Cobb County Government

Procedures And Reporting

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Any active current industrial, commercial, or institutional user ("User") of the Cobb County Water System is eligible for a credit on wastewater service charges for metered water which is not returned to the sewer system.

Procedures and Reporting

The following paragraphs describe the application procedures for potential participants in the Wastewater Retainage Credit Program and the requirements for periodic reporting of water use and returns to the sewer.

  1. The applicant must contact the Water System’s Chief Engineer (or designee) to discuss the basic requirements of the program, its applicability to particular situations, typical metering arrangements, reporting, and other pertinent information.

  2. The User must retain the services of one of the approved independent engineering firms to develop a location plan for sub-meters, along with a meter-reading schedule, and to prepare the semi-annual Retainage Analyses. The User is required to pay all costs associated with the engineer’s services, the installation and maintenance of sub-meters, and other related work.

  3. Sub-meters shall be installed to measure make-up water, water used in a product, boiler supply water, or other consumptive uses. Also, sub-meters are required on blow-downs, overflows, or product waste streams to measure the return from these sources to the sewer system. The difference in readings between the supply and return sub-meters will reflect the “retained” amount. All meters shall be calibrated annually to maintain accuracy.

  4. The readings of the sub-meters must be recorded by the User on a monthly basis, consistent with the Water System’s meter-reading schedule and billing cycle for the customer. The User may also read and record the Water System meter at the same time the sub-meters are read, if desired for coordination of data recording intervals; however, the billing records will govern if there is a discrepancy in readings. If a consistent monthly usage can be demonstrated (after at least two full seasonal periods), the frequency of readings can be reduced to two per season.

  5. All meter readings are compiled and compared to the User’s total water consumption in a Retainage Analysis report that is prepared by the engineering firm. A “Percentage of Water Returned to Sewer” value will be calculated in each Retainage Analysis report and the long-term average will be shown on the Retainage Analysis Summary Form. This percentage will be applied to the User’s wastewater commodity charge in each water bill for a six month period. The long-term average will be recalculated with each subsequent seasonal analysis, using the current period data along with the data for that period from the three previous years of the User’s participation in the program.

  6. The Retainage Analysis, bearing the seal of the preparing professional engineer, is submitted to the Water System twice a year. The report may be in any form deemed suitable by the preparer, as long as it is sufficiently detailed to allow verification of water consumption and return flows.

  7. The seasonal periods, schedule for submittal, and effective dates for credits follows:

    Seasonal Period Submittal Due Date* Credit Effective Date
    April 1 – September 1 February 1 May 1
    October 1 – March 1 August 1 November 1
    * Submittal is due on the first business day following the date indicated.

  8. If it is determined that no significant seasonal variation occurs in the percentage of water returned to the sewer, the Water System may, upon request of the User, elect to waive one of the two annual submittals.

  9. If a new Analysis is not received by the submittal date as required, the User’s credit will be eliminated on the seasonal Effective Date.

Click here to view and download a sample of the Analysis Form alt

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