From Field to Stream: Measuring Sediment and Nutrient Losses to Demonstrate the Need for Sub-Watershed Scale Conservation Planning

Kevin KuehnerSoil Scientist , CCA

SWCS Conference, Greensboro, North Carolina, July 27, 2015

Minnesota Challenge

• Tourism / outdoor recreation a lead industry• Agricultural products top export • Over 2,400 impairments requiring TMDLs

On-Farm Demonstrations

• Discovery Farms• Root River Field to

Stream Partnership

Field to Stream Partnership

• What’s the water quality like today? What are the long-term trends?

• What’s the range of sediment and

nutrient losses?

• How effective are new and existing BMPs? Targeted BMPs? What’s feasible?

• What's the best approach to engage producers and deliver cost-effective conservation?

Field to Stream Partnership

• Started in 2009 • Small scale, nested

monitoring design, 9 stations

• Minimum 10-year year effort

Study Phases

Implement Practices

Baseline Monitoring

& Assessments

Focus on Surface Runoff first and then practices for Nitrate-N

Phase 12010-2015

Phase II 2016-2020

Planning and Field Walkovers

Root River Watershed

75 Miles

35 milesGlacial Till

Karst Bluffland Karst

Headwaters

Crystal Creek

Bridge Creek

CornSoybeanForest, Pasture, Grass, Alfalfa, Other

Source: 2010 cropland data layer, NASS

Headwaters2,778 acres

94% cropland

Crystal Creek3,728 acres

78% cropland

Bridge Creek4,665 acres

64% cropland

Corn/soybean, no manure Corn silage, liquid dairy manure

Corn, soybean and alfalfa, liquid hog manure

Continuous corn grain or silage, liquid dairy or hog manure

Field #3= 96 acres Field #4= 21 acres

Field #2 = 18 acresField #1 = 26 acres

Tile

Edge of Field

Year-round sampling in the

harshest conditions

Root River Field to Stream: Average Annual Losses (2010-2014)

Average Losses

Avg. 46% frozen

Four months of the year accounted for more than 90% of the annual losses: March, April, May and June

4 sites, 5 year average, 2010-2014

Timing of Field Surface Losses

Existing practices inventory

Documented active erosion areas

Ag Conservation Planning Framework (ACPF)

Runoff Risk (Adjusted for Cropland in Grass Cover)

Conservation Planning Tools

ACPF tools developed by M. Tomer, S. Porter, D. James, USDA-ARS

14

Existing practices inventory

Documented active erosion areas

Ag Conservation Planning Framework (ACPF)

Stream Power Index (SPI)

Conservation Planning Tools

Stream Power Index, Statistical Analysis and Field Validation

Odds of erosion occurring at non-BMP sites are about 6.5 times higher than for BMP sites.

T. Dogweiler et al, Winona State Univ.

• The odds of erosion occurring are almost 8 times higher at Bridge Creek than at either Crystal Creek or the Headwaters Watershed.

• Sediment and Phosphorus concentrations are nearly 3X higher in Bridge Creek.

Stream Power Index and Water Quality

Sediment Total Phosphorus

Delivery Process

Producers sent their own letter to encourage their neighbors to participate

Field Walkovers to Initiate the Conversation

Field Walkovers

Walkover Status

100% of crop acres in Crystal and over 70% in Bridge Creek.

Preliminary Results

• Total of $1.1 million in conservation needs identified.

– About 1/3 of these costs were classified as a high priority.

Simple Report + Dedicated Planner

Field Walkovers

• Total of $700,000 dollars in structural and vegetative practice needs and fixes.

Field Walkovers

Next…seek funding for those that want it. Study goal is to have all high priority sites addressed in the next 2 years.

…..process builds the foundation with farmers and their advisors to then tackle nitrate-N loss strategies

-40% of this cost was associated with fixes to existing practices; a low hanging fruit.

From Field to Stream: Measuring Sediment and Nutrient Losses to Demonstrate the Need for Sub-Watershed Scale Conservation Planning

Special Thanks to Project Farmers,Partners, SWCDs/NRCS and MDA Monitoring Unit.

Kevin KuehnerSoil Scientist, CCA

SWCS Conference, Greensboro, North Carolina, July 27, 2015

THANK YOU!