Spring 1961 hydraulic head in the lower pumped zone of California's Central Valley (from Williamson and others, 1989)
This digital dataset defines the spring 1961 hydraulic head in the lower pumped zone of California's Central 
Valley.  It was used to initiate the water-level altitudes for the lower zones of the transient hydrologic model of 
the Central Valley flow system. The Central Valley encompasses an approximate 50,000 …