A Sedimentation Pond for Carver County Ditch #4A
2010 - Conservation Drainage
A 6000 square foot sediment pond, 3 feet deeper than the existing ditch bottom. As water moves over the sediment pond it will slow down and the suspended solids (sediment) will settle out to the bottom of the pond, keeping it out of the Minnesota River.
An estimated sediment load reduction of 137 tons/yr and phosphorus reduction of 170 lbs/yr was achieved through this project.
The purpose of this project is to install a sediment pond along County Ditch #4A to trap sediment and associated pollutants before entering into Bevens Creek which drains into the Minnesota River. Carver County Ditch #4A recently went through a redetermination of benefits process and state law now requires a buffer strip one rod (16.5 feet) wide to be maintained along the top of the ditch bank. The sediment pond, in combination with the buffer strip, will reduce the amount of sediments and pollutants that reach Bevens Creek.
The sediment pond will be 6000 square feet in area and 3 feet deeper than the existing ditch bottom. As water moves over the sediment pond it will slow down and the suspended solids (sediment) will settle out to the bottom of the pond. It is anticipated that the sediment pond will fill up in 3 -5 years at which time it will be cleaned out. Work will continue in the watershed to diminish upland erosion so the maintenance interval lengthens over time.