DWR proposing to treat Navajo Lake in October in an effort to reset the fishery

Salt Lake City — In an effort to restore the trout fishery at Navajo Lake — and rid the waterbody of its overwhelming Utah chub population — the Utah Division of Wildlife Resources is considering a rotenone treatment later this fall. Before that fishery reset occurs, the DWR wants to meet with the public, explain the treatment process and answer questions about the proposed project.

DWR biologists will be holding a public meeting to discuss the project and answer questions about this upcoming treatment. The informational meeting will be held Sept. 10 at 6 p.m. at the Duck Creek Village Fire Station at 55 Mammoth Creek Road in Duck Creek Village. If you can't attend the meeting and want to provide feedback about the proposed treatment, email DWR Southern Region Aquatics Manager Richard Hepworth at This email address is being protected from spambots. You need JavaScript enabled to view it..

The proposed rotenone treatment for Navajo Lake, a popular fishing destination in Kane County, would tentatively occur mid-October. Rotenone is a natural substance that comes from the roots of a tropical plant in the bean family. It's a respiratory toxin to fish but isn't dangerous to people, pets or other wildlife, especially in the extremely low quantities that biologists will use to treat the lake.

Utah chubs have overrun Navajo Lake — making up over 90% of the fish in the waterbody — and currently outcompete the trout — rainbow, brook, splake and tiger trout — that are stocked there.

"Trout are the preferred species to fish for at this lake, which is why we are working to restore Navajo Lake as a prize trout fishery," Hepworth said. "With the low water levels this year due to drought, this treatment to reset the fishery would be much more cost effective, so we thought it would be good timing. We have exhausted all our other tools and efforts to restore the fishery, so this is our last option."

Rotenone treatments have proven to be an effective management tool when waterbodies are overrun by certain fish species. The DWR increased the daily fish limit to 16 trout (any size) on July 28 in order to give anglers an opportunity to catch and keep additional fish from Navajo Lake prior to the proposed rotenone treatment. That change is in effect until Oct. 31, 2021.