

October 16-17, 2012

St. Paul, MN

U.S. Department of the Interior U.S. Geological Survey

A cooperative project by the USGS and MPCA

Dave Lorenz, USGS, Mounds View, MN Dave Christopherson, MPCA, St. Paul, MN

Gary Martin, USGS, Louisville, KY Dave Wall, MPCA, St. Paul, MN

2

Why Analyze Trends?

• Clean Water Act Passed in 1972, the act established the goals of eliminating releases of high amounts of toxic substances into water, eliminating additional water pollution by 1985, and ensuring that surface waters would meet standards necessary for human sports and recreation by 1983.

3

How to Analyze Trends?

• Short-term, Monotonic Trends

Season

NO

x co

ncen

tratio

n

01

23

1 2 3 4 5 6

S000-183

TrendsOverallSeasonal

Conce

ntr

ation

4

How to Analyze Trends?

• Long-term, Dynamic Trends Com

mon log r

esi

duals

5

How to Analyze Trends?

• Long-term, Dynamic Trends

6

What are the Short-

term Trends?

Trends 1990-2010Up at .1Up at .5None at .5Down at .5Down at .1

-96 -94 -92 -90

44

45

46

47

48

49

195

159299

139 054

163134

040MI39.4

310

7

What are the Long-term Trends?

8

Pomme de Terre

Yellow Med.

Redwood

CottonWood

9

Yellow Med.

Redwood

Cottonwood

Minn. Courtland

10

Cottonwood

Minn. Courtland

Watonwan

Blue Earth

11

Minn. Courtland

Watonwan

Blue Earth

Minn. Henderson

12

Blue Earth

Minn. Jordan

Minn. Airport

Minn. Henderson

13

Summary

• Some trends are up, some are down

• Only fair agreement between the short-term trend results and the last few years of the long-term results

• Long-term results presented for Minn. R. only

• Final report looks at 54 long-term sites, 56 20-year sites and 41 10-year sites

14

QUESTIONS?

http://mn.usgs.gov

Central Sands Private Well Network 2011 Nitrate-N Sampling Results

Kimberly Kaiser

Minnesota Department of Agriculture

Fertilizer Management Unit

2012

• 14 Counties make up

the Central Sands

Region

• The Central Sands

Region is characterized

by sandy outwash

glacial plains that are

highly susceptible to

surface activities.

• High value crops such as edible beans, corn and potatoes dominate the landscape.

• Intensely irrigated.

• MDA has been monitoring groundwater since 1987. • In 2000, a statistically designed network was installed to sample the water table at

the edge of fields. • Since 2000, quarterly median results of this network have been over 10 mg/L.

MDA Monitoring

Network Wells

MDA Summary of Nitrate Nitrogen Data: http://www.mda.state.mn.us/~/media/Files/chemicals/maace/2012-03nitraterpt.ashx

PROJECT GOALS Phase 1.

Short term goal: Determine current nitrate concentrations in private wells throughout the Central Sands region. What are people drinking?

Identify Areas of Concern. Phase 2.

Long term goal: Determine long-term trends; whether nitrate concentrations are stable, increasing, or decreasing.

Continue to assess Areas of Concern

This approach is modeled after a pilot project

in Southeastern Minnesota:

Volunteer Nitrate Monitoring Network

Partners/cooperators:

MDA

PCA

MDH

Southeastern Minnesota Water Resources Board

http://www.winona.edu/geology/WRB/WRB/Downloads/SEMWRB%20Final%20Report%20VNMN%2012.31.2009%20.pdf

• In order to accomplish the goals of the first phase, MDA established a grant project with the Wadena county SWCD. MDA developed the design and the original parcel list. Wadena coordinated the survey work and sample analyses.

• An unaligned randomly started grid was placed over the 14 counties. • Grid nodes are approximately 2 miles apart.

• Grid nodes that were in township with < 20% row crops, were clipped out. • Municipalities and public land were also clipped out.

1. A 1.5 mile buffer was drawn around each grid. 2. The buffers were then placed over parcel data.

Homesteaded with building values > $20K. Approximately 2300 buffers.

3. 3 parcels were randomly selected from each buffer.

4. Each received an invitation letter and survey about their well.

1. Where did the water sample come from? 1 Sub-division 2 Lake Home 3 Country 4 Municipal (If municipal well, stop here and return form, you will not be included in the private well network.)

2. If the water sample came from the country, do you have livestock (more than 10 head of cattle, 30 head of hogs or an equivalent number of other livestock)? 1 Yes 0 No 3. If the sample came from the country, do you mix or store fertilizer (500 lb. or more) on the farm site? 1 Yes 0 No

4. Does farming take place on this property? 1 Yes 0 No 5. Does your well have a county well index number? Yes or No (found on your well casing)

If yes, what is the County Well Index number? ________________or don’t know________ (found on your well casing) 6. Approximate age of your well? 1 0 - 10 years 2 11 - 20 years 3 21 - 50 years 4 over 50 years

7. Approximate depth of your well? 1 0 - 50 Feet 2 51 - 100 feet 3 100 - 300 feet 4 over 300 feet

8. Distance to an active or inactive feedlot? 1 0 - 50 Feet 2 51 - 100 feet 3 100 - 300 feet 4 over 300 feet 9. Distance to a septic system? 1 0 - 50 Feet 2 51 - 100 feet 3 100 - 300 feet 4 over 300 feet

10. Distance to an agricultural field? 1 0 - 50 Feet 2 51 - 100 feet 3 100 - 300 feet 4 over 300 feet

11. Type of well construction? 1 Drilled 2 Sand point 3 Hand dug well 4Flowing 5 Other 12. Is this well currently used for human consumption (Drinking or Cooking)? 1 Yes 0 No

13. Please check any water treatment you have other than a water softener. 0 None 1 Reverse Osmosis 2 Distillation 3 Filtering system 4 Other

14. When did you last have your well tested for nitrates, lead, hardness, bacteria, etc.?

1 Never tested 2 Within the past year 3 Within the last 3 years

4 Within the last 10 years 5 Greater than 10 years 6 Don’t remember

Final Sample Status of the Well Survey performed by

The Minnesota Center for Survey Research-U of M

A total of 6605 surveys were sent out to parcel owners.

2989 (46%) returned a completed survey.

1822 of the 2989 were sent a water sample kit, 1167 were

not. Which means that more than one well owner

responded per buffer- good response!

• 1822 well owners were sent a sample kit that contained a bottle, sampling instructions, and a prepaid mailer to send the sample back to the lab.

• 1555 well owners sent in their water sample.

1555 wells were sampled in the first phase.

88%

7% 5%

2011 Private Well Network Nitrate-N Sampling Results

Nitrate-N <3 mg/L

Nitrate-N 3-10 mg/L

Nitrate-N ≥10 mg/L

County Number of

Samples Min Median Max

% at or below

3 (mg/L)

% between 3

-10 (mg/L)

% at or

above 10

(mg/L)

Becker 123 <.03 <.03 15.4 93% 5% 2%

Benton 57 <.03 <.03 15.6 79% 12% 9%

Cass 82 <.03 <.03 9.5 96% 4% 0%

Crow Wing 66 <.03 <.03 8.3 92% 8% 0% Douglas 90 <.03 <.03 8.8 94% 6% 0% Hubbard 65 <.03 <.03 29.3 85% 8% 8%

Kandiyohi 117 <.03 <.03 38.7 93% 3% 4%

Morrison 124 <.03 <.03 33.9 78% 11% 11%

Ottertail 320 <.03 <.03 32.7 90% 4% 5%

Pope 93 <.03 <.03 35.0 94% 1% 5%

Sherburne 42 <.03 <.03 40.0 91% 5% 5%

Stearns 167 <.03 <.03 49.8 82% 13% 4%

Todd 137 <.03 <.03 81.0 93% 5% 2%

Wadena 72 <.03 0.09 49.2 75% 17% 8%

Average 1,555 total

samples <.03 0.01 31.9 88% 7% 5%

Central Sands Private Well Network 2011 Nitrate-N Results Summary

• Nitrate concentrations vary greatly over short distances.

• Clusters of wells with high concentrations are observed.

• Wells that are located in high water table sensitivity are significantly different than wells in the low and medium sensitivity combined. (Kruskal-

Wallis non-parametric method)

0

5

10

15

20

25

30

35

40

45

50

0

2

4

6

8

10

12

Hand Dug(30)

Sandpoint (139) Drilled(1298)

Other(90)

Per

cent

> 1

0 m

g/L

Nitr

ate-

N m

g/L

Well Construction Type

Well Construction and Nitrate Concentrations

Average

%>10

Median

0

5

10

15

20

25

30

35

40

45

50

0.0

1.0

2.0

3.0

4.0

5.0

0 to 50 51 to 100 101 to 300 Over 300 DK

Per

cent

> 1

0 m

g/L

Nitr

ate-

N m

g/L

Depth in Feet

Well Depth and Nitrate-N Concentrations

Average

%>10

Median

236 668 505 21 125

0

5

10

15

20

25

30

35

40

45

50

0

1

2

3

4

5

0 to 10 11 to 20 21 to 50 > 50 DK

Well Age in Years

Per

cent

ant >

10

mg/

L

Nitr

ate-

N m

g/L

Well Age and Nitrate-N Concentrations

Average

%>10

Median

368 133 572 406 76 # of Wells

First Phase Summary 1555 Well owners were the cornerstone of this project. Nitrate-N concentrations are lower in the private wells

than in the MDA monitoring wells. Well construction, well depth, and well age are important

factors affecting the quality of water in private wells.

Phase 2: A new joint powers agreement between MDA and Wadena SWCD was developed to establish a long-term network

Sample kit preparation

Sample kit mailing, sample tracking, and receiving

Phone calls, coordinating with 13 other counties

Sample analysis - the table top UV-spectrophotometer is used to analyze samples in the long-term network.

Wadena SWCD was responsible for:

Ultra-Violet Spectrophotometers allow rapid and accurate nitrate-nitrogen analysis

• The UV method requires no reagents or time for color

development

Phase 2:

Volunteers

All well owners from the 1st phase were invited to participate in the long-term network.

MDA planned to continue this network for as many as

800 wells.

Approximately 550 well owners were willing to continue the annual sampling.

Phase 2:

Site Visits

Each well in the second phase will be visited by a county well coordinator.

A water planner or water technician from each county was trained to perform the well site visits. This was done in cooperation with the Minnesota Department of Health, Jim Lundy.

Phase 2:

Site Visits Training

Step 1: Get Organized. Collect all of the available information about the well.

Step 2: Collect Information at the Well Site.

Step 3: Collect Information About Potential Nitrate

Sources.

Step 4: Verify the Well Location.

• Well depth • Casing diameter • Well age • Geologic material • Grouted?

Well Logs Provide:

Step 3: Collect Information About Potential Nitrate Sources

Each county will provide MDA the information obtained from the well site visits.

The information from the well site visits will be analyzed.

Phase 2: Data Transfer/Analysis

89%

8%

3%

Nitrate-N <3 mg/LNitrate-N 3- 10 mg/LNitrate-N ≥ 10 mg/L

Central Sands Private Well Network 2012 Nitrate-N Results

Approximately 500 well owners have returned samples for 2012

Continue monitoring with the participating volunteers. Aquifer designation using well log information into

database Find ways to keep the volunteers involved and interested. Prioritizing areas of concern, targeting townships for

Nitrate-N sampling

What’s Next???

• http://www.mda.state.mn.us/protecting/cleanwaterfu

nd/gwdwprotection/characterizingnitrates.aspx

Contact info:

Kimberly Kaiser

651-201-6280

[email protected]

Questions or Comments?