20220608 10242000 1.0 TRUE i08_GroundwaterElevationSeasonal_Contours This layer depicts contours of estimated groundwater piezometric surfaces in the unconfined or uppermost semi-confined aquifers. Contours represent elevation above mean sea level (in feet, NAVD88), by year and season (fall or spring). The contour interval is 10 ft. California Department of Water Resources