Butte Basin NAWCA II: Gray Lodge Wildlife Area

This project is one of 10 individual project sites included in the Butte Basin and Colusa Trough Wetland Habitat Project.  New work conducted by the overall project improved 2,573 acres of habitat in this region.  The region is extremely important for migrating and wintering waterfowl, shorebirds, and other waterbirds.  The Central Valley, which includes this region, winters up to 90% of the Pacific Flyway's population of northern pintails and about 60% of its overall population of waterfowl.  At times, the Central Valley supports 20% of the continent's waterfowl population.  In addition to providing critical habitat for waterfowl, the Butte Basin and Colusa Trough region is also of major importance to several special-status species including the giant garter snake, spring-run chinook salmon, winter-run chinook salmon, and Central Valley steelhead.

The habitat improvement work accomplished by the overall project is extremely important.  The project increased wetland acreage for migrating and wintering waterfowl and other waterbirds, increased riparian acreage for neotropical migrants, improved water quality, improved water conveyance and control capabilities to allow better habitat management and improve efficiency of water use, and provided fish-safe water to many acres of wetlands and wildlife-friendly agriculture (i.e., winter flooded rice).

Gray Lodge Wildlife Area (WA) is located in the Butte Basin and is owned and managed by the California Department of Fish and Game.  Work at this site enhanced 979 acres of palustrine emergent wetlands and 230 acres of wetland-associated uplands.  This project was the fourth phase of the multi-phase Gray Lodge WA Water Delivery Improvement Project.  The overall project consists of redesigning and renovating the water delivery system at Gray Lodge WA and will improve water management capabilities on one of the most important wetland areas in the Pacific Flyway.  Activities completed as part of this fourth phase of work consisted of conducting a topographic survey and preparing an engineering design, constructing levees, excavating water conveyance channels, constructing a major water distribution structure and a road culvert structure, installing siphons and water control structures, and managing construction.

The project work completed at Gray Lodge WA improved the water supply to 1,209 acres of habitat.  Improving the water conveyance system to allow high-quality surface water from the local irrigation district to be delivered, has reduced groundwater-pumping costs and improved wetland management capabilities and habitat quality.  This work has improved habitat conditions for a variety of waterfowl and other wildlife.  Project work will benefit both the open and closed areas of the Wildlife Area.