Elk Lake, near Ruthven in eastern Clay County, will undergo a restoration project to improve its water quality, eliminate a rough fish population and provide quality habitat for fish and wildlife.
The Iowa Department of Natural Resources (DNR) will lower the water level in the 260-acre shallow natural lake this fall to install an in-lake outlet channel that will be used later to help to dewater the lake. It will remain about two feet low through the winter.
In the spring, the DNR plans to install a pump to remove the majority of the water that will allow them to install a barrier on the outlet preventing downstream fish from re-entering the lake. The water level will be held low through the winter to promote a total fish kill. It will begin to slowly refill in the spring of 2022 to allow emergent plants to germinate.
The current fishery is dominated by carp and bullheads that uproot aquatic plants, stir up the sediment and contribute to poor water quality. The combination of removing rough fish and lowering the water level will promote revegetation near the lake shore. Once established, those plants will remove nutrients from the sediment helping to prevent algae blooms, improve water quality and provide fish and wildlife important habitat.
“These shallow lakes need to be actively managed to promote aquatic vegetation and prevent carp and other rough fish entering the system,” said Rob Patterson, wildlife biologist with the Iowa DNR. “While a mechanical fish barrier isn’t the most effective means of preventing unwanted fish from entering the lake, it’s the option available to us right now and we want to get Elk Lake moving towards becoming a healthy system.”
While the lake is down, the DNR will be taking steps to maintain on-lake access and monitoring for any rough fish that survived the winter.
Patterson said he expects to see wildlife respond almost immediately to the project with shorebirds and other wildlife taking advantage of the low water and exposed mudflats, and waterfowl using the improved habitat in the fall of 2021. The lake will be restocked with northern pike, yellow perch, largemouth bass and bluegills in 2022 and anglers should begin catching fish in the late fall 2023, and more so in the spring of 2024.