A federal judge has handed a victory to the Corps of Engineers, by rejecting environmental groups' challenges to the agency's new plan for managing the flow of the Missouri River.

In a June 21 ruling, Judge Paul A. Magnuson of the U.S. District Court in Minnesota said the Corps' revised Master Water Quality Manual and 2004 operating plan for the Missouri are valid and that the agency should follow the new documents in operating the river.

Environmental groups had sued the Corps, seeking changes in the agency's plan that they say would provide more protection for endangered bird and fish species and make the river healthier.

Rebecca R. Wodder, president of American Rivers, a plaintiff in the case, said, "The Corps of Engineers has postponed the necessary changes in river flows for nearly 15 years, and we do not share the court's confidence that new flows will occur sometime in the future without a court order." The group says environmental organizations will review the ruling before deciding whether to appeal it.

The Corps issued the new Master Manual, the first rewrite of the document in more than 40 years, in March. The agency's plan cost an estimated $1.3 billion over the next 20 or 30 years, including hundreds of millions of dollars for habitat restoration.
Managing the river, which at more than 2,300 miles is the nation's longest, requires dealing with a variety of competing interests. They include those who live upstream and want more water held in reservoirs to boost recreational uses and downstreamers, who want more water released to facilitate barge traffic.