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    <Log type="Info">'Monetary' elements on report '2420403 - Disclosure - Aquisitions Pro Forma Summary for Prior Year (Details)' had a mix of different decimal attribute values.</Log>
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    <Log type="Info">Process Flow-Through: 1001000 - Statement - CONSOLIDATED BALANCE SHEETS</Log>
    <Log type="Info">	Process Flow-Through: Removing column 'Dec. 31, 2010'</Log>
    <Log type="Info">	Process Flow-Through: Removing column 'Dec. 31, 2009'</Log>
    <Log type="Info">Process Flow-Through: 1001501 - Statement - CONSOLIDATED BALANCE SHEETS (Parenthetical)</Log>
    <Log type="Info">Process Flow-Through: 1001502 - Statement - CONSOLIDATED BALANCE SHEETS (Parentheticals)</Log>
    <Log type="Info">Process Flow-Through: 1003000 - Statement - CONSOLIDATED STATEMENTS OF INCOME</Log>
    <Log type="Info">	Process Flow-Through: Removing column '3 Months Ended
Dec. 31, 2012'</Log>
    <Log type="Info">	Process Flow-Through: Removing column '3 Months Ended
Sep. 30, 2012'</Log>
    <Log type="Info">	Process Flow-Through: Removing column '3 Months Ended
Jun. 30, 2012'</Log>
    <Log type="Info">	Process Flow-Through: Removing column '3 Months Ended
Mar. 31, 2012'</Log>
    <Log type="Info">	Process Flow-Through: Removing column '3 Months Ended
Dec. 31, 2011'</Log>
    <Log type="Info">	Process Flow-Through: Removing column '3 Months Ended
Sep. 30, 2011'</Log>
    <Log type="Info">	Process Flow-Through: Removing column '3 Months Ended
Jun. 30, 2011'</Log>
    <Log type="Info">	Process Flow-Through: Removing column '3 Months Ended
Mar. 31, 2011'</Log>
    <Log type="Info">Process Flow-Through: 1004000 - Statement - CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME</Log>
    <Log type="Info">Process Flow-Through: 1004501 - Statement - CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Parenthetical)</Log>
    <Log type="Info">Process Flow-Through: 1005000 - Statement - CONSOLIDATED STATEMENTS OF RETAINED EARNINGS</Log>
    <Log type="Info">Process Flow-Through: 1006000 - Statement - CONSOLIDATED STATEMENTS OF CASH FLOWS</Log>
    <Log type="Info">Process Flow-Through: 1006501 - Statement - CONSOLIDATED STATEMENTS OF CASH FLOWS (Parentheticals)</Log>
    <Log type="Info">Process Flow-Through: 1009500 - Statement - CONSOLIDATED STATEMETS OF INCOME (Parentheticals)</Log>
  </Logs>
  <InputFiles>
    <File>ctws-20121231.xml</File>
    <File>ctws-20121231.xsd</File>
    <File>ctws-20121231_cal.xml</File>
    <File>ctws-20121231_def.xml</File>
    <File>ctws-20121231_lab.xml</File>
    <File>ctws-20121231_pre.xml</File>
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  <HasPresentationLinkbase>true</HasPresentationLinkbase>
  <HasCalculationLinkbase>true</HasCalculationLinkbase>
</FilingSummary>
