Explore Watersheds
Interactive Map: Alameda County Watersheds
Alameda County is made up of many interconnected watersheds that cross city boundaries and natural landscapes. These watersheds shape how rain and runoff move through creeks, channels, and neighborhoods before reaching the Bay.
Explore the watersheds to learn how water flows through your community, where creeks connect, and how local restoration and stewardship efforts are helping protect these vital systems.
Alameda County Watersheds on Google Earth
If you are interested in downloading these interactive watershed map files via Google Earth (KMZ files), you must have Google Earth Pro downloaded to your computer or electronic device. Using Google Earth Pro, you can download either of the following watershed maps:
Watershed Details
- Size
- 8 square miles
- Flow
- A group of small streams flowing from the western face of Mission Peak, joining and discharging into Coyote Creek in south San Francisco Bay
- Includes
- Agua Fria Creek, Toroges Creek, Scott Creek, and engineered channel Lines A, B, C, and D, which artificially link the creeks together near the bay.
- Open Channel
- 18.6 miles
- Size
- Including Alameda County and eastern Santa Clara County, this watershed is 660 square miles in area, the largest watershed on the eastern shore of the San Francisco Bay. Only 30 square miles, or 5% of the watershed, are located in western Alameda County.
- Flow
- Alameda Creek heads in the rugged hills of the Diablo Range, draining from as far south as Mount Hamilton and as far east as Altamont Pass. Major tributaries join Alameda Creek in Sunol Valley. The creek then cuts through Niles Canyon and flows across the East Bay plain to the eastern shore of San Francisco Bay.
- Includes
- Major tributaries in western Alameda County are Dry Creek, Crandall Creek, and Lines J-2 and J-3. These flow into the Alameda Creek Flood Control Channel, an 11-mile-long channel built in the early 1970s replacing the natural creek.
- Cities
- Fremont, Newark
Subwatershed of Alameda Creek Watershed
- Size
- 74 square miles
- Flow
- The Upper Alameda Creek watershed is a subwatershed of the 661 square-mile Alameda Creek watershed, the largest watershed draining to the eastern shore of the San Francisco Bay.
- Includes
- Alameda Creek starts in the rugged hills of the Diablo Range and flows northwest through broad Sunol Valley, then turns west to run through steep Niles Canyon. Arbitrarily designated, \"Upper\" Alameda Creek becomes \"Lower\" Alameda Creek about midway through the canyon.
- Cities
- Alameda Creek east of Stonybrook Creek, Stonybrook Creek, Sheridan Creek, Pirate Creek, Welch Creek, Leyden Creek, Indian Joe Creek, Whitlock Creek, Valpe Creek.
Subwatershed of Alameda Creek Watershed
- Size
- 44 square miles
- Flow
- Alamo Canal drains northern Amador Valley and a portion of the hills south of Mount Diablo.
The Alamo Canal ends at its junction with Arroyo Mocho, where both flow into Arroyo de la Laguna, which eventually flows into Alameda Creek. - Includes
- Alamo Canal, Alamo Creek, West Branch Alamo Creek, South San Ramon Creek, Coyote Creek, Norris Creek, Oak Creek, Big Canyon Creek, Martin Canyon Creek, Dublin Creek, Gold Creek, and Tehan Canyon.
- Cities
- San Ramon, Dublin, Pleasanton
- Open Channel
- 75 miles
Subwatershed of Alameda Creek Watershed
- Size
- 99 square miles
- Flow
- Heads in the rugged mountains of the Diablo Range near Mount Hamilton, and flows north into Calaveras Reservoir.
- Includes
- Arroyo Hondo, Calaveras Creek, Isabel Creek, Long Branch, Hog Slough, Smith Creek, Sulphur Creek
- Cities
- none
- Open Channel
- 216 miles
Subwatershed of Alameda Creek Watershed
- Size
- 29 square miles
- Flow
- The Arroyo de la Laguna watershed drains flatlands and hills of the southern Amador Valley, and transmits flow from six other subwatersheds including Alamo Canal, Arroyo Mocho, Arroyo Mocho Canal, Arroyo Las Positas, and Arroyo del Valle. Arroyo de la Laguna then flows south to Sunol Valley, where it joins Alameda Creek.
- Includes
- Arroyo de la Laguna, Sinbad Creek, Pleasanton Canal, Kottinger Creek, Mission Creek, Sycamore Creek, Happy Valley Creek, Sheep Camp Creek, and Vallecitos Creek
- Cities
- Pleasanton, Sunol
- Open Channel
- 61 miles
Subwatershed of Alameda Creek Watershed
- Size
- 54 square miles
- Flow
- Drains a narrow rugged canyon that extends approximately 20 miles southeast of Livermore, to its headwaters in northern Santa Clara County.
- Includes
- Arroyo Mocho, Tunnel Creek, Mendenhall Springs
- Cities
- Livermore
- Open Channel
- 114 miles
Subwatershed of Alameda Creek Watershed
- Size
- 81 square miles
- Flow
- Drains the Altamont Pass
- Includes
- Arroyo Las Positas, Altamont Creek, Arroyo Seco, Cayetano Creek, Collier Canyon Creek, Cottonwood Creek, Frick Lake
- Cities
- Livermore
- Open Channel
- 152 miles
Subwatershed of Alameda Creek Watershed
- Size
- 168 square miles
- Flow
- Arroyo del Valle heads in the rugged mountains of the Diablo Range and flows northwest toward Livermore Valley. Before reaching the valley, it is impounded to create Lake Del Valle. Once released at the dam, the creek flows along the south side of the valley to join Arroyo de la Laguna in Pleasanton.
- Includes
- Arroyo del Valle (also known as Arroyo Valle), Dry Creek, Shafer Creek, Trout Creek, Sycamore Creek, Colorado Creek, Arroyo Bayo, San Antonio Creek, Jumpoff Creek, Sulphur Springs Creek, Sweetwater Creek, Beauregard Creek, Lake Del Valle.
- Cities
- Livermore, Pleasanton
- Open Channel
- 383 miles
- Size
- 6.23 square miles
- Flow
- From the hills west of Skyline Boulevard in Oakland, to Damon Slough and San Leandro Bay
- Includes
- Rifle Range Branch, Melrose Highlands Branch, County Club Branch, and 73rd Ave Branch
- Open Channel
- 7.8 miles
- Size
- 2.8 square miles
- Flow
- Drains into Airport Channel, San Leandro Bay and surrounding San Francisco Bay or Oakland Estuary.
- Includes
- Bay Farm Island and the Oakland airport
- Cities
- Alameda, Oakland
- Open Channel
- 2.1 miles, consisting of engineered channels in artificial fill over the former tidal marsh.
- Size
- 2.78 square miles
- Flow
- From the flatlands of western San Leandro to San Francisco Bay
- Includes
- A network of storm drains and canals
- Open Channel
- 1.7 miles, no natural creeks
- Size
- 2.9 square miles
- Flow
- Starts in the Berkeley hills along Grizzly Peak Boulevard and flows across north Berkeley and Albany to San Francisco Bay south of Albany Hill
- Includes
- Village Creek (Lower Marin Creek), Upper Marin Creek, and Blackberry Creek
- Open Channel
- 4.6 miles
Part of the Alameda Creek Watershed
- Size
- 6.5 square miles
- Flow
- From urban flatlands of Fremont into the Coyote Hills marsh, where the water is cleaned naturally, then through a pipe under the levee into the Alameda Creek Flood Control Channel.
- Includes
- Crandall Creek and Ardenwood Creek (now engineered channels) and a network of underground storm drains.
- Cities
- Fremont
- Open Channel
- 6.4 miles
- Size
- 3.1 square miles
- Flow
- Heads in the Berkeley Hills along Grizzly Peak Boulevard in the town of Kensington and flows across the Cities of El Cerrito and Albany to San Francisco Bay.
- Includes
- North Fork Cerrito Creek, Cerrito Creek, Middle Creek, and other unnamed tributaries.
- Cities
- El Cerrito, Kensington, Albany
- Open Channel
- 3.9 miles
Part of the Alameda Creek Watershed
- Size
- 9.9 square miles
- Flow
- From Walpert Ridge in the East Bay hills to the confluence with the Alameda Creek Flood Control Channel.
- Includes
- Dry Creek, the South Fork of Dry Creek, and an extensive network of small tributaries and canyons.
- Cities
- Union City
- Open Channel
- 26 miles, mostly natural creek.
- Size
- 2.6 square miles
- Flow
- Starts along the ridge near Bishop O'Dowd High School as a network of underground storm drains that flows across south Oakland and emerges as an engineered channel flowing into San Leandro Bay.
- Cities
- Oakland
- Open Channel
- 1.8 miles of engineered channel
- Size
- 9.4 square miles
- Flow
- Heads at the ridge near Fairmont Hospital and collects urban runoff from a wide area of urban San Leandro, discharging into San Francisco Bay near the San Leandro Marina.
- Includes
- A network of canals and underground storm drains and one small creek along Fairmont Drive.
- Cities
- San Leandro and the community of Ashland
- Open Channel
- 6.8 miles, mostly engineered channel
- Size
- 0.5 square miles
- Flow
- A network of underground storm drains or culverts in west Berkeley that drains into San Francisco Bay south of Albany Hill
- Cities
- Berkeley
- Open Channel
- None
- Size
- 2.6 square miles
- Flow
- Originates in the upper Rockridge neighborhood of Oakland and flows into the west arm of Lake Merritt
- Includes
- Rockridge Branch, Broadway Branch, and Glen Echo (Cemetery) Creek
- Cities
- Oakland
- Open Channel
- 1.43 miles
- Size
- 3.4 square miles
- Flow
- From downtown Hayward to the San Francisco Bay.
- Includes
- A network of underground storm drains feeding three major canals that join near the end of Winton Avenue and enter the bay at Hayward Landing
- Cities
- Hayward
- Open Channel
- 3.5 miles of engineered channel (canals)
- Size
- 3.0 square miles
- Flow
- Drains much of the City of Piedmont into the east arm of Lake Merritt
- Includes
- Small creeks that converge downstream including Pleasant Valley Creek, Indian Gulch (also known as Trestle Glen Creek), Bushy Dell Creek, and Wildwood Creek
- Cities
- Piedmont, Oakland
- Open Channel
- 2.0 miles
- Size
- 0.3 square miles
- Flow
- Drains an industrial area of Hayward into San Francisco Bay near the San Mateo Bridge
- Cities
- Hayward
- Open Channel
- 1.0 mile
- Size
- 25.1 square miles
- Flow
- Starts in the foothills of the Diablo Range near Mission Peak and flows across the flatlands and into Mud Slough and Coyote Creek and eventually into south San Francisco Bay
- Includes
- Morrison Creek, Vargas Creek, Mission Creek, Washington Creek, Sabercat Creek, Canada del Aliso Creek, Agua Caliente Creek, and Laguna Creek
- Cities
- Fremont
- Open Channel
- 44.6 miles
Part of the Alameda Creek Watershed
- Size
- 1.9 square miles
- Flow
- Drains a residential area into the Alameda Creek Flood Control Channel and eventually into south San Francisco Bay
- Cities
- Union City
- Open Channel
- 2.2 miles
- Size
- 3.5 square miles
- Flow
- Originates along Skyline Boulevard in the Oakland hills and drains to San Francisco Bay by way of Damon Slough
- Includes
- Horseshoe Creek, Chimes Creek, Lion Creek (a.k.a. Leona Creek, Arroyo del Leon), Merritt College, and Mills College.
- Cities
- Oakland
- Open Channel
- 4.1 miles
- Size
- 12.8 square miles
- Flow
- From the northeast edge of Fremont to Mowry Slough and southern San Francisco Bay.
- Includes
- A network of storm drains and parallel canals draining the gently sloping urban flatlands
- Cities
- Fremont, Newark
- Open Channel
- 14.9 miles, all of it engineered channels
- Size
- 4.9 square miles
- Flow
- Drains the flatlands of Newark and Fremont via a system of underground storm drains and engineered channels into Newark Slough and San Francisco Bay.
- Cities
- Newark, Fremont
- Open Channel
- 6.6 miles
- Size
- 3.4 square miles
- Flow
- A system of storm drains and underground culverts that drains the northern side of the island of Alameda into the Oakland Estuary.
- Cities
- Alameda
- Open Channel
- None
- Size
- 0.7 square miles
- Flow
- A network of underground storm drains through a small industrial area of Hayward that discharges into Mt. Eden Creek and San Francisco Bay
- Cities
- Hayward
- Open Channel
- None
- Size
- 5.6 square miles
- Flow
- Drains central Oakland into the Oakland Estuary.
- Includes
- Downtown Oakland, Brooklyn Basin, harbor areas, Highland Park, and the shores of Lake Merritt
- Cities
- Oakland
- Open Channel
- None
- Size
- 22 square miles
- Flow
- Drains the Hayward hills and a large area of the East Bay plain into the historical channel of Alameda Creek and into the San Francisco Bay.
- Includes
- Ward Creek, Zeile Creek, and Old Alameda Creek
- Cities
- Hayward, Union City
- Open Channel
- 31.5 miles
- Size
- 1.2 square miles
- Flow
- Drains a small, primarily industrial area east of the Oakland airport into San Francisco Bay near Oyster Bay Regional Shoreline
- Cities
- Oakland, San Leandro
- Open Channel
- 0.9 miles
- Size
- 0.1 square miles
- Flow
- Drains the Point Isabel area into San Francisco Bay
- Cities
- El Cerrito
- Open Channel
- None
- Size
- 5.6 square miles
- Flow
- Drains a portion of the Oakland hills and flatlands into East Creek and San Leandro Bay
- Includes
- Harrington Avenue Branch, Courtland Creek, Seminary Creek, Curran Branch, Laguna Branch, Berlin Branch, and Peralta Creek
- Cities
- Oakland
- Open Channel
- 4.8 miles
- Size
- 2.6 square miles
- Flow
- Drains the urban flatlands into Plummer Creek and the south San Francisco Bay
- Includes
- Zone 5, Line F-1 channel
- Cities
- Newark, Fremont
- Open Channel
- 7.0 miles
- Size
- 3.8 square miles
- Flow
- Drains south Berkeley from the Berkeley hills to Aquatic Park and San Francisco Bay.
- Includes
- The buried channels of Potter Creek and Derby Creek.
- Cities
- Berkeley, Emeryville
- Open Channel
- 0.2 miles
- Size
- 0.24 square miles
- Flow
- Drains a residential and industrial area into San Francisco Bay
- Cities
- Emeryville
- Open Channel
- None
Subwatershed of Alameda Creek Watershed
- Size
- 40 square miles
- Flow
- Several creeks drain this watershed, all flowing north into San Antonio Reservoir.
Water released from the dam flows northwest into Alameda Creek. - Includes
- San Antonio Creek, Apperson Creek, La Costa Creek, Indian Creek, San Antonio Reservoir
- Cities
- None. Unincorporated Alameda County
- Open Channel
- 79 miles
- Size
- 1.3 square miles
- Flow
- Drains small areas along the bayshore directly into San Leandro Bay.
- Cities
- Alameda, Oakland
- Open Channel
- None
- Size
- 49.4 square miles
- Flow
- Starts deep in the East Bay hills, and then flows across the East Bay plain from downtown San Leandro to San Leandro Bay.
- Includes
Grass Valley Creek, Miller Creek, Redwood Creek, Indian Creek, King Canyon Creek, Moraga Creek, Laguna Creek, Rimer Creek, Buckhorn Creek, San Leandro Creek
Parks and reservoirs:
Lake Chabot, Upper San Leandro Reservoir, Redwood Regional Park, Chabot Regional Park- Cities
- San Leandro, Oakland, Moraga
- Open Channel
- 78.3 miles, mostly natural creek
- Size
- 1.2 square miles
- Flow
- Drains urban neighborhoods and industrial areas near the marina via an engineered channel and two underground storm drains that discharge into San Francisco Bay.
- Cities
- San Leandro
- Open Channel
- 0.7 miles
- Size
- 48.2 square miles
- Flow
- The watershed begins in the East Bay hills at the Dublin Grade, incorporates the unincorporated communities of San Lorenzo, Ashland, Cherryland, Fairview, and Castro Valley, and includes portions of San Leandro and Hayward. San Lorenzo Creek flows generally west, entering central San Francisco Bay near Roberts Landing, west of San Lorenzo.
- Cities
- Castro Valley, Hayward
- Open Channel
- 105.9 miles
- Size
- 4.2 square miles
- Flow
- Starts in the Oakland Hills near Joaquin Miller Park and Montclair, flows through Dimond Canyon, the Fruitvale neighborhood, and into the Oakland Tidal Canal beside the Fruitvale bridge.
- Includes
- Palo Seco Creek, Shephard Creek, Cobbledick Creek, Whittle Avenue Branch, Sausal Creek
- Cities
- Oakland
- Open Channel
- 5.5 miles
- Size
- 1.0 square miles
- Flow
- Drains a small neighborhood in northwest Berkeley into a storm drain under Virginia Street, under I-880, and into San Francisco Bay
- Cities
- Berkeley
- Open Channel
- 0.2 miles, as short segments in residential back yards. Most of the creek has been replaced by underground storm drains.
- Size
- 1.0 square miles
- Flow
- Drains the southwest side of the island of Alameda from Central Avenue into San Francisco Bay. Most of the watershed drains through Alameda Lagoon, but areas near Crab Cove drain directly into the bay.
- Cities
- Alameda
- Open Channel
- None
- Size
- 3.0 square miles
- Flow
- Flows from Grizzly Peak in the Berkeley hills, through the University of California, downtown and residential areas of Berkeley, and enters the bay near University Avenue.
- Includes
- Hamilton Gulch, North Fork Strawberry Creek, Strawberry Creek
- Cities
- Berkeley
- Open Channel
- 3.2 miles
- Size
- 2.7 square miles
- Flow
- From downtown Hayward to San Francisco Bay. Its historical headwaters, Upper Sulphur Creek, have been artificially diverted into San Lorenzo Creek at 2nd Street to prevent flooding so are no longer a part of the watershed.
- Cities
- Hayward
- Open Channel
- 4.2 miles
- Size
- 6.7 square miles
- Flow
- From the north Oakland hills on either side of Highway 24, through Emeryville, and into San Francisco Bay at the Emeryville Crescent.
- Includes
- Harwood (Claremont) Creek, Vicente Creek (Grandview Branch), Tunnel Branch, Lake Temescal
- Cities
- Oakland, Emeryville
- Open Channel
- 4.6 miles
- Size
- 0.05 square miles
- Flow
- Drains the southwest-facing slope of Albany Hill into San Francisco Bay.
- Cities
- Albany
- Open Channel
- None
- Size
- 0.4 square miles
- Flow
- Drains the grass-covered western slope of the ridge directly into the diked former tidal marshes
- Includes
- Don Edwards National Wildlife Refuge
- Open Channel
- No channels and no storm drains
- Size
- 0.2 square miles
- Flow
- Drains a narrow strip of land along the shoreline.
- Cities
- Oakland
- Size
- 3.2 square miles
- Flow
- A network of storm drains in West Oakland
- Cities
- Oakland
- Open Channel
- None