Water: Nonpoint Source Success Stories
Wisconsin: Section 319 Success Stories, Vol. III
Otter Creek Project:
319 National Monitoring Program Goals Met
Department of Natural Resources
101 South Webster Street
Madison, WI 53707
|Primary Sources of Pollution:|
|agriculture (cropland, dairy farms)|
|Primary NPS Pollutants:|
|fecal coliform bacteria|
|BMPs to control barnyard runoff and manure|
|nutrient management and reduced tillage on cropland|
|shoreline and streambank stabilization|
|more than 8,100 feet of streambank fencing|
|reductions in suspended solids (81 percent), total phosphorus (88 percent), ammonia nitrogen (97 percent), biological oxygen demand (80 percent), and fecal coliform bacteria (84 percent)|
The largely agricultural, 7,040-acre Otter Creek watershed drains to Lake Michigan via the Sheboygan River. Biological monitoring in the watershed has shown that the fish community lacks fishable numbers of warm-water sport fish, largely because of inadequate fish habitat and polluted water. Dissolved oxygen concentrations occasionally drop below Wisconsin's state standard of 5.0 milligrams per liter. In addition, bacteria levels exceed the state's recreational standard of 400 fecal coliforms per 100 milliliters in many samples.
Achieving program goals
Modeling and field inventories have identified critical areas needing treatment to achieve the project goals of the National Monitoring Program (http://h2osparc.wq.ncsu. edu /319index.html) [BROKEN] —improving the fishery, restoring the endangered striped shiner in Otter Creek, improving recreational uses by reducing bacteria levels, reducing pollutant loadings to the Sheboygan River and Lake Michigan, and restoring riparian vegetation.
Improved management of barnyard runoff and manure, nutrient management and reduced tillage on cropland, and shoreline and streambank stabilization are all being implemented to control sources of phosphorus, sediment, bacteria, and streambank erosion in the watershed. Best management practices (BMPs) installed on dairy farms include rainwater diversions, concrete loafing areas, filter screens to trap large solids in runoff, and grassed filter strips for treating runoff.
Paired watershed and upstream/downstream monitoring studies covering eight monitoring sites are used to evaluate the benefits of the BMPs. Monitoring sites are located above and below a dairy with barnyard and streambank stabilization BMPs. Habitat, fish, and macroinvertebrates are being sampled each year during the summer. Water chemistry is tracked through analysis of 30 weekly samples collected each year from April to October at the paired watershed and upstream/downstream sites. Runoff events are also sampled at the upstream/downstream sites and at the single downstream station site at the outlet of Otter Creek.
Key successesTo reduce upland soil erosion, more than 8,100 feet of streambank fencing was installed and a significant change in cropping practices was made. In the treatment watershed, 2 years of post-BMP monitoring data indicate that the system of BMPs was responsible for reductions in suspended solids (81 percent), total phosphorus (88 percent), ammonia nitrogen (97 percent), biological oxygen demand (80 percent), and fecal coliform bacteria (84 percent).
Rock County Land Conservation Department
440 North U.S. Highway 14
Janesville, WI 53546
|Primary Sources of Pollution:|
|agriculture (crop farming, heavily pastured areas, manure runoff)|
|Primary NPS Pollutants:|
|agricultural BMPs (barnyard runoff management, shoreline fencing, contour farming, reduced tillage, conservation crop sequence, strip crop, and critical area stabilization)|
|improved stream habitat, bank stability, in-stream cover, and fish communities, including natural reproduction of trout|
A medium-gradient (16 feet/mile) trout stream, Spring Creek drains about 6 square miles (3,500 acres) of Rock County farmland in the southeastern Wisconsin Till Plains Eco-region. Spring Creek is one of only three managed cold-water fisheries in Rock County. Although the creek had been capable of supporting stocked trout during the fishing seasons, it had been unable to provide habitat or water quality suitable for trout survival throughout the year. Because the waters of Spring Creek did not support natural trout reproduction, annual stocking of legal-size fish was required to provide a sport fishery.
The major land use in the Spring Creek watershed is cropland (83 percent), but land uses also include grass and wood (6 percent), wetlands (5 percent), development (3 percent), and some pasture (3 percent). Excessive amounts of sediment, nutrients, and bacteria degrade the creek's water quality, causing unbalanced fish communities with depressed populations and limited diversity. The upland sediment delivery in the watershed is 3,241 tons per year, or 92 percent of the entire watershed load, and cropland is the major sediment source in the watershed. Manure runoff from five animal lots created additional problems by contributing more than 500 pounds of phosphorus annually to the watershed. The headwaters of the stream had also lost much of their original habitat to channelization.
In 1991 Wisconsin's Department of Natural Resources selected Spring Creek as a "priority watershed management area" to restore stream habitat so that trout could reproduce naturally in its waters. Spring Creek was selected as one of five evaluation watersheds for a 7-year study to examine the responses of stream physical habitat, fish, and macroinvertebrates to watershed-scale best management practices (BMPs).
Between 1994 and 1999, Wisconsin implemented a number of watershed-scale BMPs to help reduce nonpoint source pollution in the Spring Creek watershed. By 1999 implemented BMPs included barnyard runoff and roof runoff management practices (diverting runoff away from animal waste); 1,600 feet of shoreline fencing; 289 acres of contour farming; reduced tillage (297 acres long rotation, 1,486 acres short rotation); 513 acres using conservation crop sequence; 24 acres of strip crop; critical area stabilization of 2 acres; and wetland preservation easements on 1.6 acres.
Wisconsin assessed stream habitat, fish and macroinvertebrates, and streambank erosion throughout Spring Creek at various times from 1993 through 1999, using two reference streams to effectively determine the effects of BMPs applied in the watershed. Sampling results indicated that upland and riparian BMP installations have significantly improved overall stream habitat quality, bank stability, in-stream cover for fish, and catch of all fishes. These improvements were more apparent at stream segments with streambank fencing than at segments without such fencing.
Trout populations in Spring Creek improved after BMP installation. The first-ever catch of young-of-the-year trout in 1999 indicated that Spring Creek has gained the ability to partially sustain its trout population through natural reproduction. Fish abundance also increased after BMP implementation, including a significant increase in the number of cool- and cold-water fishes.