Nitrogen (N) is one of the most widely distributed elements in nature and is present virtually everywhere on the earth’s crust in one or more of its many chemical forms. Nitrate (NO3), a mobile form of N, is commonly found in ground and surface waters throughout the country. Nitrate is generally the dominant form of N where total N levels are elevated. Nitrate and other forms of N in water can be from natural sources, but when N concentrations are elevated, the sources are typically associated with human activities (Dubrovski et al., 2010). Concerns about nitrate and total N in Minnesota’s water resources have been increasing due to effects of nitrate on certain aquatic life and drinking water supplies, along with increasing N in the Mississippi River and its impact on Gulf of Mexico oxygen depletion.
Where does nitrate come from?
Source: Nitrogen in Minnesota Surface Waters (2013)
How does nitrate move from cropland into our water?
Source: Nitrogen in Minnesota Surface Waters (2013) |
Tile drainage pathway |
Where does the nitrate go?
Nitrate loads leaving Minnesota via the Mississippi River contribute to the oxygen-depleted “dead zone” in the Gulf of Mexico (currently estimated to be the size of Massachusetts). The dead zone cannot support aquatic life, affecting commercial and recreational fishing and the overall health of the Gulf.
How do we reduce the nitrate going into surface waters?
Tactics for reducing cropland nitrate going into surface waters fall into three categories:
Nitrate fertilizer efficiency has improved during the past two decades. While further refinements in fertilizer rates and application timing can be expected to reduce nitrate loads by roughly 13% statewide, additional and more costly practices will also be needed to make further reductions and meet downstream needs. Statewide reductions of more than 30% are not realistic with current practices.
To see progress, nitrate leaching reductions are needed across large parts of southern Minnesota, particularly on tile-drained fields and row crops over thin or sandy soils. Only collective incremental changes by many over broad acreages will result in significant nitrogen reductions to downstream waters.
Nitrogen is considered a limiting nutrient in the Gulf of Mexico, the body of water where much of Minnesota’s river and stream waters ultimately discharge. When nutrients in the Mississippi River originating in 31 states reach the Gulf of Mexico, a low oxygen “dead zone” known as hypoxia develops.
Hypoxia, which means low oxygen, occurs when excess nutrients, primarily N and P, stimulate algal growth in the Mississippi River and gulf waters. The algae and associated zooplankton grow well beyond the natural capacity of predators or consumers to maintain the plankton at a more balanced level. As the short-lived plankton die and sink to deeper waters, bacteria decompose the phytoplankton carbon, consuming considerable oxygen in the process. Water oxygen levels plummet, forcing mobile creatures like fish, shrimp, and crab to move out of the area. Less mobile aquatic life become stressed and/or dies.
The freshwater Mississippi River is less dense and warmer compared to the more dense cooler saline waters of the gulf. This results in a stratification of the incoming river waters and the existing gulf waters, preventing the mixing of the oxygen-rich surface water with oxygen-poor water on the bottom. Without mixing, oxygen in the bottom water is limited and the hypoxic zone remains. Hypoxia can persist for several months until there is strong mixing of the ocean waters, which can come from a hurricane or cold fronts in the fall and winter.
Hypoxic waters have dissolved oxygen concentrations of less than about 2-3 mg/l. Fish and shrimp species normally present on the ocean floor are not found when dissolved oxygen levels reduce to less than 2 mg/l. The Gulf of Mexico hypoxic zone is the largest in the United States and the second largest in the world. The maximum areal extent of this hypoxic zone was measured at 8,500 square miles during the summer of 2002. The average size of the hypoxic zone in the northern Gulf of Mexico in recent years (between 2004 and 2008) has been about 6,500 square miles, the size of Lake Ontario.
Hypoxia Task Force
A multi-state Hypoxia Task Force (which includes Minnesota) released their first Action Plan in 2001. This plan was reaffirmed and updated in a 2008 Action Plan. The Hypoxia Task Force established a collaborative interim goal to reduce the 5-year running average areal extent of the Gulf of Mexico hypoxic zone to less than 5,000 square kilometers (1,931 square miles). Further information about Gulf of Mexico hypoxia can be found at: https://gulfhypoxia.net/
A thorough technical discussion of the research associated with Gulf of Mexico hypoxia and possible nutrient reduction options is presented by the US EPA (2007). The report notes that P may be more influential than N in the near-shore gulf water algae growth, particularly in the spring months, when algae and phytoplankton growth are often greatest. In the transition months between spring and summer, the algae and phytoplankton growth are controlled largely by the coupling of P and N. Nitrogen typically becomes the controlling nutrient in the summer and fall months. Based on these more recent findings, emphasis has shifted to developing strategies for dual nutrient removal (P and N). The Science Advisory Board recommends a 45% reduction in riverine TP and TN loads into the Gulf of Mexico (US EPA 2007).
Minnesota’s Contribution to Gulf Hypoxia
Certain areas of Minnesota release large quantities of N and P to Minnesota streams. Much of the nutrients remain in the Mississippi River system, ultimately reaching the Gulf of Mexico. Alexander et al. (2008) used computer modeling (SPARROW) to estimate the proportion of gulf nutrients originating in different geographic areas. The model accounted for the loss of nutrients in the river, river pools, and backwaters prior to reaching the Gulf of Mexico. This modeling indicated that Minnesota contributed 3% of Gulf of Mexico N and 2% of the P. However, with more recent SPARROW modeling, Minnesota’s contribution is estimated to be higher, ranking as the sixth highest state for N contributions behind Iowa, Illinois, Indiana, Ohio, and Missouri. The more recent modeling estimates indicate that Minnesota is responsible for about 6% of the N loading and 4% of the P loading into the Gulf of Mexico (Robertson, 2012 personal communication).
Recognizing that it will take a concerted effort by all states which contribute significant amounts of nutrients to the gulf, the MPCA agreed with other top nutrient contributing states to complete and implement a comprehensive N and P reduction strategy. This plan was completed in 2014 (Mississippi River/Gulf of Mexico Watershed Nutrient Task Force, 2008). The goal of the Action Plan is to reduce nutrients to the Gulf of Mexico while at the same time addressing in-state water protection and restoration.
Minnesota Nitrogen Study
The MPCA conducted a study of nitrogen in surface waters so that we can better understand the nitrogen conditions in Minnesota’s surface waters, along with the sources, pathways, trends and potential ways to reduce nitrogen in waters.
Excerpts from Nitrogen in Minnesota Surface Waters
Sources of Nitrogen - Results Overview
Sources of Nitrogen - Wastewater Point Source Nitrogen Loads
Sources of Nitrogen - Atmospheric Deposition of Nitrogen in Minnesota Watersheds
Statewide - N Sources to Waters - Average Year
Source: Nitrogen in Minnesota Surface Waters, Sources of Nitrogen - Results Overview (2013)
Cropland sources contribute an estimated 73 percent of the statewide N load during an average precipitation year. Cropland nitrogen is primarily delivered to surface waters through subsurface pathways of tile drainage and groundwater.
Upper Mississippi River Basin - N Sources to Waters - Average Year
Source: Nitrogen in Minnesota Surface Waters, Sources of Nitrogen - Results Overview (2013)
Statewide - N Sources to Surface Waters Chart -Average Year
Source: Nitrogen in Minnesota Surface Waters, Sources of Nitrogen - Results Overview (2013)
Estimated N loads to surface waters from different sources within the Minnesota portions of major basins during an average precipitation year. “Ag” represents cropland sources.
Watershed Pollutant Load Monitoring Network - MPCA
Water Quality Databases
DNR/MPCA Cooperative Stream Gaging Network – USGS, DNR, MPCA – Stream discharge and links to Division of Waters Resources, climate information, river levels, water quality information, recreation and commonly used hydrologic terms
USGS – USGS discharge Information
EDA Environmental Data Access – Water quality data collected for all MPCA monitoring projects
EQuIS – Environmental Quality Information System – Water quality data from more than 17,000 sampling locations across the state.
Maps From: Watershed Pollutant Load Monitoring Network - MPCA
|
Source: Watershed Pollutant Load Monitoring Network - MPCA (2014)
Average annual flow-weighted mean concentrations for Total Nitrogen near watershed outlets. One to three year averages derived from available information collected in 2007-11.
|
Source: Watershed Pollutant Load Monitoring Network - MPCA (2014)
Average annual yield (lbs/acre) for Total Nitrogen near watershed outlets. One to three year averages derived from available information collected in 2007-11.
|
Source: Watershed Pollutant Load Monitoring Network - MPCA (2014)
Average annual Total Nitrogen Load near watershed outlets. One to three year averages derived from available information collected in 2007-11.
Excerpts from Nitrogen in Minnesota Surface Waters - MPCA
Chapter 4: Modeled Nitrogen Loads (SPARROW)
The MPCA’s Nitrogen Study shows elevated nitrate levels, particularly in the southern third of Minnesota.
Source: Nitrogen in Minnesota Surface Waters, Chapter 4: Modeled Nitrogen Loads (SPARROW) (2013)
Data Source: SPARROW flow-weighted mean TN concentration by HUC8 watersheds. The value represents the median FWMC of all subwatershed catchments within the HUC8 watersheds.
SPARROW Modeling for the Leech Lake River Watershed indicated average flow-weighted mean TN concentration of 0.84 mg/l. This value represents the median FWMC of all subwatershed catchments within the Leech Lake River Watershed.
Source: Nitrogen in Minnesota Surface Waters, Chapter 4: Modeled Nitrogen Loads (SPARROW) (2013)
SPARROW model annual TN yield results by HUC8 watershed in lbs/acre/year. The basin yields represent the total load delivered to the watershed outlet or state border divided by the sum of the SPARROW (MRB3 2002) catchment area.
SPARROW model annual TN yield results for the Leech Lake River Watershed was 0.22 lbs/acre/year.
Statewide Comparison of Nitrate+Nitrate-N Yields (lbs/ac)
|
Nitrite+Nitrate-N |
S. Central |
11-19 |
Southeast |
8-9 |
Southwest |
4-9 |
Central |
1-2 |
Northwest |
0.1-1 |
Northeast |
0.1-2 |
Source: Nitrogen in Minnesota Surface Waters (2013)
Total Nitrogen Contributions to the Mississippi River (percent Load by HUC8 Watershed)
Source: Nitrogen in Minnesota Surface Waters (2013)
Percent contribution of TN delivered to the Mississippi River in Keokuk, Iowa, from each of Minnesota’s HUC8 Watersheds which ultimately drain into the Mississippi River. Each bar represents the percent TN originating from a single watershed, from highest contributor (left) to lowest contributor (right).
Fifteen of the 45 watersheds draining into the Mississippi River from Minnesota each contribute over 3 percent of the modeled load delivered to the Mississippi River in southern Iowa (Keokuk). Combined, these 15 watersheds contribute 73.7 percent of the total nitrogen load delivered to Keokuk from Minnesota. These higher loading watersheds are mostly located in South-central and southeastern Minnesota. The other thirty watersheds each contribute between 0 and 2.4 percent of the load, and are thus considered relatively minor contributors.
WS # |
Watershed Name |
% load contribution |
33 |
Lower Minnesota River |
7.3 |
28 |
Minnesota River - Mankato |
6.7 |
30 |
Blue Earth River |
6.4 |
32 |
Le Sueur River |
5.7 |
25 |
Minnesota River - Yellow Medicine River |
5.6 |
39 |
Cannon River |
5.2 |
43 |
Root River |
5.2 |
41 |
Zumbro River |
4.9 |
19 |
South Fork Crow River |
4.7 |
48 |
Cedar River |
4.4 |
29 |
Cottonwood River |
4.3 |
20 |
Mississippi River - Twin Cities |
3.7 |
31 |
Watonwan River |
3.4 |
51 |
Des Moines River - Headwaters |
3.2 |
26 |
Chippewa River |
3.1 |
18 |
North Fork Crow River |
2.4 |
16 |
Sauk River |
1.7 |
27 |
Redwood River |
1.6 |
40 |
Mississippi River - Winona |
1.5 |
15 |
Mississippi River - Sartell |
1.4 |
38 |
Mississippi River - Lake Pepin |
1.4 |
17 |
Mississippi River - St. Cloud |
1.4 |
21 |
Rum River |
1.3 |
49 |
Shell Rock River |
1.3 |
10 |
Mississippi River - Brainerd |
1.2 |
37 |
Lower St. Croix River |
1.1 |
24 |
Lac Qui Parle River |
1.1 |
23 |
Pomme de Terre River |
1.0 |
50 |
Winnebago River |
0.8 |
36 |
Snake River |
0.8 |
9 |
Mississippi River - Grand Rapids |
0.7 |
12 |
Crow Wing River |
0.7 |
46 |
Upper Iowa River |
0.6 |
13 |
Redeye River |
0.6 |
35 |
Kettle River |
0.6 |
14 |
Long Prairie River |
0.6 |
53 |
East Fork Des Moines River |
0.5 |
22 |
Minnesota River - Headwaters |
0.4 |
44 |
Mississippi River - Reno |
0.4 |
42 |
Mississippi River - La Crescent |
0.4 |
34 |
Upper St. Croix River |
0.3 |
52 |
Lower Des Moines River |
0.2 |
7 |
Mississippi River - Headwaters |
0.1 |
11 |
Pine River |
0.1 |
8 |
Leech Lake River |
0.0 |
47 |
Upper Wapsipinicon River |
0.0 |
Source: Nitrogen in Minnesota Surface Waters (2013)
Excerpts from Nitrogen in Minnesota Surface Waters
Nitrate Trends in Minnesota Rivers
Nitrogen Trend Results from Previous Studies
Nitrate Trends in the Upper Mississippi River main stem (Blackberry to Fridley)
Many tributaries flow into the Upper Mississippi River. Trends in all tributaries, along with trends in point source discharges and groundwater base flow discharging directly into the Mississippi River, affect the Mississippi River trends. Trends in four major tributaries were analyzed for this study. Three of the four tributaries showed an overall increase since 1976 and one tributary (Crow River) had no trend (Table 3). The nature of the increases was different in all three tributaries, with different magnitudes of increases (from 15 to 256%) and different periods of time when these increases occurred. During the past decade, the Long Prairie and Crow Rivers had no trend, while nitrate concentrations increased in the Sauk River and decreased in the Rum River.
The Sauk River is the only analyzed tributary that had a continuously upward trend in the past two decades, as was also found in the Mississippi River at Sauk Rapids, Monticello, Anoka, and Fridley. We were not able to assess the trend results in the many other tributaries to the upper Mississippi River due to a lack of sufficient monitoring data, and it is possible that those other tributaries also contributed to the upward trends in the Mississippi River.
Source: Nitrogen in Minnesota Surface Waters, Nitrate Trends in the Minnesota River Basin (2013)
Phosphorus is the nutrient primarily responsible for the eutrophication (nutrient enrichment of waterbodies) of Minnesota’s surface waters. Phosphorus is an essential nutrient for plants, animals and humans. It is one of the 20 most abundant elements in the solar system, and the 11th most abundant in the earth’s crust. Under natural conditions phosphorus (P) is typically scarce in water. Human activities, however, have resulted in excessive loading of phosphorus into many freshwater systems. This can cause water pollution by promoting excessive algae growth, particularly in lakes. Lakes that appear relatively clear in spring can resemble green soup in late summer due to algae blooms fueled by phosphorus. Water quality can be further impaired when bacteria consume dead algae and use up dissolved oxygen,suffocating fish and other aquatic life.
An overabundance of phosphorus—specifically usable (bioavailable) phosphorus—results in excessive algal production in Minnesota waters. Phosphorus from point sources may be more bioavailable, impacting surface water quality more than a similar amount of nonpoint source phosphorus that enters the same surface water conditions. Total phosphorus levels of 100 or more ppb categorize lakes as highly eutrophic, with high nutrient and algae levels.
In some water bodies, the concentration of phosphorus is low enough to limit the growth of algae and/or aquatic plants. In this case, scientists say phosphorus is the limiting nutrient. For example, in water bodies having total phosphorus concentrations less than 10 parts per billion (1 ppb – equal to one drop in a railroad tank car), waters will be nutrient-poor and will not support large quantities of algae and aquatic plants.
MPCA
Phosphorus contributions to Minnesota surface waters by point and nonpoint sources are known to vary, both geographically and over time, in response to annual variations in weather and climate. Nonpoint sources of phosphorus tend to comprise a larger fraction of the aggregate phosphorus load to Minnesota surface waters during relatively wet periods, while point sources become increasingly important during dry periods.
Minnesota River Basin-Lake Pepin
Three major river basins empty into Lake Pepin in southeastern Minnesota – St. Croix, Upper Mississippi, and the Minnesota. Lake Pepin is listed as an impaired water due to sediment and eutrophication (excessive nutrients and algae). The Minnesota River contributes a majority of the sediment. In a highly turbid water body such as the Minnesota River, much of the phosphorus load is attached to eroded soil particles, especially at higher flows. Much of the particulate phosphorus in the Minnesota River converts to the soluble that can become available to algae. This occurs in several ways: chemical and physical change (diagenesis) of sediment in the river or lake bed, interaction with dissolved chemicals in the water, and decay of organic P releasing dissolved phosphorus from soil particles. Models being used in the Lake Pepin and Minnesota River Total Maximum Daily Load projects keep track of both particulate and dissolved forms of phosphorus.
New Water Quality Standards for River Eutrophication
The Minnesota Pollution Control Agency is currently developing new water quality standards for River Eutrophication and Total Suspended Solids. Visit the MPCA website for more information.
Sources:
Minnesota Nutrient Reduction Strategy - MPCA
Phosphorus: Sources, Forms, Impacts on Water Quality - MPCA
New Water Quality Standards for River Eutrophication and Total Suspended Solids - MPCA
Statewide Phosphorus Sources, Average Year
Source: Minnesota Nutrient Reduction Strategy, Chapter 5 Point and Nonpoint Source Reductions (2013)
Under normal water flows, roughly two- thirds of the total phosphorus load to lakes and rivers comes from nonpoint sources such as runoff from pasture and croplands, atmospheric deposition and stream bank erosion. Phosphorus loading contributed by runoff from pastures and croplands is largest source of nonpoint phosphorus on a statewide basis. Other nonpoint sources include urban runoff, non-agricultural rural runoff and seepage from individual sewage treatment systems.
Approximately 30 percent of the phosphorus load to Minnesota waters comes from point sources such as municipal and industrial wastewater treatment facilities. The magnitude of various sources of phosphorus varies greatly throughout the state due to the diverse nature of Minnesota’s watersheds.
Mississippi River
Phosphorus Sources to Surface Waters
Current: Average Precipitation Year
Source: Minnesota Nutrient Reduction Strategy (2013)
Pollutant Load Monitoring Sites in Minnesota
Watershed Pollutant Load Monitoring Network - MPCA
Water Quality Databases
DNR/MPCA Cooperative Stream Gaging Network – USGS, DNR, MPCA – Stream discharge and links to Division of Waters Resources, climate information, river levels, water quality information, recreation and commonly used hydrologic terms
USGS – USGS discharge Information
EDA Environmental Data Access – Water quality data collected for all MPCA monitoring projects
EQuIS – Environmental Quality Information System – Water quality data from more than 17,000 sampling locations across the state.
Source: Watershed Pollutant Load Monitoring Network - MPCA (2014)
Average annual flow-weighted mean concentrations (mg/L) for Total Phosphorus near watershed outlets. One to three year averages derived from available information collected in 2007-11.
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Source: Watershed Pollutant Load Monitoring Network - MPCA (2014)
Average annual Total Phosphorus Yield (lbs/acre) near watershed outlets based on yearly averages derived from available information collected in 2007-11.
|
Source: Watershed Pollutant Load Monitoring Network - MPCA (2014)
Average annual Total Phosphorus Load (kg) near watershed outlets based on yearly averages derived from available information collected in 2007-011.
SPARROW modeling
The Spatially Referenced Regressions on Watershed attributes (SPARROW) model, developed and maintained by the United States Geological Survey (USGS), was used for this study to estimate Total Phosphorus (TP) loads, yields, and flow-weighted mean concentrations (FWMC) in Minnesota 8-digit Hydrologic Unit Code (HUC8) watersheds and major basins.
Modeling Total Phosphorus Yield (lb/ac/yr)
Source: Minnesota Nutrient Reduction Strategy (2013)
Data Source: SPARROW flow-weighted mean TP concentration by HUC8 watersheds. The value represents the median FWMC of all subwatershed catchments within the HUC8 watersheds.
SPARROW Modeling for the Leech Lake River Watershed indicated average flow-weighted mean TP concentration of 0.02 mg/l. This value represents the median FWMC of all subwatershed catchments within the Leech Lake River Watershed FWMC.
Source: Minnesota Nutrient Reduction Strategy (2013)
Statewide
Implementation of MPCA’s Phosphorus Strategy and Minnesota Rule Chapter 7053.0255 has resulted in significant wastewater effluent phosphorus load reductions since the year 2000.
Statewide Wastewater Phosphorus Effluent Loading
Source: Minnesota Nutrient Reduction Strategy, Chapter 5: Point and Nonpoint Source Reductions
Municipal and Industrial Wastewater Phosphorus Trends & Projections
Source: Minnesota Nutrient Reduction Strategy, Chapter 4: Management Priorites and Recent Progress
Summary of Recent Progress in Phosphorus Source Loads by Major Basin
Efforts between 2000 and present have resulted in significant progress in reducing phosphorus loads in the Mississippi River Basin, due to both agricultural BMPs and wastewater treatment plant upgrades.
Source: Minnesota Nutrient Reduction Strategy, Chapter 4: Management Priorites and Recent Progress
Notes: Recent progress is the percent of baseline load remaining after accounting for reductions since 2000.
Source: Minnesota Nutrient Reduction Strategy, Appendix A
Assessed Lakes (2012) in the Leech Lake River Watershed
Impairment Parameters:
Nutrients = Nutrients
HgF = Mercury in Fish Tissue
HgW = Mercury in Water Column
CL = Chloride
PCBF = PCBs in Fish
PFOS = Perfluorooctane Sulfonate (PFOS) in Fish Tissue
Affected Uses:
AQC = Aquatic Consumption
AQR = Aquatic Recreation
AQL = Aquatic Life
Source: Minnesota Pollution Control Agency Assessed Waters (2012) & Impaired Waters (2012)
Statewide Impaired Lakesheds
Source: Minnesota Nutrient Reduction Strategy, Chapter 2 Setting Goals and Milestones (2013)
For more information about what you can do to protect area lakes, visit MPCA's Lake protection and management website.
Watershed Contacts - MPCA
Local Government Units and Partner Agencies - BWSR
Watershed Group
Leech Lake Area Watershed Foundation
(218)675-5773
info@leechlakewatershed.org
MPCA Watershed Contact
Phil Votruba, Pollution Control Specialist Senior
Brainerd Office
(218)316-3901
phil.votruba@state.mn.us
Beltrami County
Beltrami County
Beltrami County SWCD
Cass County
Cass County
Cass County SWCD
Hubbard County
Hubbard County
Hubbard County SWCD
The Minnesota Nutrient Reduction Strategy - MPCA
Driving forces and building blocks for the Nutrient Reduction Strategy
Hypoxia Action Plan
Clean Water Land & Legacy Amendment
Minnesota Watershed Approach
Groundwater Proection and Nitrogen Fertilizer Management Plan
Minnesota Water Sustainability Framework
Detailed Assessment of Phosphorus Sources to Minnesota Watersheds
Nitrogen in Minnesota Surface Waters
Modeled Nitrogen Loads (SPARROW)
Watershed Pollutant Load Monitoring - MPCA
Long Term Water Quality Monitoring - USGS, Met Council, Manitoba
Upper Mississippi River Basin
Big Sandy Area Lakes TMDL Project – Excess Nutrients (MPCA)
Effects of Reducing Nutrient Loads to Surface Waters within the Mississippi River Basin and the Gulf of Mexico (1999)
Historical Changes in Sediment and Phosphorus Loading to the Upper Mississippi River: Mass-Balance Reconstructions from the Sediments of Lake Pepin (2000)
Historical changes in sediment and phosphorus loading to the upper Mississippi River: mass-balance reconstructions from the sediments of Lake Pepin (2009)
Winter Rye Best Management Practices to Reduce Loads of Sediment and Nutrients to Minnesota Surface Water (2009-2013)
Nitrogen and phosphorus in the Upper Mississippi River: Transport, processing and effects on the river ecosystem (2010)
Characterizing nitrates in private drinking water wells-central sands region (2010-2016)
Irrigation Workshops and the on Farm Nitrogen Management Program in Central Minnesota (2010-2018)
HSPF Model Framework Development for the Sauk River, Crow River, and South Fork Crow River (2011)
HSPF Watershed Modeling Phase III for the Sauk River, Crow River (North Fork Crow River, and South Fork River) (2011-2012)
Villa Park Wetland Restoration Project (2013-2014)
Sauk and Crow Rivers Lake Internal P Loadings, Scenarios, and GenScn Project Development (2012)
Prioritizing Conservation Implementation in the Mississippi Headwaters (2012-2014)
HSPF Modeling of the Upper Mississippi Mainstem and Rum Rivers (2013)
CROW Joint Power Board
Citizen Stream Monitoring CSMP Results Archive
JPB Completed Water Quality Improvement Projects
North Fork Crow River Watershed Restoration & Protection Project
North Fork TMDL Project
South Fork Crow River Watershed Restoration & Protection Project
Crow River Diagnostic Study Report Summary (2005)
Elk River Watershed Association
ERWA Projects
ERWA Reports & Publications
Elk River Watershed Pollution Reduction (2011-2013)
Leech Lake River Watershed
Watershed Restoration and Protection (MPCA)
Leech Lake River Major Watershed WRAP Strategy (MPCA)
Rapid Watershed Assessment: Leech Lake (NRCS)
Leech Lake Area Watershed Foundation
LLAWF Land Conservation Options
Beltrami County
County Environmental Services
SWCD Projects
SWCD Reports
SWCD Services
Beltrami County Comprehensive Local Water Management Plan 2008-2013
SSTS Imminent Health Threat Abatement Grant Program 2011-2012
SSTS Program Enhancement Grant Program 2011-2013
Cass County
County Environmental Services
SWCD Plans & Reports
SWCD Projects
Cass County Comprehensive Local Water Management Plan 2009-2014
SSTS Program Enhancement Grant Program 2010-2011 2011-2013
SSTS Imminent Health Threat Abatement Grant Program 2010-2011 2012-2014
Cass County Water Quality Enhancement and Shoreline Protection (2011-2012)
Shallow Lake Shoreland Protection: Wild Rice Lakes (2011-2014)
Cost Effective Stormwater Control in Cass County (2013-2015)
Hubbard County
County Environmental Service
SWCD Programs
SWCD Reports
Hubbard County Local Water Management Plan 2007-2012
Shallow Lake Shoreland Protection: Wild Rice Lakes (2011-2014)
Leech Lake River Watershed
Percent of County in Watershed
Water Plan Links
Beltrami County LWMP 2008-2013
Cass County LWMP 2009-2014
Hubbard County LWMP 2007-2012
Local Water Management Overview
County Comprehensive Local Water Management - BWSR
Minnesota Nutrient Strategy Overview
Nitrogen Science
Strategies for Nutrient Reduction - Wastewater
Planning Tools
Minnesota Watershed Nitrogen Reduction Planning Tool - Nitrogen BMP Spreadsheet (Lazarus et al., 2013)
Nitrogen Priority Watersheds & Reduction Milestone
The Minnesota Nutrient Reduction Strategy - MPCA
Excerpts from Chapter 4: Management Priorities and Recent Projects
Nitrogen Priority Watersheds |
Reduction Milestone |
Source: The Minnesota Nutrient Reduction Strategy , Chapter 4: Management Priorities and Recent Projects (2013)
Priority Sources
Priority sources are determined on a basin scale, although it should be noted that different sources may be more or less important at the local scale. Priority sources at the HUC8 scale or smaller will be determined through watershed planning efforts at that scale.
Source: The Minnesota Nutrient Reduction Strategy , Chapter 4: Management Priorities and Recent Projects (2013)
Example BMP Scenario for Nitrogen Reduction
The Minnesota Nutrient Reduction Strategy - MPCA
Excerpts from Chapter 5: Point and Nonpoint Source Reductions
Source: The Minnesota Nutrient Reduction Strategy , Chapter 4: Management Priorities and Recent Projects (2013)
See "Economics" Tab for a Watershed BMP Nitrogen Reduction Scenario.
Minnesota Nutrient Strategy Overview
Phosphorus Science
Strategies for Nutrient Reduction - Wastewater
Phosphorus Priority Watersheds & Reduction Milestone
The Minnesota Nutrient Reduction Strategy - MPCA
Excerpts from Chapter 4: Management Priorities and Recent Projects
Phosphorus Priority Watersheds |
Source: The Minnesota Nutrient Reduction Strategy (2013)
Priority Sources
Priority sources are determined on a basin scale, although it should be noted that different sources may be more or less important at the local scale. Priority sources at the HUC8 scale or smaller will be determined through watershed planning efforts at that scale.
Source: The Minnesota Nutrient Reduction Strategy , Chapter 4: Management Priorities and Recent Projects (2013)
Agricultural BMPs
Example BMP scenario for Phosphorus Reduction
The Minnesota Nutrient Reduction Strategy - MPCA
Excerpts from Chapter 5: Point and Nonpoint Source Reductions
Source: The Minnesota Nutrient Reduction Strategy, Chapter 5: Point and Nonpoint Source Reductions (2013)
Watershed Summary
Rapid Watershed Assessment Resource Profile: Leech Lake - NRCS
Lake Pepin Legacy Alliance - County Scorecard
Upper Mississippi River Basin - MPCA
Conservation Practices
Minnesota Agricultural Water Quality Certificate Program - Sauk River Pilot - MDA
Conservation Marketplace of Minnesota - Ecosystem Services Market
Discovery Farms Minnesota - Core Farm
Conservation Easements - BWSR
Conservation Implementation - BWSR
Interactive Conservation Easement Map RIM - BWSR
Conservation Practices - MDA
BMP Summary
Excerpts from The Minnesota Nutrient Reduction Strategy - MPCA
Chapter 5 - Point and Nonpoint Source Reductions
Appendix C - Agricultural BMPs
Because agricultural sources contribute the bulk of the statewide nitrogen load and a substantial portion of the phosphorus load, nitrogen and phosphorus reductions from agricultural sources are key to successfully achieving the milestones. Recommended agricultural BMPs and strategy options for promoting adoption of the BMPs to address phosphorus and nitrogen are provided in the links above.
Phosphorus: Based on the SPARROW model and the source attributions developed in the Detailed Assessment of Phosphorus Sources to Minnesota Watersheds (Barr Engineering 2004), agricultural sources contribute an estimated 38 percent of the statewide phosphorus load. A large part of the remaining phosphorus load is due to stream channel erosion, much of which is indirectly affected by agricultural runoff and intensive drainage practices (Schottler et al. 2013).
Nitrogen: Based on the Nitrogen in Minnesota Surface Waters study (MPCA 2013), agriculture contributes 73 percent of the statewide nitrogen load in a typical year.
See "Strategy - N Reduction" and "Strategy - P Reduction" Tabs for example BMP Scenarios for Nitrogen and Phosphorus Reduction.
Minnesota Watershed Nitrogen Reduction Planning Tool - Nitrogen BMP Spreadsheet (Lazarus et al., 2013)
Minnesota Nutrient Reduction Strategy SPARROW - (MPCA, 2013)
Lake Pepin Watershed Full Cost Accounting SWAT, InVEST, Sediment Rating Curve Regression, and Optimization (Dalzell et al., 2012)
GSSHA Model – Agricultural Water Certification Program – GSSHA Model – (MDNR, In Progress)
USDA-NRCS Nutrient Tracking Tool – Tarleton State (Texas Example)
NTT estimates the nutrient and sediment load leaving a farm field through surface water runoff and leaching below the rooting zone and can be used to quantify the water quality benefits of different agricultural management systems and conservation practices. Designed and developed by the USDA Natural Resources Conservation Service (NRCS), USDA Agricultural Research Service (ARS), and Texas Institute for Applied Environmental Research at Tarleton State University (TiAER), NTT is intended for use by agricultural professionals or others familiar with farm procedures and conservation practices.
Ag BMP Assessment and Tracking Tool – Houston Engineering
Solutions for improving impaired waters often rely on the use of agricultural best management practices (BMPs). The goal of this project is to collect and disseminate thorough and accurate information on the use and effectiveness of agricultural BMPs in the State of Minnesota. Stakeholders can use this information to inform, mock-up and track their BMP implementation strategies.
AG BMP Database - Houston Engineering
The goal of the Ag BMP Database is to provide a comprehensive source of information on the application and effectiveness of agricultural BMPs within the State of Minnesota. The database was developed to hold information on BMPs that are commonly used in the State to address water quality impairments for: sediment, nitrogen, phosphorus, and bacteria.
Ecological Ranking Tools
Watershed Health Assessment Framework - MDNR
The Watershed Health Assessment Framework (WHAF) provides a comprehensive overview of the ecological health of Minnesota's watersheds. By applying a consistent statewide approach, the WHAF expands our understanding of processes and interactions that create healthy and unhealthy responses in Minnesota's watersheds. Health scores are used to provide a baseline for exploring patterns and relationships in emerging health trends.
Ecological Ranking of Parcels for Prioritizing Conservation Activities – NRRI
This site provides a mapping tool by which natural resource managers can visualize and interact with a high resolution map of the spatial data layers. Managers have the ability to specify the relative importance of habitat, soil erosion potential, or other components of the Environmental Benefits Index - a score which represents a summary of the above factors., and view how the ecological ranking of parcels changes under different scenarios.
Minnesota Watershed Nitrogen Nitrogen Reduction Planning Tool
Minnesota Watershed Nitrogen Reduction Planning Tool - Nitrogen BMP Spreadsheet (Lazarus et al., 2013)
The Watershed Nitrogen Reduction Planning Tool (Excel Spreadsheet) was developed as part of the Nitrogen in Minnesota Surface Waters Study by researchers at the University of MInnesota and Minnesota Pollution Control Agency. The project purpose was to develop a framework for a watershed nitrogen planning aid that could be used to compare and optimize selection of "Best Management Practices" (BMPs) for reducing the nitrogen load from the highest contributing sources and pathways in the watershed.
NBMP Tool - Maps
Cost Analysis of Minnesota Nutrient Reduction Strategy
An analysis of costs is provided in Chapter 5.5 of the Minnesota Nutrient Reduction Strategy for both wastewater nutrient removal and agricultural BMP implementation.
Excerpts from Chapter 5: Point and Nonpoint Source Reductions
Wastewater
Agricultural BMPs
The Minnesota Nutrient Reduction Strategy - MPCA
Appendix C: Program Recommendations