The Iowa Department of Natural Resources (DNR) has begun draining Walnut Creek Marsh in Ringgold County to make improvements in the marsh toward preventing summertime fish kills, similar to the significant fish kill that occurred in mid July. The marsh will drain over the next few weeks.
Draining the marsh will allow the DNR to remove an excessive abundance of American Lotus, a likely contributor to the summer fish kill. The DNR will also consider other potential improvements such as increasing the depth of the marsh through dredging or increasing the height of the existing dam.
The DNR will re-stock fish once the marsh has refilled.
Walnut Creek Marsh suffered a significant summer fish kill in mid-July due to low dissolved oxygen conditions caused by decaying vegetation. The DNR continued to monitor water conditions after the fish kill and it was determined that aquatic life could not be sustained under the current conditions.
Press Release, August 13, 2014