U.S. Fish & Wildlife Service logo A Unit of the National Wildlife Refuge System
Banner graphic displaying the Fish & Wildlife Service logo and National Wildlife Refuge System tagline

National Wildlife Refuge

Maxwell Rd, off Interstate 5, 9 miles north off
Williams, CA   
E-mail: sacramentovalleyrefuges@fws.gov
Phone Number: 530-934-2801
Visit the Refuge's Web Site:
Gray horizontal line
Delevan National Wildlife Refuge

The Delevan National Wildlife Refuge is one of five refuges in the Sacramento Refuge Complex in the Sacramento Valley of north-central California. The 5,797-acre refuge is approximately 80 miles north of Sacramento and consists of over 4,500 acres of intensively managed wetlands and 1,200 acres of uplands.

More than 200,000 ducks and 100,000 geese come to the refuge each winter. With 95 percent of the wetlands of the central valley lost over the last 100 years, waterfowl have become increasingly dependent upon the refuges of the Sacramento Valley.

The refuge supports several endangered plants and animals: giant garter snake, wintering peregrine falcon and bald eagle, breeding tricolored blackbird, and a large colony of the endangered palmate-bracted bird's beak. Resident wildlife include grebe, heron, blackbird, beaver, muskrat, black tailed deer and other species typical of upland and wetland habitats.

Approximately 7,000 people hunt on the refuge each year.Ver limited wildlife observation is available along the Maxwell-Colusa Highway.

Getting There . . .
From Williams, take Interstate 5 north approximately 9 miles to the Maxwell Rd exit.

Drive east on Colusa-Maxwell Rd for approximately 4 miles to graveled Four Mile Rd., which parallels the west Refuge boundary.

From Colusa, travel north on the Colusa-Princeton Rd approximately 5 miles to Colusa-Maxwell Rd. Turn west and travel 4 miles to graveled Four Mile Rd.

Get Google map and directions to this refuge/WMD from a specified address:

Your full starting address AND town and state OR zip code

Google Maps opens in a new window

NOTE: When using this feature, you will be leaving the U.S. Fish & Wildlife Service domain. We do not control the content or policies of the site you are about to visit. You should always check site policies before providing personal information or reusing content.

These driving directions are provided as a general guide only. No representation is made or warranty given as to their content, road conditions or route usability or expeditiousness. User assumes all risk of use.

horizontal line

    Recreation and Education Opportunities
Wildlife Observation
Learn More >>

Management Activities
Refuge management emphasizes maintenance, enhancement, and restoration of habitat for migratory birds and endangered species, while providing as much natural diversity of indigenous flora and fauna as possible. Habitat is managed to create a mosaic of seasonal wetlands, semi-permanent and permanent wetlands, and uplands throughout the refuge.

Water levels are to encourage or discourage vegetation species, create suitable depths for a variety of wildlife, and minimize mosquito production. Since levee systems on local rivers that prevent natural flooding, most refuge wetlands are largely "artificial." Water is delivered through local irrigation districts.

Significant quantities of vernal pool-alkali meadow habitat are naturally filled with rainwater and provide some of the most diverse native flora and fauna in the Sacramento Valley. The refuge's annual habitat management plan sets objectives and directs management activities, prioritizing work on approximately 44 habitat units.

The plan includes floodup and drawdown dates, vegetation manipulation required, levee repairs, special management considerations, and other tasks required to meet refuge objectives. Standardized ground and aerial wildlife surveys and vegetation surveys are conducted throughout the year to inventory populations and document habitat use.

Each year units are evaluated by how well they met habitat and wildlife use objectives. The manager, biologist, and field crew revisit each unit annually, using the wildlife and habitat data to assess the previous year and to formulate the upcoming year's plan.

Various combinations of burning, grazing, herbiciding, and water management are used to control exotic or rank vegetation. Data on these efforts are stored in a computer database where they can be accessed, analyzed, and reported. Research is encouraged, and staff are involved with initiating and conducting studies that have direct applications to management.