Cobb County Government
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Sewer System Extension

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While Cobb County has a very extensive infrastructure in place for wastewater collection and treatment, there are still some locations in the county where sewer service is not available. These areas may be undeveloped properties, but most often consist of existing residences or even entire subdivisions that rely on individual septic tanks for on-site wastewater management. Acknowledging that the extension of sewer lines to un-served areas must be addressed in a consistent and proactive manner, the Cobb County Water System’s Sewer Extension Policy was developed. The objectives of this policy are to:

  1. Establish conditions under which the Water System will provide for the construction of sewer extensions;
  2. Address funding issues related to the construction of sewer extensions; and,
  3. Define a mechanism for the provision of sewer service to existing developed areas which have inadequate wastewater handling facilities.

In some cases, sewer extensions may be planned construction based on needs or priorities identified in the Water System’s Sewer Master Plan and programmed into the adopted Capital Improvement Plan. At times, extensions may be associated with new development in areas where sewer service is currently unavailable. These situations usually result in new sewer lines being constructed at the cost of the developer, with possible limited participation of the Water System if circumstances warrant. The participation by the County in development-related projects requires the execution of a Planned Development Agreement to confirm the terms and cost-sharing arrangements.

Frequently, sewer extension construction projects are initiated based on the request of a group of homeowners that are experiencing failure of their septic tank systems. If minimum participation percentages are met on the petition, if sewer service is technically feasible, and if financial criteria are satisfied, then an extension project will be developed to meet the needs. The cost of construction of the new sewer system will be shared by the Water System and the residents that will be served. The resident’s share will be comprised of a Sewer Extension Fee, as well as the standard Sewer Development Fee. In addition, each resident will incur costs for a plumbing company to install the service line from the house to the sewer tap at the street.