Harpeth River does not meet state Water Quality Standards in the summer. Reduction in Discharges from Sewage Treatment Plants needed in order to increase oxygen levels in the river.
Why the Harpeth River is not Meeting
Water Quality Standards in the summer:
Do you enjoy swimming, paddling, tubing, fishing, and playing on the Harpeth River? No matter where your favorite spot is along the main Harpeth, from the headwaters in Eagleville down 90 river miles to the Harpeth River State Park in Cheatham County, the river does NOT meet water quality standards during the summer. TDEC counted close to 300,000 people who visited just the highly popular Harpeth River State Park in 2010.
In 2010, for the first time, the 3 state sewage treatment plant permits that serve all the growth in Franklin and northern Williamson County were revised simultaneously as a step toward reducing pollutant load into the river. While some aspects of the proposed permits are tighter, they still allow twice as much pollutant load than the river can handle in order to meet state water quality standards based on analysis done by the EPA.
IMPORTANT UPDATE APRIL 2012: City of Franklin's Consultants propose long-term sewer and water plan that does not improve water quality in the Harpeth.
BACKGROUND: The Harpeth River in the summer is “effluent dominated."
For over a decade, studies by the EPA, TDEC, HRWA and others, have recorded oxygen levels in the river water well below state standards. Dissolved oxygen levels in the river water have been recorded at less than half the state standard of 5 mg/l and even lower, at levels that stress fish which have trouble breathing and feeding and will not reproduce. See two charts below that show TDEC data and HRWA results from our 2006 Dissolved Oxygen study. (This report includes all D.O. data from TDEC and EPA up to this year. More recent studies from 2007 and 2008 are in a separate report.) Pollutants from sewer plant discharges, septic seepage, and urban and agricultural runoff feed the growth of algae and bacteria that cause the water’s oxygen levels to drop very low and give the river a green color when in healthier conditions it would be clear.
The largest pollutant sources are the sewer plants that serve Franklin and Northern Williamson County that discharge into the Harpeth in one 17 mile stretch (Franklin, Lynwood that serves Cottonwood, and Cartwright Creek that serves River Rest). The largest sewer plant in the entire river system is the city of Franklin’s with a design capacity of 12 million gallons per day (12MGD). In comparison, the flow in the Harpeth in downtown Franklin can be as little as only 1/2 million gallons per day. This is the extreme low flow condition for the Harpeth that the sewer permits are supposed to be designed to protect. The other two sewer plants are much smaller (each around ½ million gallons a day), but still large enough to affect the river’s water quality as seen in the river dissolved oxygen studies and discussed in a water quality analysis funded by HRWA.
Steps to Improve sewer issues have been started:
Over ten years ago, poor water quality conditions and past sewer plant problems in the Harpeth River have been the focus of concerned citizens who felt compelled to sue in years past that led
to the EPA’s pollutant load reduction plan (known as a TMDL) for the Harpeth in 2004 and improvements with Lynwood that was violating its permit under prior owners. In recent years, Williamson County, Franklin, TDEC, and the current sewer plant operators have all invested in efforts that will improve water quality. Williamson County led the way to hook up the neighborhoods on septic that were experiencing failures around Lynwood and northern Franklin to central sewer. TDEC helped this effort by reserving half the new capacity of Lynwood for these neighborhoods when they approved that plant’s expansion. Now these areas will be treated by Franklin which has a much more efficient system. Franklin built a new plant that produces very clean effluent, well below its current and proposed permit limits, and is only at half capacity. In addition, the city has been forward thinking in developing alternatives for discharging treated effluent with its effluent reuse program. This means the city discharges only half of its effluent in the summer into the Harpeth, while the rest is used to irrigate several golf courses. Franklin’s set a goal to reduce its effluent discharge into the Harpeth in the city’s Sustainability Action Plan. And it has launched the previously mentioned regional water and sewer plan.
HRWA's GOAL FOR THE HARPETH RIVER: Meet Water Quality Standards and Maintain Natural River Flows
Final permits were issued in October 2010 and will be up for renewal in Novemeber 2011. For further information contact Gary Davis, Gary.Davis@tn.gov , (615) 532-0649, at TN Department of Environment and Conservation.
Comments submitted by the HRWA and Dissolved Oxygen Studies are all accessible in the Library of this web site. HRWA comments to TDEC on the revised permits: December 2009, and additional comments for the public hearing in August 2010.
Not all of the attachments to HRWA's comments nor comments submitted by other entities are on this web site. If you would like these documents, please contact, Dorene Bolze, Executive Director.
This story is on WSMV.com.