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Exhibit 12.1

California Water Service Group
Computation of Ratios of Earnings to Fixed Charges
(In thousands except ratios)

 
  Year ended December 31,  
 
  2011   2010   2009   2008   2007  

Earnings:

                               

Income before Income Tax Expense

  $ 60,878   $ 62,211   $ 67,916   $ 63,936   $ 51,882  

Fixed Charges Interest Expense

    32,455     27,936     24,394     20,591     19,719  

Capitalized Interest

    (2,741 )   (1,563 )   (3,081 )   (3,411 )   (2,585 )
                       

Total

  $ 90,592   $ 88,584   $ 89,229   $ 81,116   $ 69,016  
                       

Fixed Charges:

                               

Interest Expensed &Capitalized, & amortization of capitalized expense related to indebtedness

  $ 32,455   $ 27,936   $ 24,394   $ 20,591   $ 19,719  

Estimated Interest Component of Rent Expense

    474     338     329     237     221  
                       

Total

  $ 32,929   $ 28,274   $ 24,723   $ 20,828   $ 19,940  
                       

Ratio of Earnings to Fixed Charges

    2.75     3.13     3.61     3.89     3.46  



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California Water Service Group Computation of Ratios of Earnings to Fixed Charges (In thousands except ratios)