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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

Form 10-K

Commission file No. 1-13883

CALIFORNIA WATER SERVICE GROUP
(Exact name of registrant as specified in its charter)

(408) 367-8200
(Registrant's Telephone Number, including Area Code)

         Securities registered pursuant to Section 12(b) of the Act:

         Securities registered pursuant to Section 12(g) of the Act: None

         Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. Yes ý    No o

         Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 of Section 15(d) of the Act. Yes o    No ý

         Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the Registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes ý    No o

         Indicate by check mark whether the registrant has submitted electronically and posted on its corporate Web site, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T (§ 232,405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files). Yes o    No ý

         Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K is not contained herein, and will not be contained, to the best of registrant's knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K. o

         Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See the definitions of "large accelerated filer," "accelerated filer" and "smaller reporting company" in Rule 12b-2 of the Exchange Act. (Check one):

         Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Act). Yes o    No ý

         The aggregate market value of the voting and non-voting common stock held by non-affiliates of the registrant was $781 million on June 30, 2011, the last business day of the registrant's most recently completed second fiscal quarter. The valuation is based on the closing price of the registrant's common stock as traded on the New York Stock Exchange.

         Common stock outstanding at February 22, 2012, 41,817,032 shares.

DOCUMENTS INCORPORATED BY REFERENCE

         Portions of the definitive proxy statement for the California Water Service Group 2012 Annual Meeting are incorporated by reference into Part III hereof.

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PART I

Item 1.    Business.

Forward-Looking Statements

        This annual report, including all documents incorporated by reference, contains forward-looking statements within the meaning established by the Private Securities Litigation Reform Act of 1995. Forward-looking statements in this annual report are based on currently available information, expectations, estimates, assumptions and projections, and our management's beliefs, assumptions, judgments and expectations about us, the water utility industry and general economic conditions. These statements are not statements of historical fact. When used in our documents, statements that are not historical in nature, including words like "expects," "intends," "plans," "believes," "may," "estimates," "assumes," "anticipates," "projects," "predicts," "forecasts," "should," "seeks," or variations of these words or similar expressions are intended to identify forward-looking statements. The forward-looking statements are not guarantees of future performance. They are based on numerous assumptions that we believe are reasonable, but they are open to a wide range of uncertainties and business risks. Consequently, actual results may vary materially from what is contained in a forward-looking statement.

        Factors which may cause actual results to be different than those expected or anticipated include, but are not limited to:

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governmental and regulatory commissions' decisions, including decisions on proper disposition of property;



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changes in regulatory commissions' policies and procedures;



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the timeliness of regulatory commissions' actions concerning rate relief;



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changes in the capital markets and access to sufficient capital on satisfactory terms;



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new legislation;



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changes in accounting valuations and estimates;



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changes in accounting treatment for regulated companies, including adoption of International Financial Reporting Standards, if required;



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electric power interruptions;



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increases in suppliers' prices and the availability of supplies including water and power;



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fluctuations in interest rates;



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changes in environmental compliance and water quality requirements;



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acquisitions and the ability to successfully integrate acquired companies;



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the ability to successfully implement business plans;



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civil disturbances or terrorist threats or acts, or apprehension about the possible future occurrences of acts of this type;



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the involvement of the United States in war or other hostilities;



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our ability to attract and retain qualified employees;



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labor relations matters as we negotiate with the unions;



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federal health care law changes that could result in increases to Company health care costs and additional income tax expenses in future years;

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changes in federal and state income tax regulations and treatment of such by regulatory commissions;



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implementation of new information technology systems;



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changes in operations that result in an impairment to acquisition goodwill;



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restrictive covenants in or changes to the credit ratings on current or future debt that could increase financing costs or affect the ability to borrow, make payments on debt, or pay dividends;



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general economic conditions, including changes in customer growth patterns and our ability to collect billed revenue from customers;



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changes in customer water use patterns and the effects of conservation;



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the impact of weather on water sales and operating results;



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the ability to satisfy requirements related to the Sarbanes-Oxley and Dodd-Frank Acts and other regulations on internal controls; and



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the risks set forth in "Risk Factors" included elsewhere in this annual report.

        In light of these risks, uncertainties and assumptions, investors are cautioned not to place undue reliance on forward-looking statements, which speak only as of the date of this annual report or as of the date of any document incorporated by reference in this annual report, as applicable. When considering forward-looking statements, investors should keep in mind the cautionary statements in this annual report and the documents incorporated by reference. We are not under any obligation, and we expressly disclaim any obligation, to update or alter any forward-looking statements, whether as a result of new information, future events or otherwise.

Overview

        California Water Service Group is a holding company incorporated in Delaware with six operating subsidiaries: California Water Service Company (Cal Water), New Mexico Water Service Company (New Mexico Water), Washington Water Service Company (Washington Water), Hawaii Water Service Company, Inc. (Hawaii Water), and CWS Utility Services and HWS Utility Services LLC (CWS Utility Services and HWS Utility Services LLC being referred to collectively in this annual report as Utility Services). Cal Water, New Mexico Water, Washington Water, and Hawaii Water are regulated public utilities. The regulated utility entities also provide some non-regulated services. Utility Services provides non-regulated services to private companies and municipalities. Cal Water was the original operating company and began operations in 1926.

        Our business is conducted through our operating subsidiaries. The bulk of the business consists of the production, purchase, storage, treatment, testing, distribution and sale of water for domestic, industrial, public and irrigation uses, and for fire protection. We also provide non-regulated water-related services under agreements with municipalities and other private companies. The non-regulated services include full water system operation, billing and meter reading services. Non-regulated operations also include the lease of communication antenna sites, lab services, and promotion of other non-regulated services. Earnings may be significantly affected by the sale of surplus real properties if and when they occur.

        During the year ended December 31, 2011, there were no significant changes in the kind of products produced or services rendered or those provided by our operating subsidiaries, or in the markets or methods of distribution.

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        Our mailing address and contact information is:

California Water Service Group
1720 North First Street
San Jose, California 95112-4598
telephone number: 408-367-8200
www.calwatergroup.com

        Annual reports on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K and amendments to these reports are available free of charge through our website. The reports are available on our website as soon as reasonably practicable after such reports are filed with the SEC.

Regulated Business

        California water operations are conducted by the Cal Water and CWS Utility Services entities, which provide service to approximately 471,900 customers in 83 California communities through 26 separate districts. Of these 26 districts, 24 districts are regulated water systems, which are subject to regulation by the California Public Utilities Commission (CPUC). Cal Water operates two leased water systems, the City of Hawthorne and the City of Commerce, which are governed through their respective city councils and are outside of the CPUC's jurisdiction. California water operations account for approximately 94% of our total customers and approximately 94% of our total consolidated operating revenue.

        Hawaii Water provides service to approximately 4,200 water and wastewater customers on the islands of Maui and Hawaii, including several large resorts and condominium complexes. Hawaii's regulated operations are subject to the jurisdiction of the Hawaii Public Utilities Commission. Hawaii Water accounts for less than 1% of our total customers and approximately 3% of our total operating revenue. HWS Utility Services LLC was organized in 2007 and began non-regulated operations in January 2008.

        Washington Water provides domestic water service to approximately 15,700 customers in the Tacoma and Olympia areas. Washington Water's utility operations are regulated by the Washington Utilities and Transportation Commission. Washington Water accounts for approximately 3% of our total customers and approximately 2% of our total consolidated operating revenue.

        New Mexico Water provides service to approximately 7,700 water and wastewater customers in the Belen, Los Lunas and Elephant Butte areas in New Mexico. New Mexico's regulated operations are subject to the jurisdiction of the New Mexico Public Regulation Commission. New Mexico Water accounts for approximately 2% of our total customers and approximately 1% of our total consolidated operating revenue.

        The state regulatory bodies governing our regulated operations are referred to as the Commissions in this annual report. Rates and operations for regulated customers are subject to the jurisdiction of the respective state's regulatory commission. The Commissions require that water and wastewater rates for each regulated district be independently determined based on the cost of service. The Commissions are expected to authorize rates sufficient to recover normal operating expenses and allow the utility to earn a fair and reasonable return on invested capital.

        We distribute water in accordance with accepted water utility methods. Where applicable, we hold franchises and permits in the cities and communities where we operate. The franchises and permits allow us to operate and maintain facilities in public streets and right- of-ways as necessary.

        We operate the City of Hawthorne and the City of Commerce water systems under lease agreements. In accordance with the lease agreements, we receive all revenues from operating the systems and are responsible for paying the operating costs. The revenues and expenses for leased water systems are included in operating revenues and expenses. Rates for the City of Hawthorne and City of

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Commerce water systems are established in accordance with operating agreements and are subject to ratification by the respective city councils. The terms of other operating agreements range from one-year to three-year periods with provisions for renewals.

        In February 2011, our lease agreement for the operation of the City of Hawthorne water system expired. At the end of the lease term, the City of Hawthorne credited Cal Water $6.5 million for net capital improvements that we made to the City of Hawthorne's water system. Following the expiration of the lease agreement, we continued to operate the City of Hawthorne's water system on a month-to-month basis until October 2011, when we entered into a new 15-year capital lease agreement to operate the City of Hawthorne water system. The system, which is located near the Hermosa-Redondo district, serves about half of Hawthorne's population. The new lease agreement required us to make an up-front $8.1 million lease deposit to the city that is being amortized over the lease term. Additionally, annual lease payments of $0.9 million are made to the city and shall be increased or decreased each year on July 1, by the same percentage that the rates charged to customers served by the water system increased or decreased, exclusive of pass-through increases or decreases in the cost of water, power, and city-imposed fees, compared to the rates in effect on July 1 of the prior year, provided, that in no event will the annual lease payment be less than $0.9 million. Under the lease we are responsible for all aspects of system operation and capital improvements, although title to the system and system improvements reside with the city. In exchange, we receive all revenue from the water system, which was $7.5 million, $7.5 million and $6.1 million in 2011, 2010, and 2009, respectively. At the end of the lease, the city is required to reimburse us for the unamortized value of capital improvements made during the term of the lease.

        In July 2003, an agreement was negotiated with the City of Commerce to lease and operate its water system. The lease requires us to pay $0.8 million per year in monthly installments and pay $200 per acre-foot for water usage exceeding 2,000 acre-feet per year plus a percentage of certain operational savings that may be realized. Under the lease agreement, we are responsible for all aspects of the system's operations. The city is responsible for capital expenditures, and title to the system and system improvements resides with the city. We bear the risks of operation and collection of amounts billed to customers. The agreement includes a procedure to request rate changes for cost changes outside of our control and other cost changes. In exchange, we receive all revenue from the system, which totaled $1.8 million in 2011 and 2010 and $1.7 million in 2009. The City of Commerce lease is a 15-year lease and expires in 2018.

        The City of Hawthorne and the City of Commerce leases revenues are governed through their respective city councils and are considered non-regulated because they are outside of the CPUC's jurisdiction. We report revenue and expenses for the City of Hawthorne and City of Commerce leases in operating revenues and operating expenses because we are entitled to retain all customer billings and are generally responsible for all operating expenses.

Non-Regulated Businesses

        Fees for non-regulated activities are based on contracts negotiated between the parties. Under other non-regulated contract arrangements, we operate municipally owned water systems, privately owned water systems, and recycled water distribution systems, but are not responsible for all operating costs. Non-regulated revenue received from water system operations is generally determined on a fee-per-customer basis.

        Non-regulated activities consist primarily of:

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operating water and waste water systems, which are owned by other entities;



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providing meter reading and billing services;



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leasing communication antenna sites on our properties;

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operating recycled water systems;



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providing lab services for water quality testing;



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billing of optional third-party insurance program to our residential customers;



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selling surplus property; and



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other services as requested by the client.

        The revenues and expenses for leased water systems are included in operating revenues and operating expenses. All other non-regulated revenues and expenses are reported below net operating income on the income statement. Due to the variety of services provided and activities being outside of our core business, the number of customers is not tracked for these non-regulated activities, except customers for the City of Hawthorne and the City of Commerce. Effective June 30, 2011, the CPUC adopted new rules surrounding provision of unregulated services using utility assets and employees. As a result, nearly all California unregulated activities are now considered "nontariffed products and services (NTPS)." The prescribed accounting for these NTPS is incremental cost allocation plus revenue sharing with rate payers. Non-regulated services determined to be "active activities" require a 10% revenue sharing and "passive activities" require a 30% revenue sharing. The amount of non-regulated revenues subject to revenue sharing is the total billed revenues less any authorized pass through costs. Some examples of CPUC authorized pass through costs are purchased water, purchased power, and pump taxes. All of the non-regulated services listed above, except property leases, are "active activities" subject to a 10% revenue sharing. Property leases are "passive activities" subject to a 30% revenue sharing. The 2011 revenue sharing was $1.5 million. Any significant change in revenue sharing will be reflected in adopted rates after the next general rate case and will be accompanied by a change from full-cost allocation to incremental-cost allocation.

        We provide operating and maintenance, meter reading and customer billing services for several municipalities in California. We also provide sewer and refuse billing services to several municipalities. Revenues for these services were $10.4 million, $10.4 million, and $12.4 million in 2011, 2010, and 2009, respectively.

        We lease antenna sites to telecommunication companies, which place equipment at various Company-owned sites. Lease revenues totaled $1.9 million, $2.2 million, and $2.0 million in 2011, 2010 and 2009, respectively. The antennas are used in cellular phone and personal communication applications. We continue to negotiate new leases for similar uses.

        In 2006, we started an Extended Service Protection program (ESP) in California covering certain repairs to residential customer's water line between the meter and the home. The non-regulated program was operated by CWS Utility Services. Typically the utility is responsible for servicing and maintaining the water line up to and including the meter. The home owner is responsible for the water line from the meter to the house. In late 2007, we contracted with Home Service USA to replace the ESP program with an insurance product. Home Service USA now provides water line protection insurance, sewer line protection insurance, and internal plumbing protection insurance to Cal Water's customers who request it. Cal Water includes charges for these optional non-tariffed services on its bills. Revenues for these services were $2.0 million, $2.0 million, and $1.7 million in 2011, 2010, and 2009, respectively. In September 2011 as part of a settlement with the Division of Ratepayer Advocates, we proposed to the CPUC a rate payer refund of $2.1 million relating to the ESP program sale proceeds as of December 31, 2011. The proposed settlement resolves the last open issue with the Division of Ratepayer Advocates regarding the revenue sharing with rate payers. The proposed settlement reduced 2011 operating revenues and was recorded as a regulatory liability on the balance sheet as of December 31, 2011.

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Operating Segment

        We operate in one reportable segment, the supply and distribution of water and providing water-related utility services.

Growth

        We intend to continue exploring opportunities to expand our regulated and non-regulated water and wastewater businesses in the western United States. The opportunities could include system acquisitions, lease arrangements similar to the City of Hawthorne and City of Commerce contracts, full service system operation and maintenance agreements, meter reading, billing contracts and other utility-related services. Management believes that a holding company structure facilitates providing non-regulated utility services, which are not subject to any Commission's jurisdiction.

Geographical Service Areas and Number of Customers at Year-end

        Our principal markets are users of water within our service areas. Most of the geographical service areas are regulated; however, the City of Hawthorne and City of Commerce are included due to similarities in structure and risk of operations. The approximate number of customers served in each district is as follows:

        Regulated Customers, City of Hawthorne and City of Commerce Customers at December 31, (rounded to the nearest hundred)

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Rates and Regulation

        The state regulatory commissions have plenary powers setting rates and operating standards. As such, state commission decisions significantly impact Cal Water's revenues, earnings, and cash flows. The amounts discussed herein are generally annual amounts, unless specifically stated, and the financial impact to recorded revenue is expected to occur over a 12-month period from the effective date of the decision. In California, water utilities are required to make several different types of filings. Most filings result in rate changes that remain in place until the next General Rate Case (GRC). As explained below, surcharges and surcredits to recover balancing and memorandum accounts as well as general rate case interim rate catch-up. Surcharges are temporary rate changes, which have specific time frames for recovery.

        GRCs, escalation rate increase filings, and offset filings change rates to amounts that will remain in effect until the next GRC. The CPUC follows a rate case plan, which requires Cal Water to file a GRC for each of its regulated operating districts every three years. In a GRC proceeding, the CPUC not only considers the utility's rate setting requests, but may also consider other issues that affect the utility's rates and operations. The CPUC is generally required to issue its GRC decision prior to the first day of the test year or authorize interim rates. In accordance with the rate case plan, the Commission issued a decision on Cal Water's 2009 general rate case filing in the fourth quarter of 2010 with rates effective on January 1, 2011. Cal Water expects to file its next GRC on July 2, 2012, which will be applicable to all of its California Districts. Any rate change as a result of that filing is expected to be effective on January 1, 2014.

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        Between GRC filings utilities may file escalation rate increases, which allow the utility to recover cost increases, primarily from inflation and incremental investment, during the second and third years of the rate case cycle. However, escalation rate increases are subject to a weather-normalized earnings test on a district-by-district basis. Under the earnings test, the CPUC may reduce the escalation rate increase if, in the most recent 12-month period, this earnings test reflects earnings in excess of authorized for that district.

        In addition, California water utilities are entitled to make offset filings. Offset filings may be filed to adjust revenues for construction projects authorized in GRCs when the plant is placed in service or for rate changes charged to the Company for purchased water, purchased power, and pump taxes (referred to as "offsettable expenses"). Such rate changes approved in offset filings remain in effect until the next GRC is approved.

        The Water Revenue Adjustment Mechanism (WRAM) and Modified Cost Balancing Account (MCBA) are required by the CPUC to remove the disincentive for Cal Water to promote lower water consumption levels with water conservation programs. In order to maintain revenue neutrality, the CPUC de-coupled Cal Water's revenue requirement from ratepayer usage with the WRAM/MCBA. Under the WRAM/MCBA, Cal Water recovers the full quantity revenue amounts authorized by the CPUC by using advice letter filings for any unbilled quantity revenue amounts or refunds for overcollection, regardless of customer usage volumes.

        Surcharges and surcredits advice letters to amortize balances in the WRAM and MCBA accounts are filed between February and April of each year based on the district balances for the last calendar year. Based on current CPUC interpretations, surcharges are amortized between 12 and 36 months. In the event the combined WRAM and MCBA balance for a district is less than 2.5% of district authorized revenue, the amount will not be amortized at that time. The WRAM and MCBA amounts are cumulative, so if they are not amortized in a given calendar year, the balance will be carried forward and included with the following year balance.

Application to Resolve Commission's Procedures for WRAM amortization

        Cal Water, along with four other investor-owned water utilities filed a joint application to change the amortization periods to 24 months or less. Cal Water anticipated, based upon hearings and discussions with the Department of Rate Payer Advocates, that a final decision would have been reached by mid-year 2011 to recover the WRAM and MCBA accounts within 24 months or less. In June 2011, the Administrative Law Judge (ALJ) after numerous pre-hearing conferences, established a schedule to resolve the recovery period with the expectation of a final Commission Decision on December 15, 2011. As of the date of this filing, no decision has been reached by the CPUC and Cal Water determined that the revenue and associated operating costs should be adjusted in the fourth quarter of 2011 to reflect balances that currently will not be collected within 24 months. The impact was to exclude WRAM revenues of $12.9 million, other operating expenses of $10.5 million, and net operating income of $2.4 million before income taxes as of December 31, 2011. The recording of the excluded revenue and associated costs on the consolidated statements of income will depend upon the final decision by the CPUC, now anticipated to be in 2012. If a decision is not reached to reduce the amortization period, the recovery of this amount and future WRAM amounts will be assessed at the end of each reporting period. Recognition of revenue and the associated costs is limited to those expected to be recovered from customers within 24 months. If a refund is due ratepayers, it will be recorded during the reporting period the overcollection occurs, regardless of the refund period authorized by the Commission.

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Remaining Balances from Previously Authorized Balancing Accounts Recoveries/Refunds

        Prior to the adoption of the MCBA on July 1, 2008, the CPUC required incremental cost balancing accounts (ICBA) memorandum and balancing accounts which had a remaining balance of approximately $1.4 million as of December 31, 2010. In CPUC decision 10-12-017, Cal Water was authorized to file to recover its remaining balances in these accounts. This filing occurred in the first quarter of 2011 with an effective date of April 1, 2011. The refunds and billings started at the end of calendar year 2010 and will be completed during calendar year 2012. As of December 31, 2011 the ICBA net receivable balance was $0.6 million.

2011 Regulatory Activity

California Cost of Capital Applications

        Cal Water along with the three other large water utilities in California filed an application with the CPUC in May of 2011 to review its cost of capital for 2012 through 2014. The Company and the other applicant companies proposed a settlement with the Division of Ratepayer Advocates which is now pending before the CPUC. The settlement would have the CPUC adopt a 9.99% return on equity and 53.4% equity capital structure for rate setting purposes. It would also continue the Water Cost of Capital Mechanism (WCCM), which would adjust allowed equity returns if there is a large change in the Moody AA utility bond index. The parties anticipate a favorable decision approving the settlement in the first or second quarter of 2012. Because this proceeding was scheduled to set the authorized rate of return for the Company's investment starting on January 1, 2012 and a decision had not been issued, the CPUC required Cal Water to file an advice letter to establish a Cost of Capital interim rate memorandum account. This will serve as a mechanism to true up rates to reflect the final decision in this proceeding.

2009 California GRC Decision

        On July 2, 2009, Cal Water filed its 2009 GRC application covering all district and general office revenue requirements. The GRC application requested an increase of $70.6 million or 16.75% in rates for 2011, $24.8 million or 5.04% in rates for 2012 and $24.8 million or 4.79% in rates for 2013. On December 2, 2010, the CPUC issued decision 10-12-017, which approved a settlement between Cal Water, the Division of Ratepayer Advocates, and several intervenors representing the interests of individual district customers. This decision allows for revenue increases of $25.4 million or 5.6% in 2011. Cal Water is also allowed to file for increases of $9.6 million or 2.0% for 2012, and $9.0 million or 2.0% for 2013 subject to adjustment for indexed inflation and contingent upon passing a weather normalized earnings test. This decision also allows for offset increases after construction of 77 large capital projects in various operating districts.

        In addition, the Company was authorized to make a deviation from its escalation expense and exclude employee health care, retiree health insurance, and conservation expenses from it escalation filings in 2012 and 2013. Instead for these three significant expense items, the CPUC has enumerated fixed three-year budgets for these expenses. It is anticipated that the budgets for these areas will more closely align with the actual expenses now that this change has been initiated.

        The CPUC also authorized a Pension Balancing Account to track the difference between authorized pension contributions included in rates and the costs actually incurred. It is anticipated that this account will allow Cal Water to reduce some of the volatility it experiences in regard to the recovery of these costs from customers.

        The Company was also authorized to combine the rates and tariffs of the South San Francisco and the Mid Peninsula Districts, located on the San Francisco peninsula, into a single ratemaking area in

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2011. This new ratemaking area is known as the Bayshore District. Previously, the two separate districts had been operated out of a combined location.

        Due to the transition between a phased rate case and a total company filing, the CPUC delayed the rate cases of 16 Cal Water districts. However, to compensate for this delay, the CPUC authorized interim rates from the authorized effective date under the old rate case plan. The difference between revenue requirements that were effective in the interim period and those calculated based on a final determination in the 2009 general rate case filing totaled $6.7 million and is being recovered as customer surcharges over a three-year period. During 2011, $3.8 million was billed and recorded as revenue. The remaining balance of $2.9 million is expected to be recovered over the next two years and will be recorded as revenue when billed. Over-collected amounts from ratepayers will be recorded as regulatory liability during the reporting period in which it occurs. As of December 31, 2011, the over-collected amount of $0.4 million was recorded as a regulatory liability.

Low Income Ratepayer Assistance Program

        Cal Water currently administers a Low Income Ratepayer Assistance Program (LIRA) in accordance with decision D.06-11-053. This program provides qualifying low income customers with a 50% discount on their service charge (up to a maximum of $12 per month). It imposes a surcharge on non-qualifying customers of $0.01 per hundred cubic feet of monthly water consumption for metered customers and between $0.24 and $0.41 per flat rate service per month. Due to a successful enrollment of over 49,000 customers, this account had accumulated an under collection of approximately $5.5 million as of December 31, 2011, and is recorded in non-current regulatory assets. In July 2010, Cal Water filed an advice letter to adjust the timing of collection for the surcharge in order to resolve this under collection situation. The CPUC rejected this filing and determined that this surcharge could only be adjusted during a GRC. In early 2012, Cal Water filed a petition to modify D.06-11-053 to 1) increase surcharges to balance program expenses and revenues, 2) amortize the current balance in the program, and 3) establish an annual adjustment mechanism to reduce the potential or large balances in the future.

2010 Ka'anapali (Hawaii) GRC Filing

        On December 30, 2010, Hawaii Water filed its 2010 GRC application for the Ka'anapali Service Area. The Hawaii Public Utilities Commission (HPUC) requires a separate rate application for all service areas and uses a limited future test year. The Ka'anapali GRC requested additional revenue of $1.5 million or an increase of 38.2% over the prior year. HWSC and the Consumer Advocate of the HPUC reached a tentative settlement on this rate increase. On January 11, 2012, the HPUC issued a Decision and Order ("D&O") approving the stipulated settlement. This will result in a $1.2 million or a 30.8% increase in revenue that will be effective in early 2012.

2011 Pukalani (Hawaii) GRC Filing

        In August 2011, HWSC filed a general rate case for the Pukalani wastewater system requesting $1.3 million in additional annual revenues. HWSC expects to enter into settlement negotiations with the Consumer Advocate in early 2012. At this time, HWSC cannot determine timing or final amount of rate relief this filing will generate.

2011 Washington Water GRC Filing

        In 2011, Washington Water filed a general rate case for its operation. It requested a $1.7 million, or 21.8%, increase in revenue. On January 26, 2012, the WUTC approved a $1.6 million, or 20.0%, increase effective in the first quarter of 2012.

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Federal Income Tax Bonus Depreciation

        In 2011, Cal Water filed for and received approval to track the benefits from federal income tax accelerated depreciation in a memorandum account due to the Tax Relief, Unemployment Insurance Reauthorization, and Job Creation Act of 2010. Additional federal income tax deductions for assets placed in service after September 8, 2010 and before December 31, 2011 was $6.6 million for 2010 and estimated at $10.5 million for 2011. The CPUC will determine the disposition of amounts recorded in the memorandum account in Cal Water's next GRC.

Request for MTBE regulatory treatment

        The CPUC in its Decision (D.) 10-10-018 issued rules for treating contamination proceeds generally. Subsequently, the CPUC's D.11-03-043 resolved Cal Water's separate application for treatment of MTBE proceeds by ordering continued tracking of the proceeds and expenditures until litigation and remediation are both complete. The new rules allow Cal Water to file an advice letter to move proceeds from this tracking account into Contributions in Aid of Construction ("CIAC") when remediation or replacement projects are complete. Cal Water has completed several such projects totaling $16.7 million. While the advice letters have not been filed for some of these projects, Cal Water believes it is probable the CPUC will treat the invested amounts as CIAC when the advice letters are filed. The Company has reclassified $16.7 million from regulatory and other liabilities to CIAC during 2011. Project costs totaling $9.1 million were treated as CIAC in setting rates in the 2009 General Rate Case effective January 1, 2011, so there is no rate impact for this reclassification. For projects not identified in the 2009 General Rate Case, as projects to remediate or replace MTBE-contaminated plant are completed, the Company will book a reclassification from other long-term liabilities to CIAC and adjust rate base during the next GRC.

        The CPUC's adopted rules would require all contamination proceeds to be used first to pay transactional expenses, then to make ratepayers whole for costs to ensure the water system complies with the CPUC's water quality standards. The rules allow for a risk-based consideration of proceeds which exceed the costs of the remediation described above and may result in some sharing of excess, or "net" proceeds. Because treatment or replacement of Cal Water's MTBE contaminated wells will occur over a number of years, and because litigation continues with remaining defendants, a final disposition of Cal Water's memorandum account will occur at an unknown future date. Cal Water will continue to monitor proceeds and remediation and will report to the CPUC in its next GRC. Because of uncertainty surrounding eventual litigation proceeds, remediation capital and operating costs, and the eventual ratemaking treatment of "net proceeds" as defined by the CPUC, Cal Water cannot predict the future disposition of its partial MTBE settlement proceeds at this time.

Service Line Insurance Billing

        As a consequence of D.07-12-055 which resolved Cal Water's 2006 GRC, Cal Water was required to demonstrate that its non-regulated Extended Service Protection (ESP) business or its successor complies with CPUC rules. Cal Water made an administrative compliance filing in 2008 which was rejected. Cal Water subsequently filed A.08-05-019 requesting Commission confirmation that the interaction between Cal Water, CWS Utility Services, and Home Service USA complied with all applicable rules. During the proceeding, the CPUC established a memorandum account to record Cal Water's revenues and expenses related to the non-regulated service line insurance business. The application is being processed in 2011 and 2012 after the CPUC adopted comprehensive rules for the relationships between regulated utilities and their unregulated affiliates and the rules for offering non-tariffed products and services. These rules went into effect on June 30, 2011 as a result of D.10-10-019. The CPUC's ratepayer advocate testified that Cal Water's customers should receive some of the proceeds from the sale of the non-regulated ESP business as well as other program revenues. While Cal Water challenged these claims and presented its own testimony, the parties were able to

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reach a settlement on all issues in the case. The proposed settlement, which was filed in October 2011, describes the accounting and revenue sharing applicable to the non-regulated service line business after June 30, 2011 and proposes a monetary settlement of $2.1 million to ratepayers to resolve all issues related to non-regulated service line business activity from 2007 through June 30, 2011. The settlement is still subject to approval by the CPUC. Cal Water anticipates that the CPUC will approve the settlement in the second quarter of 2012. A $2.1 million regulatory liability and reduction to revenues was recorded during the third quarter of 2011. The amount would be refunded on ratepayer bills over a twelve month period.

2011 Expense Offset filings

        In 2011, Cal Water filed advice letters to offset increased purchased water and pump tax rates in nine of its regulated districts totaling $25.4 million in annual revenue. Expense offsets are dollar-for-dollar increases in revenue to match increased expenses and interact with the WRAM and MCBA mechanisms so that net operating income is not affected by an offset increase.

        In the future, Cal Water plans to file advice letters to offset expected increases in purchased water and pump tax charges in some districts. Cal Water cannot predict the exact timing or dollar amount of the changes.

2011 Ratebase Offset filings

        In 2011, Cal Water filed an advice letter to offset an infrastructure improvement project in its Westlake District totaling $1.4 million in annual revenue. Companies are allowed to file rate base offsets to increase revenues for construction projects authorized in GRCs when the plant is placed in service. The project for this filing was authorized in the 2009 GRC. The remaining $71.7 million of advice letter projects are scheduled to be completed during 2012 and 2013.

Water Supply

        Our source of supply varies among our operating districts. Certain districts obtain all of their supply from wells; some districts purchase all of their supply from wholesale suppliers; and other districts obtain supply from a combination of wells and wholesale suppliers. A small portion of supply comes from surface sources and is processed through Company-owned water treatment plants. During 2011, an estimated 120 billion gallons of water was produced to meet customer demand, down 1.3% from the estimated 122 billion gallons produced in 2010. The 2011 average daily water production was approximately 330 million gallons. Historically, approximately half of the Company's water supply is purchased from wholesale suppliers with the balance pumped from wells. In 2011, approximately 48 percent of the Company's supply was obtained from wells, 47 percent was purchased from wholesale suppliers and 5 percent was obtained from surface supplies. By comparison, in 2010, the average daily water production was approximately 334 million gallons. Well water is generally less expensive and the Company strives to maximize the use of its well sources in districts where there is an option between well or purchased supply sources.

        In California, we obtain our water supply from wells, surface runoff or diversion, and by purchase from public agencies and other wholesale suppliers. Our water supply has been adequate to meet customer demand; however, during periods of drought, some districts have experienced mandatory water rationing. California's rainy season usually begins in November and continues through March with the most rain typically falling in December, January and February. During winter months, reservoirs and underground aquifers are replenished by rainfall. Snow accumulated in the mountains provides an additional water source when spring and summer temperatures melt the snowpack, producing runoff into streams and reservoirs, and also replenishing underground aquifers. There are six California water treatment plants located in the Bakersfield, Bear Gulch, Kernville, Oroville and

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Redwood Valley districts. Water for operation of the Bakersfield plants, with a combined capacity of 28 million gallons per day, is drawn from the Kern River under a long-term contract with the City of Bakersfield. The other four plants have a combined capacity of 18 million gallons per day.

        Washington and Hawaii receive rain in all seasons with the majority falling during winter months. Washington Water and Hawaii Water draw all their water supply by pumping from wells. New Mexico Water's rainfall normally occurs in all seasons, but is heaviest in the summer monsoon season. New Mexico Water pumps all of its water supply from wells based on its water rights.

        The following table shows the estimated quantity of water purchased and the percentage of purchased water to total water production in each California operating district that purchased water in 2011. Other than noted below, all other districts receive 100% of their water supply from wells.

        The Bear Gulch district obtains a portion of its water supply from surface runoff from the local watershed. The Oroville and Redwood Valley districts in the Sacramento Valley and the Bakersfield

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and Kern River Valley districts in the San Joaquin Valley purchase water from a surface supply. Surface sources are processed through our water treatment plants before being delivered to the distribution system. The Bakersfield district also purchases treated water as a component of its water supply.

        The Chico, Marysville, Dixon, and Willows districts in the Sacramento Valley, the Salinas and King City districts in the Salinas Valley, and the Selma and Visalia districts in the San Joaquin Valley obtain their entire supply from wells. In the Salinas district, which solely depends upon ground water, several wells were taken out of service in the last four years, primarily due to poor water quality. Treatment systems have been installed on some of these wells to meet customer demand. Management believes water supply issues in the Salinas district will be adequately resolved in the future by seeking additional sources or additional treatment.

        Purchases for the Los Altos, Livermore, Oroville, Redwood Valley, Stockton, and Bakersfield districts are pursuant to long-term contracts expiring on various dates after 2011. The water supplies purchased for the Dominguez, East Los Angeles, Hermosa-Redondo, Palos Verdes, and Westlake districts as well as the Hawthorne and Commerce systems are provided by public agencies pursuant to a statutory obligation of continued non- preferential service to purveyors within the agencies' boundaries. Purchases for the Bayshore and Bear Gulch districts are in accordance with long-term contracts with the San Francisco Public Utilities Commission (SFPUC) until June 30, 2034.

        Management anticipates water supply contracts will be renewed as they expire though the price of wholesale water purchases is subject to pricing changes imposed by the various wholesalers.

        Shown below are wholesaler price rates and increases that became effective in 2011 and estimated wholesaler price rates and percent changes for 2012. In 2011, several districts experienced significant purchased water cost increases resulting in a significant impact in the 2011 MCBA balance and the filing of several purchased water offsets.

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        We work with all local suppliers and agencies responsible for water supply to insure adequate, long-term supply for each system.

        See Item 7, "Management's Discussion and Analysis of Financial Condition and Results of Operations—Water Supply" concerning more information on adequacy of supplies.

Seasonal Fluctuations

        In California, our customers' consumption pattern of water varies with the weather, in terms of rainfall and temperature. In the WRAM and MCBA design, the CPUC considers the historical pattern in determining the adopted sales and production costs. With a majority of our sales being subject to the WRAM and production costs being covered by the MCBA, variations from the adopted pattern has been minimized. However, cash flows from operations and short-term borrowings on our credit facilities are significantly impacted by seasonal fluctuations including recovery of the WRAM and MCBA.

        Our water business is seasonal in nature. Weather conditions can have a material effect on customer usage. Customer demand for water generally is lower during the cooler and rainy, winter months. Demand increases in the spring when warmer weather returns and the rains end, and customer use more water for outdoor purposes, such as landscape irrigation. Warm temperatures during the generally dry summer months result in increased demand. Water usage declines during the fall as temperatures decrease and the rainy season begins. During years in which precipitation is especially heavy or extends beyond the spring into the early summer, customer demand can decrease from historic normal levels, generally due to reduced outdoor water usage. Likewise, an early start to the rainy season during the fall can cause a decline in customer usage. As a result, seasonality of water usage has a significant impact on our cash flows from operations and borrowing on our short-term facilities.

Utility Plant Construction

        We have continually extended, enlarged, and replaced our facilities as required to meet increasing demands and to maintain the water systems. We obtain construction financing using funds from operations, short-term bank borrowings, long-term financing, advances for construction and contributions in aid of construction that are funded by developers. Advances for construction are cash deposits from developers for construction of water facilities or water facilities deeded from developers. These advances are generally refundable without interest over a period of 40 years in equal annual payment amounts. Contributions in aid of construction consist of nonrefundable cash deposits or facilities transferred from developers, primarily for fire protection and relocation projects. We cannot control the amount received from developers. This amount fluctuates from year-to-year as the level of construction activity carried on by developers varies. This activity is impacted by the demand for housing, commercial development, and general business conditions, including interest rates.

        See Item 7, "Management's Discussion and Analysis of Financial Condition and Results of Operations—Liquidity and Capital Resources" for additional information.

Sale of Surplus Real Properties

        When properties are no longer used and useful for public utility purposes, we are no longer allowed to earn a return on our investment in the property in the regulated business. The surplus property is transferred out of the regulated operations. From time to time, some properties have been sold or offered for sale. As these sales are subject to local real estate market conditions and can take several months or years to close, income from the sale of surplus properties may or may not be consistent from year-to-year.

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California Energy Situation

        We continue to use power efficiently to minimize the power expenses passed on to our customers, and maintain backup power systems to continue water service to our customers if the power companies' supplies are interrupted. Many of our well sites are equipped with emergency electric generators designed to produce electricity to keep the wells operating during power outages. Storage tanks also provide customers with water during blackout periods.

Impact of Climate Change Legislation

        Our operations depend on power provided by other public utilities and, in emergencies, power generated by our portable and fixed generators. If future legislation limits emissions from the power generation process, our cost of power may increase. Any increase in the cost of power will be passed along to our California rate payers through the MCBA or included in our cost of service paid by our rate payers as requested in our general rate case filings

        Approved in April 2009, the Low Carbon Fuel Standard Program, which went into effect January 1, 2011, requires diesel engines to use low carbon fuel such as biodiesel or other alternatives. This may increase the operating cost of our generators and vehicles.

        We maintain a fleet of vehicles to provide service to our customers, including a number of heavy duty diesel vehicles that we retrofitted by the end of 2010 to meet California emission standards. If future legislation further impacts the cost to operate the fleet or the fleet acquisition cost in order to meet certain emission standards, it will increase our cost of service and our rate base. Any increase in fleet operating costs associated with meeting emission standards will be included in our cost of service paid by our rate payers as requested in our general rate case filings. While recovery of these costs are not guaranteed, we would expect recovery in the regulatory process.

        Starting January 1, 2010, under the California Environmental Quality Act (CEQA), all capital projects of a certain type (primarily wells, tanks, major pipelines and treatment facilities) will require mitigation of green house gas emissions. The cost to prepare the CEQA documentation and permit will add an estimated ten thousand dollars to such capital projects. This cost will be included in our capital cost and added to our rate base, which will be requested to be paid for by our rate payers. Any increase in the operating cost of the facilities will also be included in our cost of service paid by our rate payers as requested in our general rate case filings. While recovery of these costs are not guaranteed, we would expect recovery in the regulatory process.

        Proposed cap and trade regulations are scheduled to be implemented in 2012 with the goal of reducing emissions to 1990 levels by the year 2020. Under such regulations, if approved, we will be required to determine our carbon footprint and evaluate our electricity and fuel usage (both diesel and gasoline). We will also be required to evaluate methane emissions from our primary processes in our wastewater plants. At this time we are unable to determine the cost impact of such regulations but any increase in operating costs associated with the cap and trade regulations will be included in our cost of service requested to be paid by our rate payers as requested in our general rate case filings. While recovery of these costs are not guaranteed, we would expect recovery in the regulatory process.

Security at Company Facilities

        Due to terrorist and other risks, we have heightened security at our facilities and have taken added precautions to protect our employees and the water delivered to customers. In 2002, federal legislation was enacted that resulted in new regulations concerning security of water facilities, including submitting vulnerability assessment studies to the federal government. We have complied with regulations issued by the Environmental Protection Agency (EPA) pursuant to our federal legislation concerning vulnerability assessments and have made filings to the EPA as required. In addition, communication

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plans have been developed as a component of our procedures. While we do not make public comments on our security programs, we have been in contact with federal, state, and local law enforcement agencies to coordinate and improve our water delivery systems' security.

Quality of Water Supply

        Our operating practices are designed to produce potable water in accordance with accepted water utility practices. Water entering the distribution systems from surface sources is treated in compliance with federal and state Safe Drinking Water Acts (SDWA) standards. Most well supplies are chlorinated or chloraminated for disinfection. Water samples from each water system are analyzed on a regular, scheduled basis in compliance with regulatory requirements. We operate a state-certified water quality laboratory at the San Jose General Office that provides testing for most of our California operations. Certain tests in California are contracted with independent certified labs qualified under the Environmental Laboratory Accreditation Program. Local independent state certified labs provide water sample testing for the Washington, New Mexico and Hawaii operations.

        In recent years, federal and state water quality regulations have continued to increase water testing requirements. The SDWA continues to be amended to reflect new public health concerns. We monitor water quality standard changes and upgrade our treatment capabilities to maintain compliance with the various regulations.

Competition and Condemnation

        Our principal operations are regulated by the Commission of each state. Under state laws, no privately owned public utility may compete within any service territory that we already serve without first obtaining a certificate of public convenience and necessity from the applicable Commission. Issuance of such a certificate would only be made upon finding that our service is deficient. To management's knowledge, no application to provide service to an area served by us has been made.

        State law provides that whenever a public agency constructs facilities to extend a utility system into the service area of a privately owned public utility, such an act constitutes the taking of property and requires reimbursement to the utility for its loss. State statutes allow municipalities, water districts and other public agencies to own and operate water systems. These agencies are empowered to condemn properties already operated by privately owned public utilities. The agencies are also authorized to issue bonds, including revenue bonds, for the purpose of acquiring or constructing water systems. However, if a public agency were to acquire utility property by eminent domain action, the utility would be entitled to just compensation for its loss. In Washington, annexation was approved in February 2008 for property served by us on Orcas Island; however, we continue to serve the customers in the annexed area and do not expect the annexation to impact our operations. To management's knowledge, other than the Orcas Island property, no municipality, water district, or other public agency is contemplating or has any action pending to acquire or condemn any of our systems.

        We intend to continue the pursuit of opportunities to expand our business in the western United States, which may include expansion through acquisitions or mergers with other companies.

Environmental Matters

        Our operations are subject to environmental regulation by various governmental authorities. Environmental affairs programs have been designed to provide compliance with water discharge regulations, underground and aboveground fuel storage tank regulations, hazardous materials management plans, hazardous waste regulations, air quality permitting requirements, wastewater discharge limitations and employee safety issues related to hazardous materials. Also, we actively investigate alternative technologies for meeting environmental regulations and continue the traditional practices of meeting environment regulations.

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        For a description of the material effects that compliance with environmental regulations may have on us, see Item 1A. "Risk Factors—Risks Related to Our Regulatory Environment." We expect environmental regulation to increase, resulting in higher operating costs in the future, which may have a material adverse effect on earnings.

Employees

        At year-end 2011, we had 1,132 employees, including 56 at Washington Water, 56 at Hawaii Water, and 16 at New Mexico Water. In California, most non-supervisory employees are represented by the Utility Workers Union of America, AFL-CIO, except certain engineering and laboratory employees who are represented by the International Federation of Professional and Technical Engineers, AFL-CIO.

        At December 31, 2011, there were 703 union employees. In December 2011, we negotiated 2012 wage increases with both of our unions of 3.25%. The wage increases for 2013 and 2014 will be negotiated at a later date. The current agreement with the unions is effective through 2014. Management believes that it maintains good relationships with the unions.

        Employees at Washington Water, New Mexico Water, and Hawaii Water are not represented by unions.

Executive Officers of the Registrant

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Item 1A.    Risk Factors.

        If any of the following risks actually occur, our financial condition and results of operations could be materially and adversely affected.

Risks Related to Our Regulatory Environment

Our business is heavily regulated by state and federal regulatory agencies and our financial viability depends upon our ability to recover costs from our customers through rates that must be approved by state public utility commissions.

        California Water Service Company, New Mexico Water Service Company, Washington Water Service Company and Hawaii Water Service Company, Inc., are regulated public utilities which provide water service to our customers. The rates that we charge our water customers are subject to the jurisdiction of the regulatory commissions in the states in which we operate. These commissions set water rates for each operating district independently because the systems are not interconnected. The commissions authorize us to charge rates which they consider to be sufficient to recover normal operating expenses, to provide funds for adding new or replacing water infrastructure, and to allow us to earn what the commissions consider to be a fair and reasonable return on invested capital.

        Our revenues and consequently our ability to meet our financial objectives are dependent upon the rates we are authorized to charge our customers by the commissions and our ability to recover our costs in these rates. Our management uses forecasts, models and estimates in order to set rates that will provide a fair and reasonable return on our invested capital. While our rates must be approved by the commissions, no assurance can be given that our forecasts, models and estimates will be correct or that the commissions will agree with our forecasts, models and estimates. If our rates are set too low, our revenues may be insufficient to cover our operating expenses, capital expenditure requirements and desired dividend levels.

        We periodically file rate increase applications with the commissions. The ensuing administrative and hearing process may be lengthy and costly. The decisions of the commissions are beyond our control and we can provide no assurances that our rate increase requests will be granted by the commissions. Even if approved, there is no guarantee that approval will be given in a timely manner or at a sufficient level to cover our expenses and provide a reasonable return on our investment. If the rate increase decisions are delayed, our earnings may be adversely affected.

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Our evaluation of the probability of recovery of regulatory assets is subject to adjustment by regulatory agencies and any such adjustment could adversely affect our results of operations.

        Regulatory decisions may also impact prospective revenues and earnings, affect the timing of the recognition of revenues and expenses and may overturn past decisions used in determining our revenues and expenses. Our management continually evaluates the anticipated recovery of regulatory assets, liabilities, and revenues subject to refund and provides for allowances and/or reserves as deemed necessary. Current accounting procedures allow us to defer certain costs if we believe it is probable that we will be allowed to recover those costs by future rate increases. If a commission determined that a portion of our assets were not recoverable in customer rates, we may suffer an asset impairment which would require a write down in such asset's valuation which would be recorded through operations.

        If our assessment as to the probability of recovery through the ratemaking process is incorrect, the associated regulatory asset or liability would be adjusted to reflect the change in our assessment or any regulatory disallowances. A change in our evaluation of the probability of recovery of regulatory assets or a regulatory disallowance of all or a portion of our cost could have a material adverse effect on our financial results.

Regulatory agencies may disagree with our valuation and characterization of certain of our assets.

        If we determine that assets are no longer used or useful for utility operations, we may remove them from our rate base and subsequently sell those assets. If the commission disagrees with our characterization, we could be subjected to penalties. Furthermore, there is a risk that the commission could determine that appreciation in property value should be awarded to the ratepayers rather than our stockholders.

Changes in laws, rules and policies of regulatory agencies can significantly affect our business.

        Regulatory agencies may change their rules and policies for various reasons, including changes in the local political environment. In some states, regulators are elected by popular vote or are appointed by elected officials, and the results of elections may change the long-established rules and policies of an agency dramatically. For example, in 2001 regulation regarding recovery of increases in electrical rates changed in California. For over 20 years prior to 2001, the California Public Utilities Commission allowed recovery of electric rate increases under its operating rules. However, in 2003, the commission reinstated its policy to allow utilities to adjust their rates for rate changes by the power companies. The original decision by the commission to change its policy, as well as its subsequent decision to reinstate that policy, affected our business.

        We rely on policies and regulations promulgated by the various state commissions in order to recover capital expenditures, maintain favorable treatment on gains from the sale of real property, offset certain production and operating costs, recover the cost of debt, maintain an optimal equity structure without over-leveraging, and have financial and operational flexibility to engage in non-regulated operations. If any of the commissions with jurisdiction over us implements policies and regulations that do not allow us to accomplish some or all of the items listed above, our future operating results may be adversely affected.

        In addition, legislatures may repeal, relax or tighten existing laws, or enact new laws that impact the regulatory agencies with jurisdiction over our business or affect our business directly. If changes in existing laws or the implementation of new laws limit our ability to accomplish some or all of our business objectives, our future operating results may be adversely affected.

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We expect environmental regulation to increase, resulting in higher operating costs in the future.

        Our water and wastewater services are governed by various federal and state environmental protection, health and safety laws, and regulations. These provisions establish criteria for drinking water and for discharges of water, wastewater and airborne substances. The Environmental Protection Agency promulgates numerous nationally applicable standards, including maximum contaminant levels (MCLs) for drinking water. We believe we are currently in compliance with all of the MCLs promulgated to date but we can give no assurance that we will continue to comply with all water quality requirements. If we violate any federal or state regulations or laws governing health and safety, we could be subject to substantial fines or otherwise sanctioned.

        Environmental laws are complex and change frequently. They tend to become more stringent over time. As new or stricter standards are introduced, they could increase our operating costs. Although we would likely seek permission to recover these costs through rate increases, we can give no assurance that the commissions would approve rate increases to enable us to recover these additional compliance costs.

        We are required to test our water quality for certain chemicals and potential contaminants on a regular basis. If the test results indicate that we exceed allowable limits, we may be required either to commence treatment to remove the contaminant or to develop an alternate water source. Either of these results may be costly, and there can be no assurance that the commissions would approve rate increases to enable us to recover these additional compliance costs.

Legislation regarding climate change may impact our operations

        Future legislation regarding climate change may restrict our operations or impose new costs on our business. Our operations depend on power provided by other public utilities and, in emergencies, power generated by our portable and fixed generators. If future legislation limits emissions from the power generation process, our cost of power may increase. Any increase in the cost of power will be passed along to our California rate payers through the MCBA or included in our cost of service paid by our rate payers as requested in our general rate case filings. While recovery of these costs is not guaranteed, we would expect recovery in the regulatory process.

        The Low Carbon Fuel Standard Program, which went into effect January 1, 2011, requires diesel engines to use low carbon fuel such as biodiesel or other alternatives. This may increase the operating cost of our generators and vehicles.

        We maintain a fleet of vehicles to provide service to our customers, including a number of heavy duty diesel vehicles that we retrofitted by the end of 2010 to meet California emission standards. If future legislation further impacts the cost to operate the fleet or the fleet acquisition cost in order to meet certain emission standards, it will increase our cost of service and our rate base. Any increase in fleet operating costs associated with meeting emission standards will be included in our cost of service paid by our rate payers as requested in our general rate case filings. While recovery of these costs is not guaranteed, we would expect recovery in the regulatory process.

        Starting January 1, 2010, under the California Environmental Quality Act (CEQA), all capital projects of a certain type (primarily wells, tanks, major pipelines and treatment facilities) will require mitigation of green house gas emissions. The cost to prepare the CEQA documentation and permit will add an estimated ten thousand dollars to such capital projects. This cost will be included in our capital cost and added to our rate base, which will be requested to be paid for by our rate payers. Any increase in the operating cost of the facilities will also be included in our cost of service paid by our rate payers as requested in our general rate case filings. While recovery of these costs is not guaranteed, we would expect recovery in the regulatory process.

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        Proposed cap and trade regulations are scheduled to be implemented in 2012 with the goal of reducing emissions to 1990 levels by the year 2020. Under such regulations, if approved, we will be required to determine our carbon footprint and evaluate our electricity and fuel usage (both diesel and gasoline). We will also be required to evaluate methane emissions from our primary processes in our wastewater plants. At this time we are unable to determine the cost impact of such regulations but any increase in operating costs associated with the cap and trade regulations will be included in our cost of service requested to be paid by our rate payers as requested in our general rate case filings. While recovery of these costs is not guaranteed, we would expect recovery in the regulatory process.

We are party to a toxic contamination lawsuit which could result in our paying damages not covered by insurance.

        We have been and may be in the future, party to water contamination lawsuits, which may not be fully covered by insurance.

        The number of environmental and product-related lawsuits against other water utilities have increased in frequency in recent years. If we are subject to additional environmental or product-related lawsuits, we might incur significant legal costs and it is uncertain whether we would be able to recover the legal costs from ratepayers or other third parties. In addition, if current California law regarding California Public Utilities Commission's preemptive jurisdiction over regulated public utilities for claims about compliance with California Department of Health Services and United States Environmental Protection Agency water quality standards changes, our legal exposure may be significantly increased.

Risks Related to Our Business Operations

Wastewater operations entail significant risks.

        While wastewater collection and treatment is not presently a major component of our revenues, wastewater collection and treatment involve many risks associated with damage to the surrounding environment. If collection or treatment systems fail or do not operate properly, untreated or partially treated wastewater could discharge onto property or into nearby streams and rivers, causing property damage or injury to aquatic life, or even human life. Liabilities resulting from such damage could materially and adversely affect our results of operations and financial condition.

Demand for our water is subject to various factors and is affected by seasonal fluctuations.

        Demand for our water during the warmer, dry months is generally greater than during cooler or rainy months due primarily to additional requirements for water in connection with irrigation systems, swimming pools, cooling systems and other outside water use. Throughout the year, and particularly during typically warmer months, demand will vary with temperature and rainfall levels. If temperatures during the typically warmer months are cooler than normal, or if there is more rainfall than normal, the demand for our water may decrease. Under the WRAM mechanism, lower water usage impacts our cash flows in the year of usage, but results in higher cash flows in the following years.

        In addition, governmental restrictions on water usage during drought conditions may result in a decreased demand for our water, even if our water reserves are sufficient to serve our customers during these drought conditions. However, during the drought of the late 1980's and early 1990's the California Public Utilities Commission beginning in 1992 allowed us to surcharge our customers to collect lost revenues caused by customers' conservation during the drought. Regardless of whether we may surcharge our customers during a conservation period, they may use less water even after a drought has passed because of conservation patterns developed during the drought. Furthermore, our customers may wish to use recycled water as a substitute for potable water. If rights are granted to others to serve our customers recycled water, there will likely be a decrease in demand for our water.

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The adequacy of our water supplies depends upon a variety of factors beyond our control. Interruption in the water supply may adversely affect our earnings.

        We depend on an adequate water supply to meet the present and future needs of our customers. Whether we have an adequate supply varies depending upon a variety of factors, many of which are partially or completely beyond our control, including:

•

the amount of rainfall;



•

the amount of water stored in reservoirs;



•

underground water supply from which well water is pumped;



•

availability from water wholesalers;



•

changes in the amount of water used by our customers;



•

water quality;



•

legal limitations on water use such as rationing restrictions during a drought; and



•

population growth.

        We purchase our water supply from various governmental agencies and others. Water supply availability may be affected by weather conditions, funding and other political and environmental considerations. In addition, our ability to use surface water is subject to regulations regarding water quality and volume limitations. If new regulations are imposed or existing regulations are changed or given new interpretations, the availability of surface water may be materially reduced. A reduction in surface water could result in the need to procure more costly water from other sources, thereby increasing our water production costs and adversely affecting our operating results.

        We have entered into long-term water supply agreements, which commit us to making certain minimum payments whether or not we purchase any water. Therefore, if demand is insufficient to use our required purchases we would have to pay for water we did not receive.

        From time to time, we enter into water supply agreements with third parties and our business is dependent upon such agreements in order to meet regional demand. For example, we have entered into a water supply contract with the San Francisco Public Utilities Commission that expires on June 30, 2034. We can give no assurance that the San Francisco Public Utilities Commission, or any of the other parties from whom we purchase water, will renew our contracts upon expiration, or that we will not be subject to significant price increases under any such renewed contracts.

        The parties from whom we purchase water maintain significant infrastructure and systems to deliver water to us. Maintenance of these facilities is beyond our control. If these facilities are not adequately maintained or if these parties otherwise default on their obligations to supply water to us, we may not have adequate water supplies to meet our customers' needs.

        If we are unable to access adequate water supplies we may be unable to satisfy all customer demand which could result in rationing. Rationing may have an adverse effect on cash flow from operations. We can make no guarantee that we will always have access to an adequate supply of water that will meet all required quality standards. Water shortages may affect us in a variety of ways. For example, shortages could:

•

adversely affect our supply mix by causing us to rely on more expensive purchased water;



•

adversely affect operating costs;



•

increase the risk of contamination to our systems due to our inability to maintain sufficient pressure; and

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•

increase capital expenditures for building pipelines to connect to alternative sources of supply, new wells to replace those that are no longer in service or are otherwise inadequate to meet the needs of our customers and reservoirs and other facilities to conserve or reclaim water.

        We may or may not be able to recover increased operating and construction costs on a timely basis, or at all, for our regulated systems through the ratemaking process. Although we can give no assurance, we may also be able to recover certain of these costs from third parties that may be responsible, or potentially responsible, for groundwater contamination.

Changes in water supply costs impact our operations.

        The cost to obtain water for delivery to our customers varies depending on the sources of supply, wholesale suppliers' prices, the quality of water required to be treated and the quantity of water produced to fulfill customer water demand. Our source of supply varies among our operating districts. Certain districts obtain all of their supply from wells; some districts purchase all of the supply from wholesale suppliers; and other districts obtain the supply from a combination of wells and wholesale suppliers. A small portion of supply comes from surface sources and is processed through Company-owned water treatment plants. On average, slightly more than half of the water we deliver to our customers is pumped from wells or received from a surface supply with the remainder purchased from wholesale suppliers. Water purchased from suppliers usually costs us more than surface supplied or well pumped water. The cost of purchased water for delivery to customers represented 32.8% and 31.6% of our total operating costs in 2011 and 2010, respectively.

        Wholesale water suppliers may increase their prices for water delivered to us based on factors that affect their operating costs. Purchased water rate increases are beyond our control. In California, effective July 1, 2008, our ability to recover increases in the cost of purchased water changed with the adoption of the MCBA. With this change, actual purchased water costs are compared to authorized purchased water costs with variances, netted against variance in purchased power, pump tax, and metered revenue, recorded to revenue. The balance in the MCBA will be collected in the future by billing the net WRAM and MCBA accounts receivable balances over 12, 24, and 36 month periods, which may have a short-term negative impact on cash flow.

Dependency upon adequate supply of electricity and certain chemicals could adversely affect our results of operations.

        Purchased electrical power is required to operate the wells and pumps needed to supply water to our customers. Although there are back-up power generators to operate a number of wells and pumps in emergencies, an extended interruption in power could impact the ability to supply water. In the past, California has been subject to rolling power blackouts due to insufficient power supplies. There is no assurance we will not be subject to power blackouts in the future. Additionally, we require sufficient amounts of certain chemicals in order to treat the water we supply. There are multiple sources for these chemicals but an extended interruption of supply could adversely affect our ability to adequately treat our water.

        Purchased power is a significant operating expense. During 2011 and 2010, purchased power expense represented 6.9% and 7.4% of our total operating costs, respectively. These costs are beyond our control and can change unpredictably and substantially as occurred in California during 2001 when rates paid for electricity increased 48%. As with purchased water, purchased power costs are included in the MCBA. Cash flows between rate filings may be adversely affected until the commission authorizes a rate change but earnings will be minimally impacted. Cost of chemicals used in the delivery of water is not an element of the MCBA and therefore variances in quantity or cost could impact the results of operations.

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Our ability to generate new operating contracts or renewal of existing operating contracts is affected by local politics.

        Our revenue and non-regulated revenue growth depends upon our ability to generate new as well as renew operating contracts with cities, other agencies and municipal utility districts. As our services are sold in a political environment, there is exposure to changing trends and municipal preferences. Terrorist acts have affected some political viewpoints relative to outsourcing of water or wastewater utility services. Municipalities own and municipal employees operate the majority of water and wastewater systems. Significant marketing and sales efforts are spent demonstrating the benefits of contract operations to elected officials and municipal authorities. The existing political environment means decisions affecting our business are based on many factors, not just economic factors.

Our business requires significant capital expenditures that are dependent on our ability to secure appropriate funding. If we are unable to obtain sufficient capital or if the rates at which we borrow increase, there would be a negative impact on our results of operations.

        The water utility business is capital-intensive. We invest significant funds to add or replace property, plant and equipment. In addition, water shortages may adversely affect us by causing us to rely on more purchased water. This could cause increases in capital expenditures needed to build pipelines to secure alternative water sources. In addition, we require capital to grow our business through acquisitions. We fund our short-term capital requirements from cash received from operations and funds received from developers. We also borrow funds from banks under short-term bank lending arrangements. We seek to meet our long-term capital needs by raising equity through common or preferred stock issues or issuing debt obligations. We cannot give any assurance that these sources will continue to be adequate or that the cost of funds will remain at levels permitting us to earn a reasonable rate of return. In the event we are unable to obtain sufficient capital, our expansion efforts could be curtailed, which may affect our growth and may affect our future results of operations.

        Our ability to access the capital markets is affected by the ratings of certain of our debt securities. Standard & Poor's Rating Agency issues a rating on California Water Service Company's ability to repay certain debt obligations. The credit rating agency could downgrade our credit rating based on reviews of our financial performance and projections or upon the occurrence of other events that could impact our business outlook. Lower ratings by the agency could restrict our ability to access equity and debt capital. We can give no assurance that the rating agency will maintain ratings which allow us to borrow under advantageous conditions and at reasonable interest rates. A future downgrade by the agency could also increase our cost of capital by causing potential investors to require a higher interest rate due to a perceived risk related to our ability to repay outstanding debt obligations.

        While the majority of our debt is long term at fixed rates, we do have interest rate exposure in our short-term borrowings which have variable interest rates. We are also subject to interest rate risks on new financings. However, if interest rates were to increase on a long-term basis, our management believes that customer rates would increase accordingly, subject to approval by the appropriate commission. We can give no assurance that the commission would approve such an increase in customer rates.

        We are obligated to comply with specified debt covenants under certain of our loan and debt agreements. Failure to maintain compliance with these covenants could limit future borrowing, and we could face increased borrowing costs, litigation, acceleration of maturity schedules, and cross default issues. Such actions by our creditors could have a material adverse effect on our financial condition and results of operations.

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Adverse changes to the national and world-wide financial system could result in disruptions in the financial and real estate markets availability and cost of short-term funds for our liquidity requirements, our ability to meet long-term commitments, and our customers' ability to pay for water services. Any of these could adversely affect our results of operations, cash flows and financial condition.

        We rely on our current credit facilities to fund short-term liquidity needs if internal funds are not available from operations. Specifically, given the seasonal fluctuations in demand for our water we commonly draw on our credit facilities to meet our cash requirements at times in the year when demand is relatively low. We also may occasionally use letters of credit issued under our revolving credit facilities. Disruptions in the capital and credit markets or further deterioration in the strength of financial institutions could adversely affect our ability to draw on our credit facilities. Our access to funds under our credit facilities is dependent on the ability of our banks to meet its funding commitments.

        Longer-term disruptions in the financial markets as a result of uncertainty, changing or increased regulation, reduced capital-raising alternatives, or failures of significant financial institutions or other factors could adversely affect our access to liquidity. Any disruption could require us to take measures to conserve cash until the markets stabilize or until alternative credit arrangements or other funding for business needs can be arranged. Such measures could include deferring capital expenditures, dividend payments or other discretionary uses of cash.

        Many of our customers and suppliers also have exposure to risks that could affect their ability to meet payment and supply commitments. We operate in geographic areas that may be particularly susceptible to declines in the price of real property, which could result in significant declines in demand for our products and services. In the event that any of our significant customers or suppliers, or a significant number of smaller customers and suppliers, are adversely affected by these risks, we may face disruptions in supply, significant reductions in demand for our products and services, inability of customers to pay invoices when due, and other adverse effects that could negatively affect our financial condition, results of operations and/or cash flows.

        Our operations and certain contracts for water distribution and treatment depend on the financial capability of state and local governments, and other municipal entities such as water districts. Major disruptions in the financial strength or operations of such entities, such as liquidity limitations, bankruptcy or insolvency, could have an adverse effect on our ability to conduct our business and/or enforce our rights under contracts to which such entities are a party.

We are a holding company that depends on cash flow from our subsidiaries to meet our obligations and to pay dividends on our common stock.

        As a holding company, we conduct substantially all of our operations through our subsidiaries and our only significant assets are investments in those subsidiaries. 94% of our revenues are derived from the operations of California Water Service Company. As a result, we are dependent on cash flow from our subsidiaries, and California Water Service Company in particular, to meet our obligations and to pay dividends on our common stock.

        We can make dividend payments only from our surplus (the excess, if any, of our net assets over total paid-in capital) or if there is no surplus, the net profits for the current fiscal year or the fiscal year before which the dividend is declared. In addition, we can pay cash dividends only if after paying those dividends we would be able to pay our liabilities as they become due. Owners of our capital stock cannot force us to pay dividends and dividends will only be paid if and when declared by our board of directors. Our board of directors can elect at any time, and for an indefinite duration, not to declare dividends on our capital stock.

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        Our subsidiaries are separate and distinct legal entities and generally have no obligation to pay any amounts due on California Water Service Group's debt or to provide California Water Service Group with funds for dividends. Although there are no contractual or regulatory restrictions on the ability of our subsidiaries to transfer funds to us, the reasonableness of our capital structure is one of the factors considered by state and local regulatory agencies in their ratemaking determinations. Therefore, transfer of funds from our subsidiaries to us for the payment of our obligations or dividends may have an adverse effect on ratemaking determinations. Furthermore, our right to receive cash or other assets upon the liquidation or reorganization of a subsidiary is generally subject to the prior claims of creditors of that subsidiary. If we are unable to obtain funds from our subsidiaries in a timely manner, we may be unable to meet our obligations or pay dividends.

An important element of our growth strategy is the acquisition of water and wastewater systems. Risks associated with potential acquisitions, divestitures or restructurings may adversely affect us.

        We may seek to acquire or invest in other companies, technologies, services or products that complement our business. The execution of our growth strategy may expose us to different risks than those associated with our utility operations. We can give no assurance that we will succeed in finding attractive acquisition candidates or investments, or that we would be able to reach mutually agreeable terms with such parties. In addition, as consolidation becomes more prevalent in the water and wastewater industries, the prices for suitable acquisition candidates may increase to unacceptable levels and limit our ability to grow through acquisitions. If we are unable to find acquisition candidates or investments, our ability to grow may be limited.

        Acquisition and investment transactions may result in the issuance of our equity securities that could be dilutive if the acquisition or business opportunity does not develop in accordance with our business plan. They may also result in significant write-offs and an increase in our debt. The occurrence of any of these events could have a material adverse effect on our business, financial condition and results of operations.

        Any of these transactions could involve numerous additional risks, including one or more of the following:

•

problems integrating the acquired operations, personnel, technologies or products with our existing businesses and products;



•

liabilities inherited from the acquired companies' prior business operations;



•

diversion of management time and attention from our core business to the acquired business;



•

failure to retain key technical, management, sales and other personnel of the acquired business;



•

difficulty in retaining relationships with suppliers and customers of the acquired business; and



•

difficulty in getting required regulatory approvals.

        In addition, the businesses and other assets we acquire may not achieve the sales and profitability expected. The occurrence of one or more of these events may have a material adverse effect on our business. There can be no assurance that we will be successful in overcoming these or any other significant risks encountered.

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We may not be able to increase or sustain our recent growth rate, and we may not be able to manage our future growth effectively.

        We may be unable to continue to expand our business or manage future growth. To successfully manage our growth and handle the responsibilities of being a public company, we believe we must effectively:

•

hire, train, integrate and manage additional qualified engineers for engineering design and construction activities, new business personnel, and financial and information technology personnel;



•

retain key management, augment our management team, and retain qualified and certified water and wastewater system operators;



•

implement and improve additional and existing administrative, financial and operations systems, procedures and controls;



•

expand and upgrade our technological capabilities; and



•

manage multiple relationships with our customers, regulators, suppliers and other third parties.

        If we are unable to manage our growth effectively, we may not be able to take advantage of market opportunities, satisfy customer requirements, execute our business plan or respond to competitive pressures.

We have a number of large-volume commercial and industrial customers and a significant decrease in consumption by one or more of these customers could have an adverse effect on our operating results and cash flows.

        Our billed revenues will decrease, and such decrease may be material, if a significant business or industrial customer terminates or materially reduces its use of our water. Approximately $124.7 million, or 24.8%, of our 2011 water utility revenues was derived from business and industrial customers. If any of our large business or industrial customers in California reduce or cease its consumption of our water, the impact to net operating income would be minimal to our operations due to the WRAM and MCBA, but could impact our cash flows. In Hawaii, we serve a number of large resorts which if their water usage was reduced or ceased could have a material impact to our Hawaii operation. The delay between such date and the effective date of the rate relief may be significant and could adversely affect our operating results and cash flows.

Our operating cost and costs of providing services may rise faster than our revenues.

        Our ability to increase rates over time is dependent upon approval of such rate increases by state commissions, or in the case of the City of Hawthorne and the City of Commerce, the City Council, which may be inclined, for political or other reasons, to limit rate increases. However, our costs are subject to market conditions and other factors, which may increase significantly. The second largest component of our operating costs after water production is made up of salaries and wages. These costs are affected by the local supply and demand for qualified labor. Other large components of our costs are general insurance, workers compensation insurance, employee benefits and health insurance costs. These costs may increase disproportionately to rate increases authorized by state commissions and may have a material adverse effect on our future results of operations.

Our non-regulated business operates in a competitive market.

        While a majority of our business is regulated, our non-regulated business participates in a competitive market. We compete with several larger companies whose size, financial resources, customer base and technical expertise may restrict our ability to compete successfully for certain operations and maintenance contracts. Due to the nature of our contract operations business, and to the very competitive nature of the market, we must accurately estimate the cost and profitability of

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each project while, at the same time, maintaining prices at a level low enough to compete with other companies. Our inability to achieve this balance could adversely impact our results of operations.

Demand for our stock may fluctuate due to circumstances beyond our control.

        We believe that stockholders invest in public utility stocks, in part, because they seek reliable dividend payments. If there is an over-supply of stock of public utilities in the market relative to demand by such investors, the trading price of our securities could decrease. Additionally, if interest rates rise above the dividend yield offered by our equity securities, demand for our stock, and consequently its market price, may also decrease. A decline in demand for our stock may have a negative impact on our ability to finance capital projects.

The price of our common stock may be volatile and may be affected by market conditions beyond our control.

        The trading price of our common stock may fluctuate in the future because of the volatility of the stock market and a variety of other factors, many of which are beyond our control. Factors that could cause fluctuations in the trading price of our common stock include: regulatory developments; general economic conditions and trends; price and volume fluctuations in the overall stock market from time to time; actual or anticipated changes or fluctuations in our results of operations; actual or anticipated changes in the expectations of investors or securities analysts; actual or anticipated developments in our competitors' businesses or the competitive landscape generally; litigation involving us or our industry; and major catastrophic events or sales of large blocks of our stock.

        Equity markets in general can experience extreme price and volume fluctuations. Such price and volume fluctuations may continue to adversely affect the market price of our common stock for reasons unrelated to our business or operating results.

Adverse investment returns and other factors may increase our pension liability and pension funding requirements.

        A substantial number of our employees are covered by a defined benefit pension plan. At present, the pension plan is underfunded because our projected pension benefit obligation exceeds the aggregate fair value of plan assets. Under applicable law, we are required to make cash contributions to the extent necessary to comply with minimum funding levels imposed by regulatory requirements. The amount of such required cash contribution is based on an actuarial valuation of the plan. The funded status of the plan can be affected by investment returns on plan assets, discount rates, mortality rates of plan participants, pension reform legislation and a number of other factors. There can be no assurance that the value of our pension plan assets will be sufficient to cover future liabilities. Although we have made contributions to our pension plan in recent years, it is possible that we could incur a pension liability adjustment, or could be required to make additional cash contributions to our pension plan, which would reduce the cash available for business and other needs.

Work stoppages and other labor relations matters could adversely affect our operating results.

        At December 31, 2011, 703 of our 1,132 total employees were union employees. Most of our unionized employees are represented by the Utility Workers Union of America, AFL-CIO, except certain engineering and laboratory employees who are represented by the International Federation of Professional and Technical Engineers, AFL-CIO.

        We believe our labor relations are good, but in light of rising costs for healthcare and pensions, contract negotiations in the future may be difficult. Furthermore, changes in applicable law or regulations could have an adverse effect on management's negotiating position with respect to our currently unionized employees and/or employees that decide to unionize in the future. We are subject to a risk of work stoppages and other labor relations matters as we negotiate with the unions to address these issues, which could affect our results of operations and financial condition. We can give

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no assurance that issues with our labor forces will be resolved favorably to us in the future or that we will not experience work stoppages.

We depend significantly on the services of the members of our management team, and the departure of any of those persons could cause our operating results to suffer.

        Our success depends significantly on the continued individual and collective contributions of our management team. The loss of the services of any member of our management team could have a material adverse effect on our business as our management team has knowledge of our industry and customers and would be difficult to replace.

Our operations are geographically concentrated in California and this lack of diversification may negatively impact our operations.

        Although we own facilities in a number of states, over 94% of our operations are located in California. As a result, we are largely subject to weather, political, water supply, labor, utility cost, regulatory and economic risks affecting California.

        We are also affected by the real property market in California. In order to grow our business, we may need to acquire additional real estate or rights to use real property owned by third parties, the cost of which tends to be higher and more volatile in California relative to other states. The value of our assets in California may decline if there is a decline in the California real estate market which results in a significant decrease in real property values.

        In 2008 and 2009, we experienced higher than normal uncollectible accounts activity which, we believe, were attributable in part to the significant declines in real estate values and rising unemployment experienced by our customers in a number of our districts in California due to the economic recession. We may experience higher than normal uncollectible accounts activity if real estate values decline and unemployment rates continue to increase.

The effects of natural disasters, terrorist activity, pandemics, or poor water quality or contamination to our water supply may result in disruption in our services and litigation which could adversely affect our business, operating results and financial condition.

        We operate in areas that are prone to earthquakes, fires, mudslides and other natural disasters. A significant seismic event or other natural disaster in California where our operations are concentrated could adversely impact our ability to deliver water and adversely affect our costs of operations. A major disaster could damage or destroy substantial capital assets. The California Public Utilities Commission has historically allowed utilities to establish a catastrophic event memorandum account as another possible mechanism to recover costs. However, we can give no assurance that the CPUC or any other commission would allow any such cost recovery mechanism in the future.

        Our water supplies are subject to contamination, including contamination from the development of naturally-occurring compounds, chemicals in groundwater systems, pollution resulting from man-made sources, such as MTBE, sea water incursion and possible terrorist attacks. If our water supply is contaminated, we may have to interrupt the use of that water supply until we are able to substitute the flow of water from an uncontaminated water source. In addition, we may incur significant costs in order to treat the contaminated source through expansion of our current treatment facilities, or development of new treatment methods. If we are unable to substitute water supply from an uncontaminated water source, or to adequately treat the contaminated water source in a cost-effective manner, there may be an adverse effect on our revenues, operating results and financial condition. The costs we incur to decontaminate a water source or an underground water system could be significant and could adversely affect our business, operating results and financial condition and may not be recoverable in rates. We could also be held liable for consequences arising out of human exposure to hazardous substances in our water supplies or other environmental damage. For example, private

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plaintiffs have the right to bring personal injury or other toxic tort claims arising from the presence of hazardous substances in our drinking water supplies. Our insurance policies may not be sufficient to cover the costs of these claims.

        We operate a dam. If the dam were to fail for any reason, we would lose a water supply and flooding likely would occur. Whether or not we were responsible for the dam's failure, we could be sued. We can give no assurance that we would be able to successfully defend such a suit.

        In light of the threats to the nation's health and security ensuing in the wake of the September 11, 2001 terrorist attacks, we have taken steps to increase security measures at our facilities and heighten employee awareness of threats to our water supply. We have also tightened our security measures regarding the delivery and handling of certain chemicals used in our business. We have and will continue to bear increased costs for security precautions to protect our facilities, operations and supplies. These costs may be significant. Despite these tightened security measures, we may not be in a position to control the outcome of terrorist events should they occur.

        We depend upon our skilled and trained workforce to ensure water delivery. Were a pandemic to occur, we can give no assurance that we would be able to maintain sufficient manpower to ensure uninterrupted service in all of the districts that we serve.

We retain certain risks not covered by our insurance policies.

        We evaluate our risks and insurance coverage annually. Our evaluation considers the costs, risks and benefits of retaining versus insuring various risks as well as the availability of certain types of insurance coverage. Furthermore, we are also affected by increases in prices for insurance coverage; in particular, we have been, and will continue to be, affected by rising health insurance costs. Retained risks are associated with deductible limits, partial self-insurance programs and insurance policy coverage ceilings. If we suffer an uninsured loss, we may be unable to pass all, or any portion, of the loss on to customers because our rates are regulated by regulatory commissions. Consequently, uninsured losses may negatively affect our financial condition, liquidity and results of operations. There can be no assurance that we will not face uninsured losses pertaining to the risks we have retained.

We rely on our information technology and a number of complex business systems that could malfunction and result in negative impacts on our profitability and cash flow.

        Our business is dependent on several complex business systems, certain of which are owned by third parties. The business systems must function reliably in order for us to operate effectively. Among other things, system malfunctions and security breaches could prevent us from operating or monitoring our facilities, billing accurately and timely analysis of financial results. Our profitability and cash flow could be affected negatively in the event these systems do not operate effectively or are circumvented.

The accuracy of our judgments and estimates about financial and accounting matters will impact our operating results and financial condition.

        We make certain estimates and judgments in preparing our financial statements regarding, among others:

•

the useful life of intangible rights;



•

the number of years to depreciate certain assets;



•

amounts to set aside for uncollectible accounts receivable, inventory obsolesces and uninsured losses;



•

our legal exposure and the appropriate accrual for claims, including medical claims and workers' compensation claims;



•

future costs and assumptions for pensions and other post-retirement benefits;

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•

regulatory recovery of deferred items; and



•

possible tax uncertainties;



•

projected collections of WRAM/MCBA receivables.

        The quality and accuracy of those estimates and judgments will have an impact on our operating results and financial condition.

        In addition, we must estimate unbilled revenues and costs as of the end of each accounting period. If our estimates are not accurate, we will be required to make an adjustment in a future period. Accounting rules permit us to use expense balancing accounts and memorandum accounts that include input cost changes to us that are different from amounts incorporated into the rates approved by the commissions. These accounts result in expenses and revenues being recognized in periods other than in which they occurred.

Our controls and procedures may fail or be circumvented.

        Management regularly reviews and updates our internal control over financial reporting, disclosure controls and procedures, and corporate governance policies and procedures. Any system of controls and procedures, however well designed and operated, is based in part on certain assumptions and can provide only reasonable, not absolute, assurances that the objectives of the system are met. Any failure or circumvention of our controls and procedures or failure to comply with regulations related to controls and procedures could result in lack of compliance with contractual agreements, misstatements in our financial statements in amounts that could be material or could cause investors to lose confidence in our reported financial information, either of which could have a negative effect on the trading price of our stock and may negatively affect our ability to raise future capital.

        Further, if we or our independent registered public accounting firm discover a material weakness in our internal control over financial reporting, the disclosure of that fact, even if quickly remedied, could reduce the market's confidence in our financial statements and harm our stock price. In addition, non-compliance with Section 404 of the Sarbanes-Oxley Act of 2002 could subject us to a variety of administrative sanctions, including the suspension or delisting of our common stock from the New York Stock Exchange and the inability of registered broker-dealers to make a market in our common stock, which would further reduce our stock price.

We may be required to adopt International Financial Reporting Standards (IFRS), or other accounting or financial reporting standards, the ultimate adoption of which could negatively impact our business, financial condition or results of operations.

        We could be required to adopt IFRS or other accounting or financial reporting standards different from Generally Accepted Accounting Principles (GAAP) in the United States of America, which is currently applicable to our accounting and financial reporting. In 2008 the SEC released a proposed roadmap for the adoption of IFRS according to which we could be required to adopt IFRS in the future. Under GAAP we are subject to the accounting procedures for accounting for the effects of certain types of regulation, which, among other things, allows us to defer certain costs if we believe it is probable that we will be allowed to recover those costs by future rate increases. Currently, IFRS does not contain provisions equivalent to the current GAAP accounting procedures. The implementation and adoption of new accounting or financial reporting standards could affect our reported performance, which in turn could favorably or unfavorably impact our business, financial condition or results of operations. Furthermore, the transition to and application of new accounting or financial reporting standards could result in increased administrative costs. The SEC is expected to make a final determination regarding the adoption of IFRS at a later date.

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Municipalities, water districts and other public agencies may condemn our property by eminent domain action.

        State statutes allow municipalities, water districts and other public agencies to own and operate water systems. These agencies are empowered to condemn properties already operated by privately owned public utilities. However, whenever a public agency constructs facilities to extend a utility system into the service area of a privately owned public utility, such an act constitutes the taking of property and requires reimbursement to the utility for its loss. If a public agency were to acquire our utility property by eminent domain action, we would be entitled to just compensation for our loss, but we would no longer have access to the condemned property nor would we be entitled to any portion of revenue generated from the use of such asset going forward.

Item 1B.    Unresolved Staff Comments.

        None

Item 2.    Properties.

        Our physical properties consist of offices and water facilities to accomplish the production, storage, treatment, and distribution of water. These properties are located in or near the geographic service areas listed above in Item 1, "Business—Geographical Service Areas and Number of Customers at Year-end." Our headquarters, which houses accounting, engineering, information systems, human resources, purchasing, regulatory, water quality, and executive staff, is located in San Jose, California.

        The real properties owned are held in fee simple title. Properties owned by Cal Water are subject to the lien of an Indenture of Mortgage and Deed of Trust dated April 17, 2009 (the California Indenture), securing Cal Water's first mortgage bonds, of which $464.7 million was outstanding at December 31, 2011. The California Indenture contains certain restrictions common to such types of instruments regarding the disposition of property and includes various covenants and restrictions. At December 31, 2011, our California utility was in compliance with the covenants of the California Indenture.

        Cal Water owns 630 wells and operates 5 leased wells. There are 429 owned storage tanks with a capacity of 489 million gallons, 3 leased storage tanks with a capacity of 0.7 million gallons, 37 managed storage tanks with a capacity of 30 million gallons, and 3 reservoirs with a capacity of 250 million gallons. Cal Water owns and operates 6 surface water treatment plants with a combined capacity of 46 million gallons per day. There are 5,730 miles of supply and distribution mains in the various systems.

        Hawaii Water owns 19 wells and manages 5 irrigation wells. There are 24 storage tanks with a storage capacity of 20 million gallons. There are 70 miles of supply and distribution lines. Hawaii Water operates 5 wastewater treatment facilities with a combined capacity to process approximately 1.7 million gallons per day. There are 26 miles of sewer collection mains.

        Washington Water owns 341 wells and manages 111 wells. There are 127 owned storage tanks and 45 managed storage tanks with a storage capacity of 9 million gallons. There are 328 miles of supply and distribution lines.

        New Mexico Water owns 17 wells. There are 12 storage tanks with a storage capacity of 4 million gallons. There are 134 miles of supply and distribution lines. New Mexico operates 2 waste water treatment facilities with a combined capacity to process 0.5 million gallons per day. There are 34 miles of sewer collection mains.

        Washington Water has long-term bank loans that are secured primarily by utility plant owned by Washington Water. New Mexico Water has a long-term loan that is secured by utility plant owned by New Mexico Water.

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        In the leased City of Hawthorne and City of Commerce systems or in systems that are operated under contract for municipalities or private companies, title to the various properties is held exclusively by the municipality or private company.

Item 3.    Legal Proceedings.

        Information with respect to this item may be found under the subheading "Contingencies" in Note 14 to the consolidated Financial Statements in Item 8, which is incorporated herein by reference.

Item 4.    Mine Safety Disclosures.

        Not applicable.

PART II

Item 5.    Market for Registrant's Equity, Related Stockholder Matters and Issuer Purchases of Equity Securities

        Our common stock is traded on the New York Stock Exchange under the symbol "CWT." At December 31, 2011, there were 41,817,032 common shares outstanding. There were 1,461 common stockholders of record as of February 6, 2012.

        During 2011, we paid a cash dividend of $0.615 per common share, or $0.15375 per quarter. During 2010, we paid a cash dividend of $0.595 per common share, or $0.14875 per quarter. In January 2012, our Board of Directors declared a quarterly cash dividend of $0.1575 per common share payable on February 17, 2012, to stockholders of record on February 6, 2012. This represents our 67th consecutive year of increasing the annual dividend and marks the 268th consecutive quarterly dividend.

        We presently intend to pay quarterly cash dividends in the future consistent with past practices, subject to our earnings and financial condition, restrictions set forth in our debt instruments, regulatory requirements and such other factors as our Board of Directors may deem relevant.

        During 2011 and 2010, the common stock market price range and dividends per share for each quarter were as follows:

        Amounts above have been restated to reflect the 2 for 1 stock split effective June 10, 2011, which was retroactively applied to our financial statements.

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Five-Year Performance Graph

        The following performance graph compares the changes in the cumulative shareholder return on California Water Service Group's common stock with the cumulative total return on the Robert W. Baird Water Utility Index and the Standard & Poor's 500 Index during the last five years ended December 31, 2011. The comparison assumes $100 was invested on December 31, 2006, in California Water Service Group's common stock and in each of the forgoing indices and assumes reinvestment of dividends.

Performance Graph Data

        The following descriptive data is supplied in accordance with Rule 304(d) of Regulations S-T:

        An initial $10,000 investment in the common stock of California Water Service Group on December 31, 2006 would have resulted in a cumulative total return of $11,298 over the 5-year period.

Item 6.    Selected Financial Data.

        The following selected consolidated financial data should be read in conjunction with our Consolidated Financial Statements and the Notes thereto and the information contained in Item 7, "Management's Discussion and Analysis of Financial Condition and Results of Operations."

        Historical results are not necessarily indicative of future results.

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FIVE YEAR FINANCIAL REVIEW

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Item 7.    Management's Discussion and Analysis of Financial Condition and Results of Operations.

Overview

        In 2011 and 2010, net income was $37.7 million. In 2011, the rate increases from the 2009 General Rate Case (GRC) and corresponding approved rates which were effective January 1, 2011, were offset by increases in water production costs, employee wage and benefit costs, depreciation expense increases from the 2009 GRC, a $1.5 million reduction to net income for the deferral of WRAM and MCBA revenues and associated operating expenses, interest expense to finance capital projects and operations, and a decrease in net other income. Net operating income increased $5.4 million to $67.2 million, or an 8.7% increase over 2010 levels. In 2011, net other income reflected a net decrease from the prior year of $2.0 million due primarily to an unrealized loss of $1.9 million on the cash surrender value of life insurance investments held for certain benefit plans compared to an unrealized gain of $2.6 million in 2010 which was partially offset by a $0.5 million reduction of costs associated with evaluating new business opportunities in 2011 compared to 2010. Diluted earnings per share was $0.90 in 2011 and 2010.

        The 2009 GRC and corresponding approved rates will increase 2012 and 2013 revenues (see discussion in Regulatory Matters section of this annual report).

        We plan to continue to seek rate relief to recover our operating cost increases and receive reasonable returns on invested capital. We expect to fund our long-term capital needs through a combination of debt, common stock offerings, and cash flow from operations.

Critical Accounting Policies and Estimates

        We maintain our accounting records in accordance with accounting principles generally accepted in the United States of America and as directed by the Commissions to which our operations are subject. The process of preparing financial statements requires the use of estimates on the part of management. The estimates used by management are based on historic experience and an understanding of current facts and circumstances. A summary of our significant accounting policies is listed in Note 2 of the Notes to Consolidated Financial Statements. The following sections describe those policies where the level of subjectivity, judgment, and variability of estimates could have a material impact on the financial condition, operating performance, and cash flows of the business.

Revenue Recognition

        Revenue generally includes monthly cycle customer billings for regulated water and wastewater services at rates authorized by regulatory Commissions (plus an estimate for water used between the customer's last meter reading and the end of the accounting period) and billings to certain non-regulated customers at rates authorized by contract with government agencies.

        The Company's regulated water and waste water revenue requirements are authorized by the Commissions in the states in which we operate. The revenue requirements are intended to provide the Company a reasonable opportunity to recover its cost of service and earn a return on investments.

        For metered customers, Cal Water recognizes revenue from rates which are designed and authorized by the CPUC. Under the Water Revenue Adjustment Mechanism (WRAM), Cal Water records the adopted level of volumetric revenues, which would include recovery of cost of service and a return on investments as established by the CPUC for metered accounts (adopted volumetric revenues). In addition to volumetric-based revenues, the revenue requirements approved by the CPUC include service charges, flat rate charges, and other items not subject to the WRAM. The adopted volumetric revenue considers the seasonality of consumption of water based upon historical averages. The variance between adopted volumetric revenues and actual billed volumetric revenues for metered accounts is recorded as a component of revenue with an offsetting entry to a regulatory asset or liability balancing

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account (tracked individually for each Cal Water district) subject to certain criteria under the accounting for regulated operations being met. The variance amount may be positive or negative and represents amounts that will be billed or refunded to customers in the future.

        Cost-recovery rates are designed to permit full recovery of certain costs allowed to be recovered by the commissions. Cost-recovery rates such as the Modified Cost Balancing Account (MCBA) provides for recovery of adopted expense levels for purchased water, purchased power and pump taxes, as established by the CPUC. In addition, cost-recovery rates include recovery of cost related to water conservation programs and certain other operation expenses adopted by the CPUC. Variances (which include the effects of changes in both rate and volume for the MCBA) between adopted and actual costs are recorded as a component of revenue, as the amount of such variances will be recovered from or refunded to our customers at a later date. There is no profit associated with cost-recovery expenses which are generally recognized when the expenses are incurred.

        The balances in the WRAM and MCBA assets and liabilities accounts will fluctuate on a monthly basis depending upon the variance between adopted and actual results. The recovery or refund of the WRAM is netted against the MCBA over- or under-recovery for the corresponding district and is interest bearing at the current 90 day commercial paper rate. When the net amount for any district achieves a pre-determined level at the end of any calendar year (i.e., at least 2.5 percent over- or under-recovery of the authorized revenue requirement), Cal Water files with the CPUC to refund or collect the balance in the accounts. Account balances less than those levels may be refunded or collected in Cal Water's general rate case proceedings or aggregated with future calendar year balances for comparison with the recovery level. Cal Water excluded net WRAM and MCBA operating revenue of $12.9 million, associated costs of $10.5 million, and the related $2.4 million of net operating income before income taxes as of December 31, 2011 due to the net receivable balance estimated to be collected more than 24 months. The net WRAM and MCBA revenue and associated costs were determined using forecasts of rate payer consumption trends in future reporting periods and the timing of when the CPUC will authorize Cal Water's filings to recover unbilled balances. The deferred revenue and associated cost amounts will be recorded in future periods as the collection becomes within twenty-four months of the respective reporting period.

        The net WRAM and MCBA balances included in regulatory assets and liabilities as of December 31, 2011 and 2010 are: