Oxbow restoration providing habitat for fish, wildlife
By Jean Caspers-Simmet
Date Modified: 05/30/2012 1:29 PM
WEBSTER CITY, Iowa —An oxbow restoration east of Woolstock is filled with water and providing habitat for fish and other wildlife.
Jake Peterson worked with Eileen Bader, a freshwater specialist with The Nature Conservancy working in the Boone River Watershed, to restore the oxbow on a farm owned by his father, Gerald.
The Petersons own Peterson Construction in Webster City. The company did the restoration work at the end of December and early January because of nice weather.
Peterson, an Iowa State University graduate who returned home to join the business, said he was working with Bader on some other conservation projects on his family's land when she told him about the oxbow project. She had identified potential oxbow restorations and one was on the Petersons' land.
"I got permission from my dad and ran with it," said Peterson.
An oxbow, according to Bader, is a meander of a river that has been cut off from present flow of water either by the process of a river's natural movement or as a result of channel straightening.
"Functioning oxbows provide numerous benefits to people including water filtration and flood storage," Bader said. "Oxbows also create habitat for wildlife, particularly birds and fish. The slow-moving water found in oxbows is critically important for the endangered Topeka shiner, a minnow that requires off-channel habitat to complete its life cycle."
Most oxbows are located adjacent to streams and are well suited to restoration because the land is usually not well suited for crop production.
Peterson said the oxbow restoration on his family's land is along White Fox Creek, a tributary of the Boone River located in Wright County.
"The oxbow was all silted in," Peterson said. "To restore it we dug out a little over 2,000 cubic yards of sediment. We sloped the sides down to the water. It's on CRP ground, and we'll re-seed the native grasses that we disturbed."
Water entered the dry oxbow as soon as the gravel layer was reached during excavation at about a depth of three feet, Bader said. Spring rains have filled it more, Peterson said.
Monitoring from other oxbow restorations shows reductions in nitrogen and phosphorus when oxbows are coupled with tile outlets, Bader said.
Prior to restoration, a fish survey was conducted and surface water quality monitoring done at the Peterson site. With the restoration complete, there will additional fish surveys and ground and surface water monitoring. Water samples will be taken bi-weekly from both the stream and oxbow and analyzed for fluoride, chloride, nitrite, nitrate, phosphate, sulfate levels and pH.
Monitoring data will provide a clearer understanding of sources of water entering the oxbow, the type of habitat maintained and the efficiency of the oxbow's natural nutrient processing capability, Bader said.
Peterson said that the National Fish Habitat Partnership, The Nature Conservancy, Iowa Department of Natural Resources and Iowa Soybean Association provided the funding for the restoration.
The Nature Conservancy, the Iowa Soybean Association, Iowa Department of Natural Resources, U.S. Fish and Wildlife Service, and the Sand County Foundation plan to restore three additional oxbows in the Boone River Watershed in 2012.
"I'm very happy with it, and I think all the other groups involved are pleased as well," Peterson said of the oxbow restoration.
Peterson said it is exciting that the Boone River Watershed was named one of "Ten Waters to Watch" by the National Fish Habitat Partnership.
He hopes the designation leads to more projects to help the Boone River.