Coast, Portola Valley, San Mateo County. We calculate high and low water here from an ocean tide model — accurate to about 5 cm on open coasts, considerably less in tidal flats and river mouths. This spot is officially monitored, but the responsible authority publishes no annual classification of the water quality.
Swimming spots in Portola Valley · San Mateo County · Swimming spots in the United States · Pacific Ocean · On the map