California Harbors and Navigation Code
A district may be organized pursuant to this part. A district may include any contiguous territory in one or more counties, contiguous to a navigable river or to any channel connected with a navigable river, but a municipal corporation shall not be divided in the formation of a district, and territory situated in a county in which there is located a duly organized and existing port district, created pursuant to Part IV of this division, may not be included. Territory situated within the boundaries of any port or harbor district, organized or designated and existing under the provisions of any city charter, shall not be included. Any territory, annexed to a municipal corporation, which is in a district, becomes a part of the district.
Whenever the formation of a district is desired, a petition may be presented at a regular meeting of the board of supervisors of each county in which is located any portion of land within the proposed district. The petition may consist of any number of instruments and shall be signed by not less than five per cent of the registered voters residing within the district, who voted at the last preceding general election at which a Governor was elected. The original petition need not be filed with the board of supervisors of each county, but a certified copy of the original shall be filed.
The provisions of Chapters I and II of Division I of the District Organization Act shall govern and control the proceedings for the filing and hearing of the petition and the proceedings for final hearing of the petition and the formation of the district. The "supervising authority" as used in the District Organization Act means the board of supervisors of each county in which is located any portion of land within the proposed district.
All proceedings necessary for the formation of the district, as provided in Chapters I and II of Division I of the District Organization Act, shall be had in each county in which is located any portion of land within the proposed district. Land lying within any county within the proposed district shall not be included unless a majority of the electors in that portion of the district within the county vote in favor thereof.