Supporting Documents for Lower Pool 5 Channel Maintenance/Weaver Bottoms Rehabilitation Plan on the Upper Mississippi River

摘要

The Weaver Bottoms is a 4,000-acre backwater lake in Lower Pool 5 of the Upper Mississippi River. Over the past 20 years, Weaver Bottom has changed from a highly productive backwater marsh to a less productive wind-swept riverine lake. Loss of aquatic vegetation has been substantial over this time period in addition to a significant accumulation of sediments. These long-term habitat losses are associated with increased current velocity, sedimentation, and turbidity. Study results indicated that Weaver Bottoms could be substantially rehabilitated through modification of selected side channels and construction of a series of islands to reduce wind fetch. As a beneficial use, dredged material from maintenance of the nine-foot navigation channel by the St. Paul District Corps of Engineers was recommended for use in constructing many of the project features. Contents: Biological Assessment for Endangered Species; Operational; Hydraulics; Resource Analysis Program; Recreation.