proposed improvements is the sole focus of the Corps' environmental analysis. The “No Action” alternative represents the existing and future traffic levels that will occur without any additional navigation improvements.

ENVIRONMENTAL SETTING

The proposed project will affect one of our country's most significant ecosystems. The UMRS is a complex mosaic of bottomland forests, wetlands, and aquatic habitats which are home to over 150 species of fish and 44 species of Unionid mussels. Over 40 percent of North America's migratory birds use the Mississippi Flyway. There are 265,000 acres of the National Wildlife Refuge system along the Upper Mississippi River mainstem, and another 10,000 acres along the Illinois River. The five state agencies manage over 140,000 acres on the UMR and the Illinois DNR manages approximately 60,000 acres on the Illinois River.

ENDANGERED SPECIES ACT COMPLIANCE

The Service and the Corps recently completed formal consultation under Section 7 of the Endangered Species Act which assessed the effects of the existing Nine-foot Channel Navigation Project upon seven federally listed endangered and threatened species. These are the pallid sturgeon, Higgins' eye pearly mussel, winged maple leaf mussel, Indiana bat, bald eagle, decurrent false aster, and least tern. The Service determined that the continued existence of two species, the Higgins' eye pearly mussel and pallid sturgeon, would be in jeopardy if reasonable and prudent alternatives were not implemented by the Corps. The Service and the Corps are-still consulting with respect to the effects of the proposed system-wide navigation improvements described in the System Study. The recently completed consultation for the existing Nine-foot Channel Navigation Project will serve as the baseline condition for the proposed improvements consultation.

SUMMARY OF NAVIGATION STUDY ISSUES AND CONCLUSIONS

The current analysis is deficient.

Identifying and quantifying the environmental effects of commercial navigation traffic on UMRS natural resources has been a controversial issue for more than 25 years. During this time several efforts have investigated one specific navigation effect or another, but a comprehensive evaluation of all navigation-related effects has yet to be accomplished. Such an evaluation would examine the direct and indirect effects of passing towboats on natural resources as well as the effects of operation and maintainance (O & M) of the Nine-foot Channel Navigation Project (e.g., dredging, water level regulation, channel regulatory structures, impoundment). Since the current investigation has been presented as a “system-wide” study designed to identify needed improvements throughout the entire UMRS, the Service and state agencies believe that the system-wide cumulative effects of all Nine-foot Channel Navigation Project related activities should be examined as well.



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