Murfreesboro’s population grew by 2,250 people last year, according to the U.S. Census, and, though down from previous years Murfreesboro Water and Sewer Department has struggled to keep up. In a little over four years, an upgrade to MWSD’s wastewater treatment plant will allow it to process over half again as much waste water coming into the plant, MWSD Director Darren Gore said, or from 16 million gallons per day to 24 million gallons per day
Once the project is complete, it will have cost $36 million, he added. To fund it, ratepayers are being charged $3 per month per customer over the next five years. “We just got it approved for design Nov. 8,” Gore said. “We’re looking at 15 to 18 months for the design phase and two and a half to three years for construction.”
Population growth is the most urgent reason for having to upgrade, Gore explained. Tennessee Department of Environment and Conservation (TDEC) rules limit the amount of wastewater that can be processed to 80 percent of the plant’s capacity, which is 16 million gallons a day. “We’re just reacting to the growth we’ve had and planning for the future growth,” Gore said. Unlike the high-technology membrane filtration system installed in the latest upgrade at the City’s water treatment plant off Sam Jared Drive behind the Veterans Administration Medical Center in northern Murfreesboro, construction will primarily duplicate existing processes that have proven successful over time, said Assistant Wastewater Treatment Plant Superintendent Stan Wallace, a veteran of 37 years with the City of Murfreesboro. “While we always look at new technology, it isn’t always a good idea to change from a proven process in this business,” Wallace said.
As elaborate as the multi-million dollar add-on will be, Gore admitted, the upgrade is likely to only address a 10- to 15-year event horizon, and, to a large extent, even that will depend on the rate of population growth.
That creates another hitch – how to get rid of the near-potable water the treatment plant produces.
A large portion goes back into the West Fork of the Stones River at the plant’s discharge point, Gore explained, but, the Tennessee Department of Environment and Conservation has branded this section of Murfreesboro’s waterways as impaired. That means only so much treated water can be returned to the river, even if it is far better quality than what is there naturally. An ingenious system of a half-million-gallon holding tank to supply spraying a portion of it onto two large farms acquired mainly for the purpose takes care of part of it, he said, and an even more ingenious water re-use program irrigates nearly every corner of the Gateway District, The Avenues and other locations, including a few residential properties.
However, he cautioned, if growth continues and unless new ways of ridding the city of its effluent are found, Gore says, there will eventually be a point at which new sewer connections may be significantly hindered.
At that point, he said, the city will face buying more land or finding another stream or river into which the city can discharge its wastewater. Gore noted the department is working diligently with TDEC to come up with creative and progressive ways to dispose of this highly treated water.
Meantime, Gore has said it is his goal to keep the City moving forward in the “business as usual” fashion the City has grown accustomed to; where there are no concerns about new developments being afforded sanitary sewer services. For now, though, Gore says the increase in capacity at the waste water treatment plant on Blanton Drive should serve Murfreesboro’s needs for the next 10 to 15 years.