Pool 3/Upper Pool 4 Channel Management Study. Mississippi River 9-Foot Channel Project. Channel Management Program

摘要

The purpose of this study was to evaluate channel management in pool 3 and upper pool 4 on the Mississippi River. The study area is from the head of Lake Pepin upstream to Look and Dam 2 at Hastings, MN. A lateral current problem below Lock and Dam 2 might be solved by extending the lower guard wall, but this would need further study. Shoaling problems were identified in the Big River reach, and shoaling and associated channel maintenance requirements are needed at river miles 799-803. Restoration of 4 wing dams at river mile 805 is recommended to reduce shoaling. Fish habitat benefits will be achieved through notching 18 wing dams and partial removal of another. The notches are designed to promote the formation of scour holes and channels to improve bathymetric diversity. Construction of a new spot dike at Carter Slough (river mile 807.3) is recommended to prevent habitat degradation occurring as a result of a bypass of the existing spot dike, and to assure the long term integrity of pool 3.