Did You Know...

... that a recent dam modification project resulted in dramatic improvements to the habitat in a wildlife refuge in North Dakota, and enabled the exploration of several significant archeological sites? GEI Consultants, Inc. and the U.S. Fish and Wildlife Service undertook the rehabilitation project when the 38-foot-high dam that created Lake Ho, the heart of the Lake Ho National Wildlife Refuge, developed a safety problem. An emergency reservoir drawdown of the lake revealed 13 archeological sites and created a large mudflat that attracted record numbers of four endangered bird species. Any solution to the dam safety challenges would have to protect not only fish, but also the birds drawn to the new mudflats and the archeological sites.

The project schedule gave archeologists ample time to explore the exposed sites before the Service raised the reservoir. During construction of modifications to the dam, the Service used material demolition of an old spillway to create two islands in the lake. In early spring, when the reservoir is lowered, one of the islands becomes a mudflat, which provides nesting habitat for piping plovers and other birds. After nesting season, refuge personnel insert stoplogs to raise the reservoir, which enhances the fishery during the summer, a boon for the refuge's recreational value. The refuge has experienced dramatic increases in waterfowl population and recreational use.

(reprinted from the USCOLD Newsletter, November 1999, page 3)