Salt Ponds in San Francisco Bay

Salt Ponds in San Francisco Bay

In coming years, the shores of San Francisco Bay south of the San Mateo Bridge will begin to look a bit more like their former, pre-developed selves. The South Bay Salt Pond Restoration Project will be converting several clusters of salt evaporation ponds, pictured in vivid color in this Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) image from October 6, 2003, back into the tidal marshes, mudflats and other wetland ecosystems that pre-date human development of the area.

In the scene, ponds that are deep blue are inundated with water, while lighter and bright blue suggests ponds that are in various stages of evaporation, leaving behind the desired salt. Vegetation is bright green, bare soil is pinkish orange, and developed surfaces like cities and roads are light purple.

Three areas will be converted in the project: the Eden Landing area, which occupies the right-hand side of the Bay south of the San Mateo Bridge (upper left) and north of the Alameda County Flood Control Canal (s-shaped arc); the Ravenswood Point Area on the left-hand side of the Bay north and south of the Dumbarton Bridge (just left of image center); and the Alviso area, which will encompass most of the very dark blue ponds in the southern end of the Bay.

Wetland restoration has numerous benefits. Healthy wetlands are a natural water-purifying system, and they support more than 50 percent of the federally listed threatened or endangered species. They act as spawning grounds and nurseries for marine animals, and they control both erosion and flooding. Finally, they are important parts of recreation and tourism economies across the country.

For more about this ambitious restoration project, please visit the South Bay Salt Pond Restoration Project Website.

This false-color composite was created by combining infrared, near infrared, and red wavelengths (ASTER bands 4, 3, and 2 respectively).

NASA image created by Jesse Allen, Earth Observatory, using data provided courtesy of NASA/GSFC/MITI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team