Officials working to divert water from spilling over Chesterfield Reservoir

CARIBOU COUNTY, Idaho (KIFI) - State and local officials are watching the Portneuf Dam at Chesterfield Reservoir as it started overflowing Wednesday morning.

The Portneuf Dam is located 30 minutes northwest of Soda Springs in Caribou County. This overflow is eroding portions of the Portneuf River below the spillway.

Multiple agencies are working together to try to stop the overflow and prevent further damage. Electric companies are out to make sure that nearby power poles do not fall into the river.

Caribou County officials have started to create diversions north of the reservoir to try to create less inflow. They also gathered lots of rocks and dirt to fill up the eroded land once they can.

The sheriff wants the overflow to be fixed by the end of Thursday.

"There's no seepage that's going on around the spillway. There are no other indicators that are being a red flag for us to be concerned the structure is going to fail at this point," Sheriff Adam Mabey said. "It's just that we need to get in there. We're working to divert the water that's coming into the reservoir at this moment. And once we get some of that water diverted, it'll stop going over the spillway."