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SWPI - Source Water Protection Initiative
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The Farm Security and Rural Investment Act of 2002 also referred to as the 2002 Farm Bill, substantially increased funding levels of conservation programs by nearly 80 percent above the level set under the 1996 Farm Bill.  While it is widely recognized that these conservation programs can protect millions of acres, the environmental benefits have not previously been quantified. Additionally, approximately 11,000 community water systems serving an estimated 180 million customers in the United States depend on surface water as a source of drinking water. Surface and subsurface drainage waters from agriculture, golf courses, suburban lawns and gardens, and numerous other land uses drain into drinking water sources.  Drainage waters often contain high concentrations of sediments, nutrients, and pesticides requiring costly treatment before water can be delivered to customers. The loadings to the streams also affect the ability of these waters to support aquatic life.


We are an integral component of the Source Water Protection Initiative (SWPI) and the ARS Conservation Effects Assessment Project Watershed Assessment Study (CEAP).  SWPI and CEAP are nationwide research projects with different research objectives.  SWPI is a collaborative effort among three midwestern watersheds and if focused on identifying best management practices for reducing the effects of agriculture on drinking water supplies.  Conversely, CEAP involves 14 watersheds in the United States and focuses on quantifying the effects of conservation practices intended to reduce effects of agriculture on the environment.  Our specific objectives for both projects are to:


  • Identify, implement, and quantitatively evaluate conservation practices aimed at minimizing offsite delivery of sediment, nutrients, and agrichemicals while enhancing aquatic communities in watershed landscapes located in the humid region of the U.S. The unique soils and climatic conditions within this region provide for some of the most productive crop land in the United States.  Environmentally safe and economically viable watershed scale management of the crop land in this region is critical not only to the producer, striving to be a good steward, but also to the consumer that uses the water resources for drinking and recreation.  

  • To identify a suite of practices that will protect and enhance the drinking water sources within the Upper Big Walnut Creek watershed and other agricultural watersheds in the Midwestern United States.

To meet our research objectives we are conducting field experiments to quantify the impacts of nutrient management practices, pesticide management practices, and herbaceous riparian buffers on the hydrology, water chemistry, and ecology of headwater streams in the Upper Big Walnut Creek watershed.  Our research projects will benefit the public and natural resources.    


Enhancing and protecting municipal drinking water sources (PDF) 



?USGS 11-digit HUC 05060001-130

? Drainage area of 190 square miles (492 km2)
? Spans a five county area
? 467 perennial  and intermittent stream miles
? Source water for 800,000 Columbus residents
? 180 day residence time in Hoover Reservoir
? 40 inches (1020 mm) average annual precipitation
? Systematic tile drained
? Soils classified as primarily hydrologic soil group C



                     Recreation                       Consumption                       Agriculture