Phoenix Lake is the primary drinking water supply for Sonora, Jamestown, Scenic View, and Mono Village. The lake is also a primary fill source for CAL FIRE helicopter operations. Phoenix Lake is an important natural resource too that supports migrating birds, aquatic wildlife, and wetland habitat.

Horizon has helped the Tuolumne County Utilities District (TUD) since 2010 to develop the Phoenix Lake Preservation and Restoration Plan (PLPRP) to restore lake capacity, reduce watershed sedimentation, improve water quality, and protect, enhance, and restore wetland habitat.

In summer 2020 sediment removal began at the lake. More than 160,000 cubic yards were removed to restore lake capacity, improve water quality, and protect wetland resources. Horizon provided biological monitoring and regulatory agency coordination during the construction process, working closely with TUD, construction manager Anchor QEA, and contractor Steve Manning Construction, Inc.