Overview of the Revised Minnesota Nitrogen Fertilizer Management Plan. Bruce Montgomery and numerous staff at the MN Department of Agriculture

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1 Overview of the Revised Minnesota Nitrogen Fertilizer Management Plan Bruce Montgomery and numerous staff at the MN Department of Agriculture

2 Trends in Acres of Leaky Crop Rotations and Nitrogen Fertilizer Sales Acreages of Leaky Crops (Millions) Cumulative Acres of Corn, Soybeans, Edible Beans, and Potatoes Statewide Nitrogen Fertilizer Sales Tons of Nitrogen

3 An Outcome of the 1989 Groundwater Protection Act- Nitrogen Fertilizer Management Plan (NFMP) The NFMP is the state s blueprint for minimizing groundwater impacts from the use of nitrogen fertilizer

4 The NFMP (1990) provided the framework for a variety of activities including.. Development of voluntary Best Management Practices (BMPs); Promotion of BMPs via education and demonstration projects; Evaluation of BMP adoption and effectiveness; and A process for going to regulations if BMP implementation steps are proven ineffective

5 The NFMP Review Process The NFMP just went through an extensive two-year review process with the assistance of numerous organizations and agencies

6 NFMP Advisory Committee Agricultural Water Resources Center (MAWRC) Area II Potato Growers Council Corn Growers Association (MCGA) Crop Production Retailers (MCPR) Minnesota Independent Crop Consultant Association (MICCA) Board of Soil and Water Resources (BWSR) Department of Health (MDH) Department of Natural Resources (MDNR) Pollution Control Agency (MPCA) Environmental Quality Board (EQB) The Nature Conservatory (TNC) The Freshwater Society Dakota County Water Management Rock County Land Management Office / SWCD Fillmore SWCD UM, Department of Soil, Water and Climate UM Extension UM Water Resource Center

7 Currently in the Public Review Process Comment period August 2 November 1 View draft plan at:

8 Basic Concept of the NFMP Voluntary Regulatory Nitrate Levels Acceptable Not Acceptable BMP Adoption Acceptable Not Acceptable

9 MDA has a 20+ Year History Working with Farmers and Communities Many tools and approaches in the revised NFMP were developed from successes learned from a small number of Source Water Protection Areas (public water suppliers)

10 Revised NFMP: Clear Definition of Prevention & Mitigation Phases Prevention Phase One Phase Two Phase Three Phase Four Nitrate Levels Increasing BMP Adoption Acceptable or Undetermined Not Acceptable Regulatory Status Voluntary Regulatory

11 Prevention Designation will Cover a Vast Majority of Minnesota Phase Develop Phase a new Nitrogen Phase Phase Prevention One Fertilizer Two Education Three and Four Promotion Team to support and coordinate Develop a Nitrogen prevention Fertilizer activities Acceptable Integrate Education prevention and Promotion activities Team with to support other water and coordinate protection activities prevention such activities; as local water Undetermined plans, Integrate watershed prevention plans activities and source with other water water protection protection plans (surface waters) activities such as local water Voluntary plans, watershed plans and source water protection plans Nitrate Levels BMP Adoption Regulatory Status

12 NFMP Priorities: 1) Source Water Protection Areas (groundwater) 2) Private wells within impacted townships demonstrating local support and capacity

13 Other New Features of the NFMP Includes a process for accelerating the knowledge on the severity and magnitude of current NO 3 -N concentrations in private wells; Will use GIS data layers to help identified problematic areas; Will now operate primarily on a township scale for most activities;

14 New NFMP Feature: Clear Definition of Nitrate Criteria within the Mitigation Phases Phase One Phase Two Phase Three Phase Four Nitrate Levels Increasing % Number of Private Wells 5% or More Above 10 mg/l OR 10% or More Above 7 mg/l 10% or More Above 10 mg/l 15% or More Above 10 mg/l

Ambitious Nitrate Assessment Goals: Characterizing 230-280 Townships Private wells within 230-280 townships may be at risk; MDA and local partners will be

15 Ambitious Nitrate Assessment Goals: Characterizing Townships Private wells within townships may be at risk; MDA and local partners will be assessing townships over the next two years; If funding continues to be available, ALL identified townships will be tested in six years (70,000 households)

16 Homeowner Participation is the Cornerstone of the Township Testing Approach Through direct mailings, we can quickly conduct a township snapshot based upon a response rate typically between 30-60%

17 Prior to Making a Phase Determination, the Data Must be Reviewed and Screened If more than 5% of the participating wells are greater than 10 mg/l then some additional investigation and data analysis is required; Wells impacted by other potential sources, such as septics and adjacent feedlots, need to be screened out of the data sets; Additional guidance provided in Appendix H

18 A Township has been found to have ambient nitrate levels exceeding the new NFMP criteria.. Now What? This township is now classified as either a Phase 1 or Phase 2 Phase One Phase Two Phase Three Phase Four % Number of Private Wells 5% or More Above 10 mg/l OR 10% or More Above 7 mg/l 10% or More Above 10 mg/l 15% or More Above 10 mg/l

19 Local Involvement is Critical in ALL Phases Local Advisory Team including local government; Participation of local farmers and their crop advisors is critical; and Site specific strategies are needed We will have more detailed discussions about the potential role of SWCD, Environmental Health Offices and Township Boards at the upcoming MN Association of SWCD Annual Meetings in December

20 Successful BMP Adoption? Additional Details A few words about BMP Adoption. Accurate Assessment is Critical in Phase One LIMITED INFO COLLECTED Based upon input from ag retailers and crop consultants Phases 2,3 and 4 Phase Two Either already YES or after successful educational efforts Benchmark Conducted and Subsequent Assessments Verify Adoption Phase Three NO Based upon Assessments in Phase Two and Current Required Reporting Phase Four NO Based upon Assessments in Phase Two and Current Required Reporting

21 The NFMP Highly Dependent on Voluntary BMPs As long as farmers readily adopt these cost effective practices, it is very unlikely regulations on nitrogen fertilizers will be developed

22 Revised NFMP. Recognition of the Limitation of BMPs in Highly Vulnerable Areas Some highly groundwater sensitive areas, despite 100% adoption of BMPs, may not be adequately protected from nitrate contamination; The concept of Alternative Management Tools should be considered;

23 Alternative Management Tools Alternative Management Tools (AMTs) go beyond BMPs in terms of reducing nitrate leaching losses; Frequently, AMTs are not economical for the producer; Will usually require external funding; and They tend to be very site specific in nature

24 Examples of Alternative Management Tools Introduction of perennials or CRP into targeted areas (Perham and Verdi); CRP/Hunting Preserve Example (Holland); Introduction of lower nitrogen use potato varieties (Perham and Park Rapids); Land swapping (Perham); Installing easements in sensitive areas

25 When Does the NFMP Go Regulatory? Phase One Phase Two Phase Three Phase Four Nitrate Levels Successful BMP Adoption? If 5% water or More of quality is not Wells Above 10 acceptable and 10% farmers or More mg/l OR have Above 10 mg/l 10% chosen Above not to adopt 7 mg/l the voluntary BMPs, MDA will take the lead in developing YES NOT DETERMINED Benchmark Conducted rules in accordance and Subsequent with Assessments the processes and guidance outlined in the Groundwater Protection Act Regulatory Status Voluntary Voluntary 10% or More Above 10 mg/l NO Based upon Assessments in Phase Two and Current Required Reporting Example: Mandatory Reporting 15% Above 10 mg/l NO Based upon Assessments in Phase Two and Current Required Reporting Example: Mandatory Reporting And Restricted Practices

26 Transition from Phase 2 to Phase 3/4 What Are the Timelines for BMP Adoption? The Revised Plan proposes that a period of not less than one crop rotation to allow for the adoption of BMPs The local advisory team will need to decide if the education/awareness was sufficient

27 In a Nutshell, Revised NFMP. Phase One Phase Two Phase Three Phase Four Nitrate Levels 5% or More of Wells Above 10 mg/l OR 10% Above 7 mg/l 10% or More Above 10 mg/l 15% Above 10 mg/l Successful BMP Adoption? NOT DETERMINED YES Benchmark Conducted and Subsequent Assessments NO Based upon Assessments in Phase Two and Current Required Reporting NO Based upon Assessments in Phase Two and Current Required Reporting Regulatory Status Voluntary Voluntary Example: Mandatory Reporting Example: Mandatory Reporting And Restricted Practices

28 Take Home Messages We believe that the Plan is a logical and flexible approach for dealing with a very complex system; The revised Plan is built upon the knowledge gained from the 20 years of experience working with farmers and communities; The Plan is heavily dependent upon education and local problem solving; and Township Testing will be the launching pad for the NFMP characterizing current nitrate conditions in private wells across townships

29 Thank You!

30 Conditions Sources Trends Reductions

31 Report finalized June 2013 Others

32 Prompted study 2010 Legislative Session Laws Ch. 361 Gulf of Mexico Hypoxia Task Force Action Plan

33 Why we did this study Minnesota waters Downstream waters Aquatic life toxicity MPCA developing standards (2015) Drinking water in streams 15 streams exceed cold water standard Gulf of Mexico - hypoxia Lake Winnipeg algae blooms Iowa Rivers drinking water

34 Total Nitrogen in Rivers Organic nitrogen Ammonium Ammonia Total Nitrate Nitrite

35 Nitrate is dominant form in high- nitrogen rivers 140 Total Nitrogen Load 20 Yr Avg Annual (Million lbs) organic N Ammonium-N Nitrite+Nitrate-N 0 Minnesota R. Jordan St. Croix R. Stillwater Miss. R. Anoka

36 Discussion areas Conditions Sources Trends Reductions

Stream nitrate concentrations (90 th Percentiles 2000-2010) Very low: <1 mg/l

37 Stream nitrate concentrations (90 th Percentiles ) Very low: <1 mg/l Low Medium: 3-5 mg/l High Exceeds 10 mg/l Conditions Sources Trends Reductions

38 Watershed nitrogen yields ( monitoring) Very low <2.3 lbs/ac/yr Low Medium High Highest 12+ lbs/ac/yr Conditions Sources Trends Reductions

39 SPARROW model nitrogen yield Very Low <1.4 lb/ac/yr 1/3 watersheds = 3/4 load to Mississippi Low Medium High Highest 12+ lb/ac/yr Conditions Sources Trends Reductions

40 Nitrogen Loads long-term average Conditions Sources Trends Reductions

41 Twin Cities region added 3.5% to river nitrogen load Conditions Sources Trends Reductions

42 Conditions Sources Trends Reductions

43 Nitrogen Sources Cropland groundwater Cropland tile drainage Cropland runoff Domestic wastewater Industrial wastewater Urban stormwater Septic systems Forests Atmospheric deposition Barnyard runoff Conditions Sources Trends Reductions

44 Cropland Groundwater Source Conditions Sources Trends Reductions

45 Cropland Tile Drainage Source Conditions Sources Trends Reductions

46 Statewide nitrogen sources to surface waters Urban Stormwater 1% Septic 2% Forests 7% Feedlot runoff <1% Atmospheric 9% Point sources 9% Cropland groundwater 30% Cropland runoff 5% Cropland tile drainage 37% Conditions Sources Trends Reductions

47 Nitrogen sources to surface waters Annual Nitrogen Load (million lbs) WW Point Sources Atmospheric Feedlot Runoff Septic Systems Urban Runoff Forest Cropland Runoff Tile Drainage Cropland Groundwater 10 0 Cedar River Des Moines River Lake Superior Lower Minnesota Mississippi River River Missouri River Conditions Sources Trends Reductions Rainy River Red River of the North St. Croix River Upper Mississippi River

48 Nitrogen source differences between basins Atmospheric Other NPS 3% 2% Forest 1% Crop Runoff 4% Point Sources 5% Minnesota River Cropland Groundwater 18% Other NPS 2% Forest 2% Atmospheric 2% Crop Runoff 9% Point Sources 5% Lower Mississippi Cropland Tile Drainage 67% Cropland Tile Drainage 23% Cropland Groundwater 57% Conditions Sources Trends Reductions

49 Comparing nitrogen loads 200 Dry year Annual TN Load (million lbs) River Monitoring Sum of Sources - Minnesota River Red River of the North St. Croix River Upper Mississippi River 200 Ave. year Annual TN Load (million lbs) Minnesota River Red River of the North St. Croix River Upper Mississippi River 200 Wet year Annual TN Load (million lbs) Minnesota River Red River of the North St. Croix River Upper Mississippi River Conditions Sources Trends Reductions

N source estimates similar to other findings Urban Stormwater 1% Point sources 9% Atmospheric 9% Septic 2% Forests 7% Feedlot runoff <1% Cropland groundwater 30% 1. Watershed monitoring 2.

50 N source estimates similar to other findings Urban Stormwater 1% Point sources 9% Atmospheric 9% Septic 2% Forests 7% Feedlot runoff <1% Cropland groundwater 30% 1. Watershed monitoring 2. Literature reviews Cropland runoff 5% 3. Statistical and non-statistical analyses Cropland tile drainage 37% 4. U.S. Geological Survey Model (SPARROW) 5. Modeling in Minnesota River Basin (HSPF) Conditions Sources Trends Reductions

51 Highest nitrate watersheds have the most row crops and tiling Conditions Sources Trends Reductions

52 Conditions Sources Trends Reductions

53 Mississippi River nitrate doubled or more since 1976 Increase Decrease No trend Conditions Sources Trends Reductions

54 Nitrate Concentrations Flow Adjusted Increase Decrease No trend to River Monitoring Sites 11 Decrease No trend Increase Recent Trends 52 River Monitoring Sites Decrease No trend Increase Conditions Sources Trends Reductions

55 Minnesota River nitrate high recent improvement Increase Decrease No trend Conditions Sources Trends Reductions

56 Conditions Sources Trends Reductions

57 Percent nitrogen reduction in treated area Riparian corn to perennials Marginal lands to perennials Crop crop (average) Cover crop (successful) Vegetative cover Extended rotations Wetlands Bioreactors Controlled drainage Tile water treatment Nitrification inhibitor Fert. timing & rate Reduced fert. Rates Fertilizer management Conditions Sources Trends Reductions

58 Percent N reduction to waters statewide Riparian corn to perennials Marginal lands to perennials Crop crop (average) Cover crop (successful) Extended rotations Wetlands Bioreactors Controlled drainage Nitrification inhibitor Fert. timing & rate Reduced fert. Rates Conditions Sources Trends Reductions

59 Reducing cropland nitrogen losses to surface waters statewide 35 % N Reduction (from cropland) Saving $77 Million Optimal fertilizer rate and timing $74 Million Saving $77 Million Fert. mgmt + tile drainage BMPs $1 Billion $74 Million Saving $77 Million Fert. mgmt + tile BMPs + vegetation BMPs Vegetation changes Tile drainage BMPs Fertilizer mgmt. optimized Cost estimates subject to change with fluctuating markets Conditions Sources Trends Reductions

60 Nitrogen reduction potential and costs vary by watershed $37 M [$4 M saved] Root River watershed $29 M $5 M [$2 M saved] LeSueur River watershed Vegetation changes Tile drainage BMPs Fertilizer mgmt optimized Conditions Sources Trends Reductions

61 Reducing nitrogen in wastewater discharges 9% of nitrogen load to rivers Can reduce by 35-65% Conditions Sources Trends Reductions

losses to rivers: 15-20% through fertilizer

62 Conclusions 1 High nitrate in Southern Minnesota cropland nitrate leaching to tile lines and groundwater 2 Concentrations increasing in Mississippi R since mid-1970 s Minnesota River high may be stabilizing/decreasing 3 Can reduce nitrogen losses to rivers: 15-20% through fertilizer mgmt + tile water treatment More vegetative cover needed for further reductions

63 Questions?

64 Sources to soils Note: Do not equate with sources to waters Conditions Sources Trends Reductions

65 Quantifying In-stream Biological Nitrogen Uptake Amy Hansen University of Minnesota

66 Eagle Creek: Ali Khosronejad, Kris Guentzel, Jessica Kozarek, Fotis Sotiropoulos, Miki Hondzo, Peter Wilcock, Dan Baker, Jacques Finlay Minnesota River: Jacques Finlay, Christy Dolph, Brent Dalzell Funding:

67 Synthesis of 3 studies: 1. Field sampling Le Seuer River basin 2. Analysis of long term monitoring data Minnesota River Basin 3. Reach scale injection experiment Eagle Creek, Savage MN

68 Motivation: nitrogen loading is high Robertson and Saad, 2011.

69 Excess nitrate has negative consequences

70 Motivation: nitrate is increasing Nitrate (mg/l) (Shakopee) Month Nitrate flux (kg/hr) Month Randall & Mulla 2001

71 Background N out : Denitrification N in : Upstream Run-off Groundwater N out : Downstream Groundwater Assimilation

72 1. When does nitrogen uptake occur? 2. Where does N uptake occur? 3. Is N uptake significant? 4. What is controlling the rate of N uptake?

73 Le Seuer River Basin: field sampling 100 sites including: tile outlets, ditches, streams, rivers, lakes, wetlands May Aug 2013

74 N uptake at a reach scale date hydrologic storage? change in TDN (mg/l) % change in TDN 8/13/2013 lake % 6/12/2013 lake % 8/15/2013 no % 8/13/2013 no % 8/13/2013 no % 6/12/2013 no % 6/12/2013 no % 6/12/2013 no % 6/12/2013 no % 8/15/2013 no % 7/24/2013 wetland % 7/24/2013 wetland % 6/11/2013 wetland % -negative sign indicates downstream reduction in concentration

75 Field sampling: across wetlands and lakes Wetlands Percent N reduction: 73 93% Reduction in N concentration: 16-23mg/L June - August Lakes Percent N reduction: 77 93% Reduction in N concentration: 7-11 mg/l June - August

76 Field sampling: wetland complex 5.3 mg/l

77 35 30 Dissolved organic carbon Total dissolved nitrogen DOC or TDN (mg L -1 ) Proportion wetland cover

78 Influence of carbon on denitrification rates 250 Unamended Soil den rate (mg/m2/hr) FB Lk out(n limited?) DOC (mg/l)

79 Minnesota River Basin: monitoring data mass balance Data selection criteria: Date matched Less than 10% change in discharge Lateral flow outward Where: MN River Maple River Le Seuer River

80 Mass balance from monitoring data C US Q US C LAT Q LAT C DS Q DS (mass out) = (mass in) (biological uptake) C DS Q DS + C LAT Q LAT = C US Q US -B

81 Le Seuer River: St. Clair to Rapidan (~16.8 km) Maple River: Sterling Center to Rapidan (~14.5km) Fraction removed Le Seuer River: Month Fraction N removed Maple River: Month

82 Minnesota River: St Peter - Henderson 100 % nitrate removed 50 0 Aug-76 Aug-86 Aug-96 Aug-06 Henderson St Peter

additions Conservative and reactive tracers Time series (dc/dt) Quantifying

83 Eagle Creek Minnesota River basin, urban Spring fed, shady, natural trout stream Sand and gravel, large woody debris present 130 m reach Tracer additions Conservative and reactive tracers Time series (dc/dt) Quantifying uptake 1-D transport model with transient storage 3-D Navier stokes solution with LES closure

84 Reactive tracer, continuous release 1-D model with advection, dispersion, reaction and storage (OTIS from USGS) 1.5 NO3-N (mg/l) Time (hrs) 30% of nitrate mass removed within reach following Runkel (2007): 39% nitrate uptake occurring in main channel 61% nitrate uptake occurring in transient storage

85 Conservation tracer CFD simulation 3D solution to Navier Stokes equations for measured topography and substrate roughness with large eddy simulation closure scheme for subgrid scales Additional data: High resolution topographic mapping Substrate characterization

86 Is in-stream biological nitrate uptake significant? From field sampling % removal within wetlands and lakes Wetlands: biological uptake rate: 21 kg/hr/km 2 (approx area) Lakes: biological uptake rate: 2.75 kg/hr/km 2 (Freeborn Lake) Measured denitrification rates up to 200 kg/hr/km 2 From mass balance on monitoring data: 0-80 % removal within ~20 km reach Biological uptake rate: 0 60 kg/hr (per reach) High temporal variability! From Eagle Creek enrichment experiment: 30% of nitrate mass removed (130m reach) Biological uptake rate: 1.24 kg/hr/km (~300 kg/hr/km 2 ) High sub-reach spatial heterogeneity Need to normalize by area to compare!

87 Conclusions Surprisingly high springtime nitrate uptake rates Large reductions in nitrate concentrations across wetlands and lakes and transient storage (consistent with other studies) Potentially carbon limited denitrification at many sites Biological nitrate uptake could be enhanced through increased carbon supply and additional storage

88 Thank you. Questions? Contact information: Amy Hansen, References: OTIS: Clarke, 1924 The composition of the River and lake waters of the United States, USGS Professional paper 135 Randall GW and Mulla DJ, 2001, Nitrate nitrogen in surface waters as influenced by climatic conditions and agricultural practices, Journal of Enivronmental Quality30:2, Runkel RL, Toward a transport-based analysis of nutrient spiraling and uptake in streams, LIMNOLOGY AND OCEANOGRAPHY-METHODS Volume: 5 Pages: Robertson, D.M. and D.A. Saad, Nutrient Inputs to the Laurentian Great Lakes by Source and Watershed Estimated Using SPARROW Watershed Models. Journal of the American Water Resources Association (JAWRA) 47(5): DOI: /j x

90 Maple River: Fraction N removed Month Uptake rate (kg/hr/km) Maple River: Month 0.9 Le Seuer River: Le Seuer River: Fraction removed Month Uptake rate (kg/hr/km) Month

Nitrate, Well Testing and Rules

Nitrate, Well Testing and Rules Where is all this heading? February 7, 2017 Pesticide and Fertilizer Management Division Minnesota Department of Agriculture Outline Nitrogen Fertilizer Management Plan