Two separate issues before two different regulatory agencies related to water quality in the Chattahoochee River at Peachtree Creek are getting significant public attention. The first is an Environmental Protection Division-proposed change to Georgia’s Water Quality Standards (the Rule), presently pending before the Board of Natural Resources. The proposed change would remove a footnote to water quality standards that dates from the mid-1970s. At that time, this footnote was perceived to provide some comfort to municipal and industrial wastewater dischargers that allocations of allowable waste load would be based on a flow in the Chattahoochee River at Peachtree Creek of 750 cubic feet per secondtaken from the operating parameters used by the U.S. Army Corps of Engineers in its regulation of the flows in the river.
The 1970s-era water quality in this reach of the Chattahoochee was far from the quality that it is today. No longer does the river violate the water quality standard for dissolved oxygen 64 percent of the time as it did in years 1968-1974. While some think that this footnote requires that flows remain at least 750 cubic feet per second at Peachtree Creek, it actually does not guarantee any flow and is not a flow standard under the Clean Water Act. Rather, what sets the flow at Peachtree Creek is the Corps’ Water Control Manual, which is presently undergoing an intensive review and update.
Any proposed change in the flow target must be evaluated in conjunction with a number of other operational aspects of the Water Control Manual. The Corps should examine a lower flow target at Peachtree Creek for the cool, wet months of the year using the most current water quality data. I am optimistic that there is a safe, lower flow target for Peachtree Creek to conserve water in the winter and spring, which will be needed later during the summer and fall and during periods of prolonged drought. That optimism is based not only on water quality modeling of current conditions, but on actual adjustments the Corps has already made to the flow target during the winter and spring months over the last several droughts. Each time, water quality was maintained at 650 cubic feet per second.
No one is advocating or even discussing the prudence of lowering the 750 flow target at Peachtree Creek during the hot, dry months. Any adjustment in the flow target for the winter and spring months, however, will be set through the open and transparent process of updating the Water Control Manual. The EPD-proposed amendment to its water quality standards will not alter the actual flow target at Peachtree Creek. The state should amend its Water Quality Rule as proposed, if for no other reason than to clarify that this footnote does not provide the guaranteed flow that some believe it does. More importantly, however, stakeholders should prepare to examine and comment on the Corps’ draft Water Control Manual due for release this fall. Together I believe we can find that optimal operating flow target for Peachtree Creek.
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