Application of SWAT to assess the Application of SWAT to assess the Illinois Conservation Reserve Illinois Conservation Reserve Enhancement Program in the Enhancement Program in the

La Moine River BasinLa Moine River Basin

T. Kevin O’Donnell1, Claire Baffaut2, David L. Galat3

1School of Natural Resources2 Food and Agricultural Policy Research Institute

3U.S. Geological Survey, Fish and Wildlife Research Unit

University of Missouri-Columbia

Talk OutlineTalk Outline

Illinois Conservation Reserve Illinois Conservation Reserve Enhancement Program (CREP)Enhancement Program (CREP)

BackgroundBackgroundImplementationImplementationGoals and objectivesGoals and objectives

Illinois CREP effects in the La Moine River Illinois CREP effects in the La Moine River BasinBasin

WatershedWatershed--scale hydrologic modelscale hydrologic modelSediment yieldSediment yield

Illinois Conservation Reserve Illinois Conservation Reserve Enhancement Program (CREP)Enhancement Program (CREP)

Landscape/watershed scale programLandscape/watershed scale programSupplement to the Conservation Reserve Supplement to the Conservation Reserve Program (CRP) initiated in 1998Program (CRP) initiated in 1998Extension of typical CRP contracts to:Extension of typical CRP contracts to:

30 years30 years50 years50 yearsPermanent Easement Permanent Easement

ILCREP Eligibility Requirements ILCREP Eligibility Requirements and Implementation Strategyand Implementation Strategy

100100--year floodplain year floodplain (85%)(85%)Highly Highly erodibleerodible land land adjacent to riparian adjacent to riparian buffer (15%)buffer (15%)Common practicesCommon practices

Riparian buffers (CP22)Riparian buffers (CP22)Wetland restoration Wetland restoration (CP23)(CP23)

Illinois Conservation Reserve Illinois Conservation Reserve Enhancement Program (CREP)Enhancement Program (CREP)

Goal: Goal: ““Reduce the contribution of Reduce the contribution of sensitive sensitive agricultural landagricultural land to sedimentation to sedimentation occurring in the Illinois Riveroccurring in the Illinois River””ObjectivesObjectives

““ReduceReduce……silt and sediment entering the silt and sediment entering the Illinois River by 20 percentIllinois River by 20 percent””Additional goals for nutrient reduction and Additional goals for nutrient reduction and increases in fish, waterfowl, and mussel increases in fish, waterfowl, and mussel populations populations

Farm Service Agency. 2004. Illinois CREP Programmatic Environmental Assessment. U.S. Department of Agriculture, Washington, D.C.

ObjectivesObjectives

Evaluate the success of the Illinois CREP Evaluate the success of the Illinois CREP in the La Moine River Basin based on:in the La Moine River Basin based on:

Current location of Current location of BMPsBMPs

Sediment reductionSediment reduction

MethodsMethodsPredict hydrologic and physical processes Predict hydrologic and physical processes at the watershedat the watershed--scalescaleSoil and Water Assessment Tool (SWAT) Soil and Water Assessment Tool (SWAT) version 2000version 2000

(Benson 2004)

Collect data important to model inputsCollect data important to model inputsSoils (NRCSSoils (NRCS--StatsgoStatsgo))Land use (Illinois Dept. of Agriculture)Land use (Illinois Dept. of Agriculture)Climate (NOAA)Climate (NOAA)Topography (USGS)Topography (USGS)Land management (NRCS)Land management (NRCS)

Methods cont.Methods cont.

Collect data important to model inputsCollect data important to model inputsSoils (NRCSSoils (NRCS--StatsgoStatsgo))Land use (Illinois Dept. of Agriculture)Land use (Illinois Dept. of Agriculture)Climate (NOAA)Climate (NOAA)Topography (USGS)Topography (USGS)Land management (NRCS)Land management (NRCS)

Calibration and Validation ProcessCalibration and Validation ProcessStreamflowStreamflow (USGS)(USGS)Sediment Transport Curve (Illinois State Water Survey)Sediment Transport Curve (Illinois State Water Survey)

Methods cont.Methods cont.

Collect data important to model inputsCollect data important to model inputsSoils (NRCSSoils (NRCS--StatsgoStatsgo))Land use (Illinois Dept. of Agriculture)Land use (Illinois Dept. of Agriculture)Climate (NOAA)Climate (NOAA)Topography (USGS)Topography (USGS)Land management (NRCS)Land management (NRCS)

Calibration and Validation ProcessCalibration and Validation ProcessStreamflowStreamflow (USGS)(USGS)Sediment Transport Curve (Illinois State Water Survey)Sediment Transport Curve (Illinois State Water Survey)

Predict 30Predict 30--year effects of year effects of BMPsBMPs based on based on current watershed locationcurrent watershed location

Illinois CREP locations (Illinois Dept. of Natural Illinois CREP locations (Illinois Dept. of Natural Resources)Resources)

Methods cont.Methods cont.

Sediment Transport CurveSediment Transport Curve

Sediment Yield:Sediment Yield:Calibration PeriodCalibration Period

Sediment Yield Statistics:Sediment Yield Statistics:Pearson (RPearson (R22) and Nash) and Nash--Sutcliffe (RSutcliffe (RNSNS))

RR22 = 0.60 = 0.60 RRNSNS = 0.59 = 0.59

RR22= 0.74 = 0.74 RRNSNS= 0.74 = 0.74

DailyDaily

RR2 2 = 0.70 = 0.70 RRNSNS = 0.76 = 0.76

RR22 = 0.79 = 0.79 RRNSNS= 0.79 = 0.79

MonthlyMonthly

RR22 = 0.79= 0.79RRNSNS = 0.72 = 0.72

RR2 2 = 0.81= 0.81RRNSNS = 0.81 = 0.81

AnnualAnnual

Validation Period Validation Period (1991(1991--1998)1998)

Calibration Period Calibration Period (1981(1981--1986)1986)

Time ScaleTime Scale

Monthly/Daily Model ResidualsMonthly/Daily Model Residuals

Monthly residualsMonthly residualsSWAT predictions were not significantly SWAT predictions were not significantly different than sediment transport curvedifferent than sediment transport curve

Daily residualsDaily residualsSelected Selected exceedanceexceedance categories/months were categories/months were significantly differentsignificantly different

Illinois CREP EvaluationIllinois CREP Evaluation

0.3%0.3%1,943 1,943 tonnestonnes

Standard errorStandard error

--3.6%3.6%--21,000 21,000 tonnestonnes

Mean annual sediment Mean annual sediment change (30 years)change (30 years)

%%ValueValueMeasureMeasure

Illinois CREP EffectsIllinois CREP Effects

Illinois CREP EffectsIllinois CREP Effects

Sensitive Agricultural Land?Sensitive Agricultural Land?

ConclusionsConclusions

BroadBroad--scale, general objectives may not scale, general objectives may not costcost--effectively guide the Illinois CREPeffectively guide the Illinois CREP

Models can help refine implementation Models can help refine implementation plans at the initial stages of programsplans at the initial stages of programs

Develop targeted objectives for Illinois Develop targeted objectives for Illinois River subRiver sub--watershedswatersheds