Providing a consistent and reliable food source for waterfowl is the goal of a project on Sand Lake National Wildlife Refuge (NWR). Ducks Unlimited is working with U.S. Fish and Wildlife Service staff to build a new water control structure and repair a berm on an 80-acre wetland near the Columbia Dam on the refuge.
Efficient wetland management requires the ability to remove water and let the area dry out for a season. This process discourages growth of invasive species and allows beneficial wetland plants to germinate and grow, producing high quality seeds that provide waterfowl with the essential nutrients they need for migrating and nesting.
"We work with Sand Lake on a variety of projects. They mentioned the current structure was nonfunctional, and we had some money available and were looking for a project to take on," said Steve Donovan, Ducks Unlimited’s manager of conservation programs in South Dakota.
Funding for the project came from the James River Water Development District and a North American Wetlands Conservation Act grant. Additional funding was provided by DU and the U.S. Fish and Wildlife Service.
"The James River Water Development District is excited about this project because it retains water holding capacity to abate flooding impacts and works to improve water quality," Donovan said.
Ducks Unlimited Engineer for South Dakota, Maddie Saylor, says the old structures needed to be removed before the new structure could go in.
"The new structure features a reinforced concrete pipe connected to a vertical concrete headwall with a mounted canal gate. Opening and closing the gate will allow water to enter and exit the wetland," Saylor said.
The new structure will allow refuge staff to opportunistically control water levels in the wetland by means of gravity from the James River. When the river elevation comes up and the gate is open, water will be able to enter the wetland. When the river goes down water will remain in the unit as long as the gate is closed. Staff will be able to fine-tune management strategies without drought or heavy rains dictating the water depths in the wetland. This ability will prevent cattails from choking the wetland and will allow seed-producing plants like smartweed and wild millet to colonize, providing high quality food for waterfowl.
An article about the project appeared on AberdeenNews.com