Cal. Water Code § 12616

The department may conduct investigations of the water resources of the State, formulate plans for the control, conservation, protection, and utilization of such water resources, including solutions for the water problems of each portion of the State as deemed expedient and economically feasible, and may render reports thereon. In conducting such investigations and formulating such plans, the department may conduct investigations and surveys to determine the availability, usability, extents, and boundaries of underground basins.