Soil erosion and subsequent sediment delivered to streams and lakes is a serious water quality problem in Nebraska. Sedimentation of small reservoirs reduced flood-holding capacity. High nutrient runoff can lead to harmful algal blooms.

Nebraska now has a way to estimate the relative amount of soil erosion across the state on a daily basis. The Daily Erosion Project is a real-time, computer-based, daily estimate of soil erosion and water runoff occurring on hill slopes in sample watersheds across the state.

DEP is operated by Iowa State University, and it originally estimated daily soil erosion only in Iowa. Funding support has allowed the project to extend across Nebraska.

Real data

DEP is updated daily based on rainfall, soil type, land slope, and estimated land cover and management identified via remote-sensing tools. If ample rainfall occurs, soil erosion and water runoff from sample hillslopes within watersheds across the state are updated daily based on hydraulic unit code watersheds, and results are presented at the DEP interactive website.

Estimates by DEP are made with the Water Erosion Prediction Project hillslope erosion simulation model developed over the past 30 years by USDA’s Agricultural Research Service. High-speed computing allows the WEPP computer model to compute more than 200,000 model runs per day, completing and publishing the previous days results usually by 6 a.m. the next day.

A Twitter account, @dailyerosion, can provide a notice when the results have been posted.

The website includes an interactive menu that can be used to select dates in the past to see the erosion and runoff from any day of the year. Look back on the day of the big rain in your watershed, and see what the estimated erosion was.

The values you see will be an estimate based on an average land use condition for the watershed, focused on agricultural land use. Any given field will yield more or less soil erosion than what is published depending on the land use of that field and the amount of rainfall and runoff that actually occurred.

Franti is an associate professor of biological systems engineering at UNL.