Exhibit 21

Subsidiaries of the Registrant

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