Long-Term Drought Solutions in Georgia: Sewage into Wetland into Reservoir into Drinking Water

One of seven proposals for dealing with the next Georgia drought (Hollabaugh, 2008) is to treat sewage as a source of drinking water. One way this can be done is by high-technology treatment of sewage so that it is reprocessed to meet EPA standards. A second low-cost and low technology treatment of sewage is cycling treated sewage through a succession of wetlands into a drinking water reservoir.

A recent example of the high-tech and high-cost treatment is the $490 million groundwater replenishment system of Orange County Water District, California that was approved in January 2008 for injection of 35 million gallons/day (MGD). Future approval will allow 35 MGD of treated sewage to percolate into groundwater. Georgia's Clayton County Water Authority (CCWA) has a low-cost and low-tech system that sends treated sewage through ponds and wetlands. The system cost half as much as a regular sewage plant and returns 10 MGD to drinking water reservoirs. During the Georgia drought of 2007, Clayton County drinking reservoirs remained full.

In north Georgia there are 12 new reservoirs in stages of permitting/construction. They range in size from <300 to 2,300 acres. Many are pump storage reservoirs. Our research focuses on determining the addition to drinking water supply from a CCWA system for these twelve reservoirs and 16 existing reservoirs. Limitations to using this type of system in north Georgia include widespread septic systems, small rural towns with small sewage treatment plants, lack of available land for the wetlands system, and public resistance to drinking treated sewage. Results show that some rural counties would benefit little from the CCWA system. However other counties with large population could benefit from the CCWA system. This system needs too much land to work for metro Atlanta; however the high-cost high-tech process may be used.