A joint study by the US Fish and Wildlife Service (FWS) and US Army Corps of Engineers (USACE) has concluded that dam operations on the Missouri river have disrupted water flow and could lead to the extinction of several animal species if remedial action is not taken. But the remedy could adversely impact river navigation for about three weeks a year.

The proposed action requires the release of water from the Missouri river dams each spring to build sand bars and improve spawning areas for fish. Selected habitat areas also require restoration. The USACE is currently revising its Missouri river water control guide to determine when to release water from local dams.

The Missouri river reforms were applauded by green groups who say changes to the Corps’ policy in the region are long overdue.