California Seafloor and Coastal Mapping Program

Science Center Objects

A Foundation for Characterizing Hazards, Monitoring Change, and Managing Resources

A sea star with lots of legs on a sandy bottom of the sea.

Photograph of the seafloor off the California coast showing coarse sand, shells, and a sunflower sea star. It was taken during a "ground-truthing" survey off of Salt Point, California, in support of the CSCMP.

The California Seafloor and Coastal Mapping Program (CSCMP) is a collaborative effort of Federal, state, academic, and private-sector partners to create a comprehensive baseline map series and data sets that describe seafloor morphology, habitats, geology, and environments along the California coast. These products provide a framework for scientific research, as well as critical information to planners and decision-makers who oversee the management of resources and mitigation of risks of hazards in the coastal ocean.

NOAA is pleased to be partnering in this integrated ocean and coastal mapping project. By working with partners from across Federal, state, academic, and private sectors, we are able to combine data resources and maximize our efficiency in applying a "map once, use many times" approach that benefits all. – Rear Admiral Gerd F. Glang, Director NOAA’s Office of Coast Survey

CSCMP maps and data sets are created through the integration, interpretation, and visualization of many data types, including swath sonar and acoustic backscatter, seafloor video and photography, high-resolution seismic reflection profiles, and bottom sediment samples.

Virtual fly-through over the seafloor of Central California near San Francisco as if the water was drained from the ocean. The seafloor is colored for depth, with reds and oranges representing shallower regions and dark blues and purples representing deeper regions. Credit: Peter Dartnell, USGS

Each CMHRP map publication includes nine or more sheets, a pamphlet, and a digital data catalog. To date, 25 map sets have been published, covering 30% of California’s mainland coast. An important part of this effort is the online release of all project data, including large geospatial digital files and associated web services for users to create their own maps or engage in further investigations of the seafloor.

A bottomfish with small, bright spots lazily swims over a rocky seafloor among a few small pieces of kelp.

Digital still photograph offshore of Half Moon Bay, California, showing a kelp greenling, encrusting sponges, red algae, and cup coral in mixed gravel, cobbles, and rugose rock outcrop with scattered shells at a depth of 9 meters.

Computer simulation that shows water depth of a large bay, deeper water highlighted by darker colors.

Example of one of the sheets from the California map series. The USGS is a leader in creating CSCMP maps.

The maps and mapping data have a large range of applications. For example, the seamless Offshore and Onshore Geology and Geomorphology maps show and describe structural and geomorphic features critical to earthquake and landslide hazard assessments. Offshore fault locations and slip rates are being incorporated into the community fault model for northern California and used as the basis for earthquake rupture forecasts and ground motion prediction. Bathymetric data (measurements of the depth of the seafloor) are being incorporated into the Coastal Storm Modeling System (CoSMoS) to predict storm-induced coastal flooding, erosion, and cliff failures for northern California. In addition, maps of offshore sediment thickness are being used to develop Coastal Regional Sediment Management Plans along the California coast.

Illustration showing the location of the San Andreas Fault with underwater landslides identified nearby.

Geology and geomorphology offshore Fort Ross, showing slope failures along the San Andreas Fault.

Underwater photograph of jellyfish floating, they appear to be glowing.

This photograph of the seafloor off the California coast also shows jellyfish in the water column. This photograph was collected as part of the CSCMP.

The California Seafloor Mapping Program Video and Photograph Portal contains videos and photos of seafloor observations for all of California State Waters. These seafloor "ground-truthing" data were collected as a critical database to support development of derivative habitat and geologic maps. In Santa Barbara Channel, these data also contributed to maps showing predicted distribution of sea stars, sea pens, and cup coral. This observational database is now a stand-alone product being utilized by resource managers, outside researchers, and the public.

The view of a computer browser window of a web site, with a map of the western United States and sections of coastline outlined.

Screen capture of the California Seafloor Mapping Program Imagery home page.

Colored shaded-relief bathymetry map of Monterey Canyon and Vicinity, California

Colored shaded seafloor map of Monterey Canyon and vicinity, generated using a variety of sonar available through the California Seafloor and Coastal Mapping Program. The colors show depth. Reds and oranges indicate shallower areas, blues and purples show deeper areas. Credit: Peter Dartnell, USGS.


The CSCMP will continue to publish high-quality interpretive maps and data for California State Waters. The program will provide data and publications through easy-to-use web interfaces appropriate for a large and diverse user group. Public outreach will remain a priority as we strive to keep our science and science products relevant for the next generation.