Exhibit 21

Subsidiaries of the Registrant

Subsidiary Name/Business Name		State of Incorporation
California Water Service Company		California
CWS Utility Services		California
New Mexico Water Service Company		New Mexico
Washington Water Service Company		Washington
Hawaii Water Service Company Inc.		Hawaii

The Registrant, California Water Service Group, and each of its subsidiaries operate in one business segment, the supply and distribution of water and providing water-related services.