Improving Watershed Model Inputs with Data from Concentrated Animal Feeding Operations

Session: 41b. - Great Lakes Harmful Algal Blooms Research from Watershed Influence to Ecosystem Effects

Colleen Long, University of Michigan, longcm@umich.edu
Rebecca Muenich, Arizona State University, rebecca.muenich@asu.edu
Awoke Dagnew, University of Michigan, awoke@umich.edu
Margaret Kalcic, Ohio State University, kalcic.4@osu.edu
Donald Scavia, University of Michigan, scavia@umich.edu

Abstract

Watershed models have been used to estimate loads and the spatial distribution of nutrient sources in western Lake Erie watersheds, but in doing so have had to make broad assumptions about manure application to cropland.  Furthermore, the baseline manure management assumptions typically used by modelers may not be accurate for watersheds where Concentrated Animal Feeding Operations (CAFOs) are prevalent.  As a case study, we examine the River Raisin Watershed, which empties into the Western Lake Erie Basin in southeast Michigan, and within which approximately 40% of all cattle are concentrated in 7 CAFOs.  We used publically available data on manure management at the CAFOs to provide updates to a calibrated Soil and Watershed Assessment Tool (SWAT) watershed model.  With it, we were able to 1) test the importance of assumptions regarding manure input data in SWAT models, and 2) examine the effects CAFOs may have on nutrient loads and critical source areas in the River Raisin Watershed.

1. Keyword
watersheds

2. Keyword
model studies

3. Keyword
nutrients