Current wastewater system may not be suited for new complex

By Joel Davis
of The Daily Times Staff

An alternative wastewater treatment technology currently being used in Blount County is safe but may not be appropriate for a proposed sports complex on Highway 411 South, according to experts.

Sand filtration systems, which use microorganisms to consume pollutants and then disperse the treated water through an underground system of drip tubes, allow developers to place homes in areas where traditional septic drain fields cannot be used.

Businessman Jerry Simmerly has planned to use a sand filtration system to service a 230-acre sports complex proposed for a location on U.S. 411 South just south of Henry Lane.

Gregory Reed, head of the Civil and Environmental Engineering Department at the University of Tennessee, has questioned the use of a sand filtration system for a project on the scale of the proposed sports complex.

"They are safe systems if they are installed and monitored properly and are in proportion to the source of the wastewater coming in," he said. "What was described to me was the potential for the development to have motels and multiple other facilities that might end up having a fairly large number of people as users. I would be a little bit concerned."

Gary Ferguson, Director of the Blount County Environmental Health Department, said the sand filtration technology is safe.

"That is a West Coast technology that has been around 25 to 30 years," he said. "If they are maintained properly, they are good systems. They are basically like a mini-sewer plant."

John R. Buchanan, who directs the University of Tennessee Center for Decentralized Wastewater Management, said there are already sand filtration systems in place locally.

"Like it or not, many condos and vacation homes that are up on the mountains in Sevier County and Blount County use these technologies," he said.

Sand filtration systems can allow bigger subdivisions to be built than developments using traditional septic tank systems.

Communities need to be aware of how this can affect other infrastructure needs, such as providing adequate schools, Buchanan said.

"Those are the issues that arise from all of the sudden being able to treat wastewater and now put three houses on one acre," he said. "Those are the issues that have really jumped up and bit Rutherford County in the hind end. They are building schools so fast. Even getting electricity out to those places is interesting."

Good community planning is the best approach in dealing with these issues, Buchanan said.

"Don't outlaw the (sand filtration) wastewater treatment system," he said. "Use good zoning rules."

According to Tisha Calabrese-Benton, Deputy Communications Director for the Tennessee Department of Environment and Conservation, the state requires the sand filtration systems to be carefully monitored.

Although sand filtration systems can allow more houses to be built than with traditional septic tank systems, the size of developments are still dictated by the amount of suitable land available for the specific wastewater systems.

"One rule of thumb for rough planning purposes is to assume that an acre with good soil can take 8,000 gallons per day," she said.

The most common capacity for systems approved by the state is 35,000 gallons per day, which can serve about 100 homes, Calabrese-Benton said.

The sand filtration systems are also expensive. Subdivision developers will often add $5,000 to $6,000 to the price of individual lots to pay for the system, according to Buchanan.