California Code, Government Code - GOV § 8132

The commission shall consist of seven members, the Director of Water Resources and six members appointed by the Governor, from California electors residing, owning property or engaged in business in the areas comprising the basins of the Truckee, Carson and Walker Rivers and Lake Tahoe as follows:

One from Sierra or Nevada County;  one from Placer County;  one from El Dorado County;  one from Alpine County;  one from Mono County;  and one member who resides at any place within the state, who shall represent the Lake Tahoe area.