A long-awaited low-flow test to determine how reduced flows in the Provo River affect the river's trout fishery was scheduled to begin Tuesday.

The study is a result of a request last winter by Dee C. Hansen, executive director of the Utah Department of Natural Resources, to the U.S. Bureau of Reclamation to determine the impacts of flows below 100 cubic feet per second from Deer Creek Reservoir.To protect the famous Provo River trout fishery, minimum flows of 100 cfs are required below Deer Creek to the Olmsted Diversion Dam.

The state and Reclamation agreed last December to delay the testing until this month. Flows were to be lowered Tuesday from 100 cfs to 60 cfs, in 10-cfs increments, to allow researchers to analyze the effects on trout habitat and the aquatic insects the fish eat.

Flows will return to 100 cfs Friday, and the report on the testing is to be completed by Dec. 1.