Last Chance Ranch – Upper Pahsimeroi Phase Restoration

The Idaho Department of Fish and Game will implement habitat treatments on 0.87 miles of the upper the Pahsimeroi River near the town of May, ID. The Last Chance Ranch – Upper Pahsimeroi Phase Restoration is part of a multi-phase habitat restoration effort on the Last Chance Ranch property that will increase and enhance summer and winter foraging and rearing habitat for ESA listed juvenile salmonids. This project will be implemented in 2023 and is the first phase of a two-phase project on the Pahsimeroi River, with the downstream reach planned for construction in 2024. Current habitat conditions include limited instream habitat and channel complexity, disengaged lateral habitat, and degraded riparian habitat. The project site is under a conservation easement.



The goal is to increase habitat capacity for juvenile salmon and steelhead. IDFG is working with the Bureau of Reclamation to develop designs, incorporating an aggressive approach to fish habitat and floodplain connectivity. Multiple project actions are prescribed to meet this objective and include: 1) installing several types of large and small woody debris to improve instream habitat and channel complexity, 2) utilizing both large wood and engineered riffles to raise grade and force a proportion of the flow into side channels and on the floodplain. 3) utilizing existing disconnected and excavated side channels to increase overall channel length, and lateral habitat connectivity, and 4) enhancing native riparian vegetation by planting and seeding native species to provide long-term habitat and water temperature benefits to fish and other native species.



Note that engineered riffles, Beaver Dam Analogs, islands, and habitat benches are captured under “other engineered structures’ in the metrics.

Rehabilitation of the upper Pahsimeroi River on Last Chance Ranch is part of a multi-project effort to improve floodplain and riverine processes and functions on the mainstem Pahsimeroi River as well as several tributary spring channels on this property. This will directly increase habitat capacity for juvenile salmonids. Under the proposed project, current conditions will be improved by restoring instream channel habitat using woody habitat structures and engineered riffles to improve lateral connectivity to the floodplain and side channels. This will result in improved survival for all freshwater life stages. The project will provide increased foraging and rearing (summer and winter) opportunities for juvenile Chinook salmon and steelhead.