The Value of Wing Dams for Freshwater Mussels
Abstract
This note provides information on the value of wing dams, which reduce dredging requirements in large rivers* for freshwater mussels. Wing dams are longitudinal rock-rubble structures placed in waterways to develop and stabilize channels. Wing dams constrict low flows* which decreases maintenance dredging requirements (Shields 1983). These structures are usually oriented obliquely or at 90 deg to the current. Sediment deposition usually occurs between wing dams where current velocity is reduced relative to that in the unprotected main channel. Wing dams create quiescent areas that are similar to naturally occurring lentic habitats during normal and low flow (Beckett et al. 1983). In addition, wing dams themselves are a coarse-grained substrate used by aquatic insects and fishes (Conner* Pennington, and Bosley 1983; Pennington, Baker, and Bond 1983; and Shields 1983). At Winter's Landing in pool 7 of the upper Mississippi River, wing dams were placed to direct flow toward the Wisconsin shoreline to reduce the need for maintenance dredging. The US Army Engineer District, St. Paul is considering modifying these wing dams to further reduce dredging requirements. Because of these plans, the value of these wing dams had to be assessed for mussels, and a determination had to be made concerning whether the federally listed endangered mussel Lampsillis higginsi inhabited the area.
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 01, 1988
- Accession Number
- ADA382198
Entities
People
- Andrew C. Miller
- Robert M. Engler
- Robert Whiting