Since 1969, the Water Quality of San Francisco Bay Research and Monitoring Project has conducted water-column sampling along the deep channel of the San Francisco Bay-Delta system. Learn more about when and where we collect data.
When and Where We Collect Measurements
This long-term research and observation project collects measurements along the deep channel longitudinal axis of the San Francisco Bay-Delta system sampling the full salinity gradient. Access the full dataset on our Data Query for the Water Quality of San Francisco Bay Project Page. Sampling began on the R/V Polaris and since 2016, continues on the R/V David H. Peterson, named for a late founder of the project. Currently we conduct vertical water column sampling at 37 fixed locations spaced 3-6 kilometers apart. Coordinates for current and historical stations are listed in the tables below.
The San Francisco Bay is comprised of different regions:
- South Bay (stations 21–36): a marine lagoon surrounded by densely populated urban landscape. Includes a sub-region of Lower South Bay (stations 33-36).
- Central Bay (stations 16-22): a deep basin connected to the coastal Pacific Ocean. It bridges the South and North Bays.
- North Bay (stations 657-15): the estuary of California’s two largest rivers, the Sacramento and San Joaquin. It is comprised of San Pablo Bay, Suisun Bay, and the river stations.
As the goals of this research project evolve over time, the sampling frequency and spatial coverage have changed. Since 1993 we have conducted monthly cruises along the entire Bay-Delta system as part of the Regional Monitoring Program for Water Quality in San Francisco Bay. Additional cruises in the South and Central Bay are conducted during spring and when rapid water quality changes associated with phytoplankton blooms are predicted. Learn more about what we sample in San Francisco Bay.
See the map and tables below for more detailed information about the sampling locations.
Current Station Table
Station geographic locations, beginning with riverine end of cruise track.
Station | Location | Latitude (degrees) | Longitude (degrees) |
657 | Rio Vista | 38.151667 | -121.688333 |
649 | Sacramento River | 38.06 | -121.8 |
2 | Chain Island | 38.063333 | -121.851667 |
3 | Pittsburg | 38.051667 | -121.88 |
4 | Simmons Point | 38.048333 | -121.935 |
5 | Middle Ground | 38.06 | -121.98 |
6 | Roe Island | 38.065 | -122.035 |
7 | Avon Pier | 38.048333 | -122.096667 |
8 | Martinez | 38.03 | -122.151667 |
9 | Benicia | 38.056667 | -122.185 |
10 | Crockett | 38.06 | -122.208333 |
11 | Mare Island | 38.06 | -122.266667 |
12 | Pinole Shoal | 38.051667 | -122.311667 |
13 | North of Pinole Point | 38.028333 | -122.37 |
14 | Echo Buoy | 38.006667 | -122.405 |
15 | Point San Pablo | 37.973333 | -122.436667 |
16 | Charlie Buoy | 37.916667 | -122.446667 |
17 | Raccoon Strait | 37.878333 | -122.421667 |
18 | Point Blunt | 37.846667 | -122.421667 |
20 | Blossom Rock | 37.82 | -122.393333 |
21 | Bay Bridge | 37.788333 | -122.358333 |
22 | Potrero Point | 37.765 | -122.358333 |
23 | Hunters Point | 37.728333 | -122.336667 |
24 | Candlestick Point | 37.698333 | -122.338333 |
25 | Oyster Point | 37.67 | -122.325 |
26 | San Bruno Shoal | 37.636667 | -122.313333 |
27 | San Francisco Airport | 37.618333 | -122.291667 |
28 | North of San Mateo Bridge | 37.601667 | -122.27 |
29 | South of San Mateo Bridge | 37.58 | -122.245 |
29.5 | Steinberger Slough | 37.568333 | -122.21833 |
30 | Redwood Creek | 37.555 | -122.19 |
31 | Coyote Hills | 37.528333 | -122.158333 |
32 | Ravenswood Point | 37.518333 | -122.133333 |
33 | Dumbarton Bridge | 37.508333 | -122.121667 |
34* | Newark Slough | 37.495 | -122.098333 |
35 | Mowry Slough | 37.48 | -122.078333 |
36 | Calaveras Point | 37.471667 | -122.066667 |
* Sampling at this location for Station 34 began on 2/2/2016; for 1969 through 1/21/2016, the longitude degree was -122.093333.
Historic Station Table
Historic and non-standard stations geographic locations, temporal sampling range (first and last year data were collected), and mean low water depth.
Station | Geographic Location | Latitude (degrees) | Longitude (degrees) | Temporal Range | Mean Low Water Depth (meters) |
1 | Winters Island | 38.04 | -121.84 | 1969-1978 | 6.5 |
12.5 | Pinole Point | 38.04 | -122.315 | 1993-2001 | 6.7 |
19 | Golden Gate | 37.818333 | -122.471667 | 1969-1985 | 91 |
24.5 | South Bay | 37.685075 | -122.333328 | 1984 | 20 |
25.5 | South Bay | 37.6544 | -122.319169 | 1984 | 13.2 |
26.5 | South Bay | 37.626324 | -122.302245 | 1982-1984 | 8.7 |
27.5 | South Bay | 37.60956 | -122.281678 | 1983 | 9 |
28.5 | Geo Probe | 37.596667 | -122.235 | 1991-1995 | 15.7 |
30.5 | South Bay | 37.542166 | -122.177256 | 1984 | 18 |
31.5 | South Bay | 37.522796 | -122.145833 | 1982 | 12 |
33.5 | South Bay | 37.500692 | -122.112337 | 1985 | 13 |
405 | Reserve Fleet 2 | 38.048333 | -122.123333 | 1999-2002 | 12.7 |
407 | Reserve Fleet 4 | 38.071667 | -122.093333 | 1999-2002 | 9.6 |
411 | Garnet Sill | 38.096667 | -122.058333 | 1999-2002 | 7.3 |
650 | Sacramento River | 38.071667 | -121.775 | 1984-1988 | 10 |
651 | Sacramento River | 38.078333 | -121.763333 | 1980-1999 | 10 |
652 | Towlands Landing | 38.086667 | -121.746667 | 1977-1984 | 7 |
653 | Mid-Decker Island | 38.105 | -121.72 | 1984-2015 | 10.1 |
654 | Sacramento River | 38.105 | -121.708333 | 1984 | 10 |
655 | North of Three Mile Slough | 38.121667 | -121.701667 | 1980-1988 | 10.1 |
659 | Old Sacramento River | 38.178333 | -121.666667 | 1977 | 10.1 |
662 | Prospect Island | 38.226667 | -121.673333 | 1977 | 10.1 |
NOTE: From Aug 1999 through Jan 2002, Suisun Bay stations 405, 407 and 411 were sampled instead of standard channel stations 5, 6, and 7.
Below are other science pages associated with the Water Quality of San Francisco Bay project.
Water Quality of San Francisco Bay Research and Monitoring Project
Sampling Methods for the Water Quality of San Francisco Bay Project
Research Vessel David H. Peterson
Directly measured parameter data (depth, chlorophyll-a, dissolved oxygen, suspended particulate matter, extinction coefficient, salinity, temperature, nutrients) are available from the locations below:
USGS Measurements of Water Quality in San Francisco Bay (CA), 2016-2021 (ver. 4.0, March 2023)
Phytoplankton Species Composition, Abundance and Cell Size in San Francisco Bay: Microscopic Analyses of USGS Samples Collected 1992-2014
Directly measured parameter data (depth, chlorophyll-a, dissolved oxygen, suspended particulate matter, extinction coefficient, salinity, temperature, nutrients) are available from the locations below:
Data Query for the Water Quality of San Francisco Bay Project
Since 1969, USGS has collected water-quality data along the deep-channel longitudinal axis of the San Francisco Bay-Delta system at 37 fixed locations spaced 3-6 kilometers apart. The Water Quality of San Francisco Bay Data Query provides access to the entire dataset.
- Overview
Since 1969, the Water Quality of San Francisco Bay Research and Monitoring Project has conducted water-column sampling along the deep channel of the San Francisco Bay-Delta system. Learn more about when and where we collect data.
When and Where We Collect Measurements
This long-term research and observation project collects measurements along the deep channel longitudinal axis of the San Francisco Bay-Delta system sampling the full salinity gradient. Access the full dataset on our Data Query for the Water Quality of San Francisco Bay Project Page. Sampling began on the R/V Polaris and since 2016, continues on the R/V David H. Peterson, named for a late founder of the project. Currently we conduct vertical water column sampling at 37 fixed locations spaced 3-6 kilometers apart. Coordinates for current and historical stations are listed in the tables below.
The San Francisco Bay is comprised of different regions:
- South Bay (stations 21–36): a marine lagoon surrounded by densely populated urban landscape. Includes a sub-region of Lower South Bay (stations 33-36).
- Central Bay (stations 16-22): a deep basin connected to the coastal Pacific Ocean. It bridges the South and North Bays.
- North Bay (stations 657-15): the estuary of California’s two largest rivers, the Sacramento and San Joaquin. It is comprised of San Pablo Bay, Suisun Bay, and the river stations.
As the goals of this research project evolve over time, the sampling frequency and spatial coverage have changed. Since 1993 we have conducted monthly cruises along the entire Bay-Delta system as part of the Regional Monitoring Program for Water Quality in San Francisco Bay. Additional cruises in the South and Central Bay are conducted during spring and when rapid water quality changes associated with phytoplankton blooms are predicted. Learn more about what we sample in San Francisco Bay.
See the map and tables below for more detailed information about the sampling locations.
Current San Francisco Bay-Delta water quality sampling stations. Click on photo for a larger version. Current Station Table
Station geographic locations, beginning with riverine end of cruise track.
Station Location Latitude (degrees) Longitude (degrees) 657 Rio Vista 38.151667 -121.688333 649 Sacramento River 38.06 -121.8 2 Chain Island 38.063333 -121.851667 3 Pittsburg 38.051667 -121.88 4 Simmons Point 38.048333 -121.935 5 Middle Ground 38.06 -121.98 6 Roe Island 38.065 -122.035 7 Avon Pier 38.048333 -122.096667 8 Martinez 38.03 -122.151667 9 Benicia 38.056667 -122.185 10 Crockett 38.06 -122.208333 11 Mare Island 38.06 -122.266667 12 Pinole Shoal 38.051667 -122.311667 13 North of Pinole Point 38.028333 -122.37 14 Echo Buoy 38.006667 -122.405 15 Point San Pablo 37.973333 -122.436667 16 Charlie Buoy 37.916667 -122.446667 17 Raccoon Strait 37.878333 -122.421667 18 Point Blunt 37.846667 -122.421667 20 Blossom Rock 37.82 -122.393333 21 Bay Bridge 37.788333 -122.358333 22 Potrero Point 37.765 -122.358333 23 Hunters Point 37.728333 -122.336667 24 Candlestick Point 37.698333 -122.338333 25 Oyster Point 37.67 -122.325 26 San Bruno Shoal 37.636667 -122.313333 27 San Francisco Airport 37.618333 -122.291667 28 North of San Mateo Bridge 37.601667 -122.27 29 South of San Mateo Bridge 37.58 -122.245 29.5 Steinberger Slough 37.568333 -122.21833 30 Redwood Creek 37.555 -122.19 31 Coyote Hills 37.528333 -122.158333 32 Ravenswood Point 37.518333 -122.133333 33 Dumbarton Bridge 37.508333 -122.121667 34* Newark Slough 37.495 -122.098333 35 Mowry Slough 37.48 -122.078333 36 Calaveras Point 37.471667 -122.066667 * Sampling at this location for Station 34 began on 2/2/2016; for 1969 through 1/21/2016, the longitude degree was -122.093333.
Historic Station Table
Historic and non-standard stations geographic locations, temporal sampling range (first and last year data were collected), and mean low water depth.
Station Geographic Location Latitude (degrees) Longitude (degrees) Temporal Range Mean Low Water Depth (meters) 1 Winters Island 38.04 -121.84 1969-1978 6.5 12.5 Pinole Point 38.04 -122.315 1993-2001 6.7 19 Golden Gate 37.818333 -122.471667 1969-1985 91 24.5 South Bay 37.685075 -122.333328 1984 20 25.5 South Bay 37.6544 -122.319169 1984 13.2 26.5 South Bay 37.626324 -122.302245 1982-1984 8.7 27.5 South Bay 37.60956 -122.281678 1983 9 28.5 Geo Probe 37.596667 -122.235 1991-1995 15.7 30.5 South Bay 37.542166 -122.177256 1984 18 31.5 South Bay 37.522796 -122.145833 1982 12 33.5 South Bay 37.500692 -122.112337 1985 13 405 Reserve Fleet 2 38.048333 -122.123333 1999-2002 12.7 407 Reserve Fleet 4 38.071667 -122.093333 1999-2002 9.6 411 Garnet Sill 38.096667 -122.058333 1999-2002 7.3 650 Sacramento River 38.071667 -121.775 1984-1988 10 651 Sacramento River 38.078333 -121.763333 1980-1999 10 652 Towlands Landing 38.086667 -121.746667 1977-1984 7 653 Mid-Decker Island 38.105 -121.72 1984-2015 10.1 654 Sacramento River 38.105 -121.708333 1984 10 655 North of Three Mile Slough 38.121667 -121.701667 1980-1988 10.1 659 Old Sacramento River 38.178333 -121.666667 1977 10.1 662 Prospect Island 38.226667 -121.673333 1977 10.1 NOTE: From Aug 1999 through Jan 2002, Suisun Bay stations 405, 407 and 411 were sampled instead of standard channel stations 5, 6, and 7.
- Science
Below are other science pages associated with the Water Quality of San Francisco Bay project.
Water Quality of San Francisco Bay Research and Monitoring Project
Since 1969, the U.S. Geological Survey has maintained a research project in the San Francisco Bay-Delta system to measure and understand how estuarine systems and tidal river deltas function and change in response to hydro-climatic variability and human activities.Sampling Methods for the Water Quality of San Francisco Bay Project
The Water Quality of San Francisco Bay Research and Monitoring Project measures changes in water quality along the deep channel of the San Francisco Bay-Delta system using submersible sensors and discrete water samples. Learn more about how we collect and measure water-quality data.Research Vessel David H. Peterson
The Research Vessel David H. Peterson begain service with the U.S. Geological Survey in 2015. Named after a founder of the Water Quality of San Francisco Bay Research and Monitoring Project, this vessel is a high-tech scientific platform for estuarine research. Learn more about how the R/V David H. Peterson makes our research possible. - Data
Directly measured parameter data (depth, chlorophyll-a, dissolved oxygen, suspended particulate matter, extinction coefficient, salinity, temperature, nutrients) are available from the locations below:
USGS Measurements of Water Quality in San Francisco Bay (CA), 2016-2021 (ver. 4.0, March 2023)
The U.S. Geological Survey maintains a program of water-quality studies in San Francisco Bay (CA) that began in 1969. This U.S.G.S. Data Release is a continuation of the previously published 1969-2015 dataset (Cloern and Schraga, 2016; Schraga and Cloern, 2017), it will archive and make available all measurements from 2016 and thereafter. Each year, a data file containing the previous years data wPhytoplankton Species Composition, Abundance and Cell Size in San Francisco Bay: Microscopic Analyses of USGS Samples Collected 1992-2014
This Data Release makes available measurements of phytoplankton species composition, abundance and cell size made on samples collected in San Francisco Bay (CA) from April 1992 through March 2014. Phytoplankton samples were collected at 31 stations along a 145-km transect where the variability of salinity, temperature, turbidity and nutrient concentrations reflected a broad range of environmental - Web Tools
Directly measured parameter data (depth, chlorophyll-a, dissolved oxygen, suspended particulate matter, extinction coefficient, salinity, temperature, nutrients) are available from the locations below:
Data Query for the Water Quality of San Francisco Bay Project
Since 1969, USGS has collected water-quality data along the deep-channel longitudinal axis of the San Francisco Bay-Delta system at 37 fixed locations spaced 3-6 kilometers apart. The Water Quality of San Francisco Bay Data Query provides access to the entire dataset.