A unique agreement has been struck that could improve the trout fishery in the upper Henry’s Fork of the Snake River, the Nature Conservancy said.
The pact signed by the U.S. Bureau of Reclamation, North Fork Reservoir Co. and the state’s Water District 1 will provide continuous water flows during the winter and spring in the reach of the Henry’s Lake outlet from the dam to Big Springs to benefit the fish and wildlife habitat.
The water storage in Henry’s Lake has historically provided improved summer flows, at the expense of the winter and spring flows.
During the winter and spring, the company will release water from Henry’s Lake in exchange for Reclamation water in other reservoirs, which will be available to North Fork irrigators during the summer irrigation season. The effort is intended to maintain a flowing stream where it would otherwise be dry.
“The watershed above Henry’s Lake is relatively small and the river in this area cannot be expected to flow without interruption unless we intervene and release water from storage during critical periods,” Snake River Watermaster Ronald Carlson said.
The nonprofit Nature Conservancy, which owns four miles of frontage on the lake outlet, has been working with the groups since it first bought the Flat Ranch downstream from the lake in 1994. The agreement is the culmination of the Conservancy’s efforts.
Reclamation will make up to 2,200 acre-feet of storage water available to irrigators, in exchange for an equal amount stored in Henry’s Lake. It will not affect either Reclamation or the reservoir company’s current water obligations.
“Now we can take steps to maintain this beautiful reach of Henry’s Fork and its fishery for generations to come,” said Guy Bonnivier, state director for the Conservancy.
A memorandum of understanding is planned that would call for the Conservancy and the Idaho Department of Fish and Game to provide Reclamation with information on water flows needed to protect the fish.
The Conservancy has built more than six miles of fence to protect wetlands on the ranch and has planted thousands of willows to restore the habitat.