The order annexing the petitioning district shall describe the boundaries of the land to be annexed to the annexing district, and if such land adjoins any portion of the annexing district, the order shall also describe that portion of the boundary of the annexing district which coincides with the boundaries of the land annexed. For the purposes of the order the board may cause a survey to be made of such portions of the boundaries as it deems necessary.
Ca. Water Code § 75974