Accession Number:

ADA133511

Title:

Operation and Maintenance. 9-Foot Navigation Channel, Upper Mississippi River, Head of Navigation to Guttenberg, Iowa. Volume 1. Narrative.

Descriptive Note:

Final environmental impact statement.

Corporate Author:

CORPS OF ENGINEERS ST PAUL MN ST PAUL DISTRICT

Personal Author(s):

Report Date:

1974-08-01

Pagination or Media Count:

671.0

Abstract:

The operation and maintenance of the project provides for continued commercial and recreational navigation on the uppermost 245 river miles of the Mississippi River. The aesthetics of the present river setting and the production of fish and wildlife are, to a degree, dependent upon the continued operation and maintenance of the 9-foot channel. The current placement of maintenance dredge spoil requires that aquatic, semi-aquatic and terrestrial habitats adjacent to the navigation channel be converted to sandy islands which tend to eventually develop vegetation. Some of the dredge spoil is eroded and may be redeposited in entrances to backwater areas. The open, samdu spoil islands, although not developed for recreation, are subject to heavy public use. The spoil sites also support some use by wildlife, especially nesting sites for turtles. Adverse environmental impacts results in the unavoidable loss of aquatic and terrestrial habitat. The placement of dredge spoil frequently results in dredged material spreading out into off-channel areas. Turbidity is generated during channel maintenance operations, which tends to bury submerged aquatic vegetation, bottom-swelling aquatic invertebrates and fish eggs. The respiratory organs for invertebrates and fish can be damaged by excessive turbidity.

Subject Categories:

  • Civil Engineering

Distribution Statement:

APPROVED FOR PUBLIC RELEASE