Exhibit 99.1


         Southwest Water Acquires Utility in Southeast Texas


    LOS ANGELES--(BUSINESS WIRE)--May 4, 2007--Southwest Water Company
(NASDAQ:SWWC) today announced that it has acquired Diamond Water
Company and Water Services, Inc., consisting of 14 water systems that
serve approximately 7500 residents northwest of San Antonio.

    "This acquisition extends our footprint in the high growth area
around San Antonio," said Mark A. Swatek, chief executive officer and
chairman of Southwest Water. "We look forward to serving our new
customers in this important market."

    Southwest Water Company provides a broad range of services
including water production, treatment and distribution; wastewater
collection and treatment; utility billing and collection; utility
infrastructure construction management; and public works services. The
company owns regulated public utilities and also serves cities,
utility districts and private companies under contract. More than two
million people from coast to coast depend on Southwest Water for
high-quality, reliable service. Additional information may be found on
the company's website: www.swwc.com.


    CONTACT: Southwest Water Company
             DeLise Keim, VP, Corp. Communications, (213) 929-1846
             www.swwc.com
             or
             PondelWilkinson Inc.
             Robert Jaffe, (310) 279-5969
             www.pondel.com