The Chino groundwater basin was adjudicated in 1978 by the San Bernardino County Superior Court and established the Chino Basin Watermaster comprised of three stakeholder groups as follows:
- Overlying Agricultural Pool Committee, representing dairymen, farmers, and the State of California;
- Overlying Non-Agricultural Pool Committee, representing area industries;
- Appropriative Pool Committee, representing local cities, public water districts, and private water companies.
The Water Company is party to the adjudication as an Appropriator with groundwater production rights within the basin.