California Code of Regulations
Title 23 - Waters
Division 5 - Prevention of Waste, Unreasonable Use or Diversion of Water (State Water Resources Control Board and Department of Water Resources)
Chapter 1 - Procedures
Section 4001 - Investigations

(a) Upon request of the board, or upon its own motion, or upon good cause shown by any interested person, and in furtherance of Water Code Sections 100, 101, 275, 304, and 305, the department shall investigate any misuse of water.

(b) Where it appears that the department could be a party to a misuse of water, or has a direct interest in the misuse by virtue of being a permit holder, or having a contractual or other interest in the specific case, which might conflict materially with its responsibilities under this chapter, the department shall suspend its investigation and notify the board. Upon any such notification, or upon its own motion or good cause shown by any interested person, the board shall determine whether the department has an interest in the misuse which would impair its ability to carry out its responsibilities under this chapter. If the board determines that such an interest exists, it shall request the department to suspend its investigation, or to continue the investigation under the board's direct supervision. If the department suspends its investigation, the board may continue the investigation.