Missouri River IA 06-WEM-1707

Assessment Comments

Assessment is based on (1) surveys of Nebraska fisheries biologists and consultation with DNR staff and (2) fish tissue monitoring in 1993.

Basis for Assessment

Continued to assess support of the Class B(WW) aquatic life uses as PS due to habitat alterations and flow modifications that resulted from development of the river for navigation uses in the mid-Twentieth Century.   This assessment was presented to the Nebraska fisheries biologist for the Missouri River and to DNR/EPD staff with historical involvement with Missouri River issues.   These professionals agreed with the assessment that aquatic life uses are "partially supported." The habitat alterations are due to channelilzation of the river, while the flow modifications are due primarily to control of river flows through the system of mainstem dams upriver from Sioux City.   Assessed support of fish consumption uses as FS based on results of RAFT sampling at Nebraska City in 1993:  levels of contaminants in the composite sample of carp fillets were all below 1/2 of the respective FDA action levels.