The Boise River, which is already running cold and fast, will continue to get more water.
Flows will increase to about 3,000 cubic feet per second to allow for more room in the reservoir for the melting snow and more rain.
Officials want to remind people to be careful near the river and to be mindful on the Boise Greenbelt.
Last month, a man drowned after slipping into the river near the Boise Whitewater Park.
