A federal judge in Minnesota has ruled the Army Corps of Engineers can operate the Missouri as it has planned, turning away efforts by environmental groups to force low summer flows to help endangered pallid sturgeons and two bird species. Paul Johnston with the U.S. Army Corps of Engineers says the decision will allow the Corps to manage the river in line with the plan put forth by the Corps this past spring. The Corps received permission from the U.S. Fish and Wildlife Service to substitute at least 1,200 acres of habitat for the low summer flows. Liz Birnbaum with the environmental group American Rivers, one of the parties that sued the Corps in the first place, bemoans the decision.