Cosumnes River Preserve

Quick Facts

Cosumnes River Preserve


(916) 684-2816

Map Directions

Things To Do


Cosumnes River country holds a very special place among California landscapes and amazing recreation opportunities. The Cosumnes is a small river, a mere 80 miles long. Its headwaters in the El Dorado National Forest rise at only 8,000' above sea level. The Cosumnes River Preserve is home to California's largest remaining valley oak riparian forest, and is one of the few protected wetland habitat areas in the state. This habitat has been reduced by more than 90% of its historical occurrence in California. The Preserve includes 46,000 acres of central valley grasslands, vernal pools, wetlands and valley oak forests. The Cosumnes River is the only remaining unregulated (undammed) river on the western slope of the Sierra Nevada Mountains. In its lower reaches, it flows through one of the most biologically rich regions in California's Central Valley, before merging with the Mokelumne River to flow into the Sacramento-San Joaquin Delta and eventually the Pacific Ocean. The Cosumnes River Preserve was created to safeguard much of this unique landscape. Enjoy, "non-consumptive" recreational activities, such as bird watching, photography, nature study, hiking and paddling. A few specially designated areas have been set aside for limited hunting. Fishing is only allowed from a boat, in the river, and with the proper license.

Visitor center hours vary. Call before your visit.

Map of Cosumnes River Preserve

Latitude, Longitude: 38.267721, -121.405999



  • Bird Watching

    Nestled in the heart of California's Central Valley, The Preserve is a critical stop on the Pacific Flyway for migrating and wintering waterfowl. Over 250 species of birds have been sighted on or near the Preserve, including the State-listed threatened Swainson hawk, greater and lesser sandhill cranes, Canada geese and numerous ducks.

  • Auto/Motorcycle

    The Preserve's Driving Tour has become very popular with visitors. The tour allows them see to the scope of the Cosumnes River Project by highlighting Preserve properties that aren't open to the public. While the tour focuses primarily on the lower Cosumnes, it has optional Preserve destinations in the North Delta and base of the foothills at Howard Ranch. All of the driving is done only on the public roads. Driving Tour brochures are available at the Cosumnes River Preserve Visitor Center. The Visitor Center is staffed by volunteers on the weekends and Preserve staff tries to keep it open during the weekdays. Call before your visit to find out if the visitor center is open.

  • Fishing

    Fishing at the Preserve is allowed only from a boat on the waters of the main channel of the Cosumnes River and sloughs accessible from the Mokelumne River, but only during the proper seasons and with the proper license(s).

  • Hiking

    The trails, boardwalks and waterways are one of the great parts of the Preserve that are open to the general public. These areas are open from sunrise to sunset.

    Lost Slough Wetlands Walk is a one mile, universally accessible trail offers visitors an up-close experience into lush marshes, wetland plants, water birds, insects, and amphibians. There is also a wooden boardwalk, open from 10 a.m. to 4 p.m. daily, which can be accessed along the Wetlands Walk. The boardwalk meanders into the restored marshes of Lost Slough (located across Franklin Blvd. from the Visitor Center) and was built during the winter of 1994.

    The Cosumnes River Walk trail is a 3-mile round-trip trail, accessible from the bridge just north of the Visitor Center. The Nature Conservancy first opened the trail to the public in 1987. It is located primarily on raised levees that wind through a variety of habitats, including buttonbush thickets, native grasslands, valley oak riparian forest along the Cosumnes River, cottonwood/willow riparian forest, tule marsh, valley oak savannah and several restoration projects - including the oldest riparian restoration planting (planted winter '87-'88) and about 30 acres of restored seasonal marsh. Due to the rough nature of the terrain, the trail is not universally accessible. In addition, during the winter months, the natural flood cycle often results in complete inundation of the trail by floodwaters. However, most of the year the trail is open, from sunrise to sunset, to anyone who cares to use it. The Preserve's Trail Brochure is available online, or you may pick up a copy at the Visitor Center.

    The Rancho Seco Howard Ranch Trail is a 7-mile roundtrip trail. It starts at the Rancho Seco Recreational Area and winds around the north end of Rancho Seco Lake. The trail opened to the public in the summer of 2006. Landscape on the trail includes vernal pools, seasonal wetlands, riparian and marsh habitat, as well as dramatic views of oak woodland habitat and the Sierra Nevada Mountains in the distance.

  • Historic Sites

    The Cosumnes River Preserve Visitor Center is located along Franklin Blvd on the east side. The Visitor Center is open most weekends and closed on all holiday weekends. The Visitor Center is staffed by volunteers on the weekends and Preserve staff tries to keep it open during the weekdays. Call before your visit to find out if the visitor center is open.

    This building houses an exhibition room with interpretive displays and operates as an office for staff of the various partners, including the Bureau of Land Management, The Nature Conservancy, Sacramento Co. Dept. of Regional Parks and California Department of Fish and Game.

  • Hunting

    Hunting & Fishing is allowed on the river and in the sloughs, but hunters and fishermen must stay in their boats, there is no hunting or fishing from the banks. This is allowed only during the proper seasons and with the proper license(s).

  • Water Sports

    The lower Cosumnes River offers excellent flat water canoeing and kayaking opportunities during most of the year. The Cosumnes is the last free-flowing river from the mighty Sierra Nevada Mountains into the Great Central Valley. Paddlers can enjoy a scenic glide through the river's sloughs and main channel, cruising along riparian forest, oak woodland and through wetlands teeming with wildlife.

  • Wildlife Watching

    The free-flowing nature of the river allows frequent and regular winter and spring overbank flooding that fosters the growth of native vegetation and the wildlife dependent on those habitats. Many birds and animals can be seen at the preserve.


The best time to observe waterfowl is during the winter months. Many species of waterfowl spend their winters in the warmer climates that are south of the arctic freeze. Remains of the fall harvest and winter flooding provide ideal habitat for a variety of species that journey along the Pacific Flyway. Waterfowl, cranes, wading birds, and shore birds are seen from October to March; birds of prey from November to April. Songbirds are common in the fall and spring. Small boat access to Lost Slough from Delta Meadows Park.

When visiting the Cosumnes River Preserve, binoculars or cameras are nice things to bring. Also, sun protection, water, a light jacket, snacks and a trash bag.

Insect repellent is highly recommended, especially in spring and summer when ticks and mosquitoes are most active. There are no tick-related lyme disease cases in Sacramento County, but there is still the potential for these parasites to carry harmful diseases.

Park Partners

Nature Conservancy and other agencies

A cooperative habitat restoration effort of The Nature Conservancy, California Fish and Game, Ducks Unlimited and many other groups dedicated to restoration.

(916) 684-2816



From I-5 North, take Interstate 5 to the Twin Cities Road exit (marked with a binoculars sign for wildlife viewing) about midway between Stockton and Sacramento. Take Twin Cities Road exit and go East for exactly one mile, to the first stop sign. Turn right at the first stop sign, onto Franklin Boulevard, for 1.7 miles. The Visitor Center is located on the left side of Franklin Boulevard. Continue down Franklin Boulevard and park in the parking lot just past the Visitor Center.

From I-5 South, take Interstate 5 to the Thornton-Walnut Grove Road exit. Go east towards the Chevon gas station and turn left immediately after the Chevron station onto Thornton Rd. Follow Thornton Road north for about 2 miles and it will turn into Franklin Boulevard, continue north on Franklin crossing over the Thornton-Franklin bridge. The Visitor Center and parking are on your right, just after the bridge.

From Highway 99, take Highway 99 to the Twin Cities Road exit about midway between Stockton and Sacramento. Take Twin Cities Road west for about 6 miles and turn left onto Bruceville Road. Continue south on Bruceville Road and at the end turn right onto Desmond Road. Follow Desmond Road for about a mile over the Railroad tracks and turn left onto Franklin Boulevard. Continue down Franklin Boulevard and park in the parking lot just past the Visitor Center.

Phone Numbers


(916) 684-2816