Exhibit 99.1

		NEWS RELEASE CALIFORNIA WATER SERVICE GROUP

1720 North First Street
San Jose, CA 95112-4598

July 29, 2009
For Immediate Release

Contact:		Marty Kropelnicki (408) 367-8200 (analysts) Shannon Dean (310) 257-1435 (media)

CAL WATER ANNOUNCES RESULTS FOR THE 2ND QUARTER OF 2009

     SAN JOSE, CA — California Water Service Group (NYSE : CWT) today announced net income of $12.1 million, up 20% from $10.1 million in the second quarter of 2008, and earnings per common share (EPS) of $0.58, an increase of 21% over EPS of $0.48 in the same period last year.

     Revenues increased by $11.1 million, or 11%, to $116.7 million, with rate increases adding $19.2 million and water usage by new customers adding $3.4 million. These increases were offset by a decrease in water usage by existing customers and other charges totaling $11.1 million. The combined net effect of the water revenue adjustment mechanism (WRAM) and modified cost balancing account (MCBA) was a $0.4 million decrease in revenue. The WRAM is a ratemaking mechanism that decouples water sales from revenues and the MCBA is an account that allows Cal

Water to track and recover or refund changes in water production costs.

     Total operating expenses for the second quarter of 2009 increased by $9.6 million to $100.7 million. Water production costs increased by $1.4 million due to higher power costs and wholesale water rates. Administrative costs increased $5.6 million, due primarily to increases in pension, health, and legal expenses. Other operations expenses increased $1.6 million to $14.3 million, as a result of increases in costs of pumping and distributing water.

     Fewer water system repairs resulted in a $0.6 million decrease in maintenance expense, which was $4.3 million for the quarter. Depreciation expense increased $1.0 million to $10.3 million as a result of increases in capital expenditures. Taxes other than income increased $0.4 million to $3.9 million.

     Other income, net of income taxes, increased $1.1 million to $1.5 million. Interest expense increased $0.6 million to $5.3 million due to a new debt offering in April 2009.

     For the twelve months ended June 30, 2009, net income was $44.0 million and dilutive earnings per share were $2.11, compared to net income of $32.2 million and dilutive earnings per share of $1.55 for the same period in the prior year. Revenues for the trailing twelve months were $435.1 million, compared to $378.2 million for the same period last year.

     “The most important factor in our financial performance continues to be our ability to recover prudently incurred costs in rates, and our second quarter results were positively affected

by our approved rates in the 2007 General Rate Case filing,” said President and Chief Executive Officer Peter C. Nelson.

     “We also believe that the WRAM and MCBA are working effectively to facilitate water conservation and efficiency programs,” Nelson said.

     Rate-Related Matters

     On July 2, 2009, Cal Water filed a General Rate Case with the California Public Utility Commission for all California operations, beginning an 18-month review process. The filing requests an additional $70.6 million in 2011, followed by increases of $24.8 million in 2012 and 2013. The increased revenues are to cover expense increases and capital projects for 2011 through 2013. The Company cannot predict at this time the rate change the Commission will order in 2011.

     Interim rate increases, which are typically allowed in the second and third years following a General Rate Case, became effective on July 23, 2009 for 11 California Districts, which will add $9 million to annual revenues.

     Acquisitions and New Business

     In the second quarter of 2009, Cal Water received final approval from the California Public Utilities Commission on its acquisition of the Skyline County Water District, a 465-connection system adjacent to Cal Water’s Bear Gulch District.

     Other Information

     All stockholders and interested investors are invited to listen to the 2009 second quarter conference call on July 30, 2009, at 11:00 a.m. (EST), by dialing 1-866-871-4881 and keying in ID# 1369368. A replay of the call will be available from 2:00 p.m. (EST) July 30, 2009, through September 28, 2009, at 1-888-266-2081, ID# 1369368. The call, which will be hosted by President and CEO, Peter Nelson and Controller and Assistant Treasurer, Calvin L. Breed, will also be webcast under the investor relations tab at www.calwatergroup.com.

     California Water Service Group is the parent company of California Water Service Company, Washington Water Service Company, New Mexico Water Service Company, Hawaii Water Service Company, Inc., CWS Utility Services, and HWS Utility Services. Together these companies provide regulated and non-regulated water service to nearly 2 million people in California, Washington, New Mexico, and Hawaii. Group’s common stock trades on the New York Stock Exchange under the symbol “CWT”.

     This news release contains forward-looking statements within the meaning established by the Private Securities Litigation Reform Act of 1995 (“Act”). The forward-looking statements are intended to qualify under provisions of the federal securities laws for “safe harbor” treatment established by the Act. Forward-looking statements are based on currently available information, expectations, estimates, assumptions and projections, and management’s judgment about the Company, the water utility industry and general economic conditions. Such words as expects, intends, plans, believes, estimates, assumes, anticipates, projects, predicts, forecasts or variations of such words or similar expressions are intended to identify forward-looking statements. The forward-looking statements are not guarantees of future performance. They are subject to uncertainty and changes in circumstances. Actual results may vary materially from what is contained in a forward-looking statement. Factors that may cause a result different than expected or anticipated include, but are not limited to:

governmental and regulatory commissions’ decisions; changes in regulatory commissions’ policies and procedures; the timeliness of regulatory commissions’ actions concerning rate relief; new legislation; electric power interruptions; increases in suppliers’ prices and the availability of supplies including water and power; fluctuations in interest rates; changes in environmental compliance and water quality requirements; acquisitions and our ability to successfully integrate acquired companies; the ability to successfully implement business plans; changes in customer water use patterns; the impact of weather on water sales and operating results; access to sufficient capital on satisfactory terms; civil disturbances or terrorist threats or acts, or apprehension about the possible future occurrences of acts of this type; the involvement of the United States in war or other hostilities; restrictive covenants in or changes to the credit ratings on our current or future debt that could increase our financing costs or affect our ability to borrow, make payments on debt or pay dividends; and, other risks and unforeseen events. When considering forward-looking statements, you should keep in mind the cautionary statements included in this paragraph, as well as the annual 10-K, Quarterly 10-Q, and other reports filed from time-to-time with the Securities and Exchange Commission (SEC). The Company assumes no obligation to provide public updates of forward-looking statements.

     Additional information is available at our Web site at www.calwatergroup.com.

     Attachments (2).

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Source: California Water Service Group

CALIFORNIA WATER SERVICE GROUP
CONDENSED CONSOLIDATED BALANCE SHEETS
Unaudited

		June 30,				December 31
(In thousands, except per share data)		2009				2008
ASSETS
Utility plant:
Utility plant		$	1,638,356			$	1,583,079
Less accumulated depreciation and amortization			(492,989	)			(470,712	)
Net utility plant			1,145,367				1,112,367
Current assets:
Cash and cash equivalents			41,498				13,869
Receivables
Customers			26,613				22,786
Other			20,299				12,071
Unbilled revenue			20,273				13,112
Materials and supplies at average cost			5,244				5,070
Taxes, prepaid expense, and other assets			10,565				12,890
Total current assets			124,492				79,798
Other assets:
Regulatory assets			198,064				198,293
Goodwill			3,906				3,906
Other assets			31,411				23,743
Total other assets			233,381				225,942
		$	1,503,240			$	1,418,107
CAPITALIZATION AND LIABILITIES
Capitalization:
Common stock, $.01 par value		$	207			$	207
Additional paid-in capital			214,451				213,922
Retained earnings			191,098				188,820
Total common stockholders’ equity			405,756				402,949
Preferred stock			—				—
Long-term debt, less current maturities			383,500				287,498
Total capitalization			789,256				690,447
Current liabilities:
Current maturities of long-term debt			2,664				2,818
Accounts payable			48,344				41,772
Notes payable			12,000				40,000
Accrued expenses and other liabilities			38,202				38,606
Total current liabilities			101,210				123,196
Unamortized investment tax credits			2,392				2,392
Deferred income taxes, net			76,008				72,344
Regulatory liability and Other			83,282				83,312
Pension and postretirement benefits other than pensions			152,468				152,685
Advances for construction			179,566				176,163
Contributions in aid of construction			119,058				117,568
Commitments and contingencies
		$	1,503,240			$	1,418,107

CALIFORNIA WATER SERVICE GROUP
CONDENSED CONSOLIDATED STATEMENTS OF INCOME
Unaudited
(In thousands, except per share data)

For the Three-Months ended:

		June 30,				June 30,
		2009				2008
Operating revenue		$	116,667			$	105,581
Operating expenses:
Water production costs			41,702				40,349
Admistrative and General			19,385				13,835
Other operations			14,331				12,766
Maintenance			4,313				4,947
Depreciation and amortization			10,282				9,276
Income taxes			6,789				6,442
Property and other taxes			3,911				3,484
Total operating expenses			100,713				91,099
Net operating income			15,954				14,482
Other income and expenses:
Non-regulated revenue			3,098				1,696
Non-regulated expenses			(720	)			(1,132	)
Gain on sale of non-utility property			72				7
Less: income taxes on other income and expenses			(993	)			(219	)
			1,457				352
Interest expense:
Interest Expense			5,961				5,157
Less: capitalized interest			(640	)			(439	)
Net interest expense			5,321				4,718
Net income		$	12,090			$	10,116
Earnings per share
Basic		$	0.58			$	0.48
Diluted		$	0.58			$	0.48
Weighted average shares outstanding
Basic			20,745				20,717
Diluted			20,767				20,741
Dividends per share of common stock		$	0.2950			$	0.2925

CALIFORNIA WATER SERVICE GROUP
CONDENSED CONSOLIDATED STATEMENTS OF INCOME
Unaudited
(In thousands, except per share data)

For the Six-Months ended:

		June 30,				June 30,
		2009				2008
Operating revenue		$	203,280			$	178,502
Operating expenses:
Water production costs			70,570				65,707
Admistrative and General			38,247				27,253
Other operations			26,786				24,831
Maintenance			8,947				9,060
Depreciation and amortization			20,480				18,498
Income taxes			8,021				6,616
Property and other taxes			7,999				7,223
Total operating expenses			181,050				159,188
Net operating income			22,230				19,314
Other income and expenses:
Non-regulated revenue			5,979				4,601
Non-regulated expenses			(3,362	)			(4,168	)
Gain on sale of non-utility property			675				7
Less: income taxes on other income and expenses			(1,330	)			(170	)
			1,962				270
Interest expense:
Interest Expense			11,000				10,171
Less: capitalized interest			(1,319	)			(889	)
Net interest expense			9,681				9,282
Net income		$	14,511			$	10,302
Earnings per share
Basic		$	0.70			$	0.49
Diluted		$	0.70			$	0.49
Weighted average shares outstanding
Basic			20,738				20,702
Diluted			20,763				20,726
Dividends per share of common stock		$	0.5900			$	0.5850