Cal. Health & Safety Code § 116980

No person shall put any water closet, privy, cesspool or septic tank, or the carcass of any dead animal, or any offal of any kind, in, or upon the borders of, any stream, pond, lake, or reservoir from which water is drawn for the supply of any portion of the inhabitants of this state, in a manner that the drainage of the water closet, privy, cesspool or septic tank, or carcass, or offal may be taken up by or in the water.