First Utility District of Knox County

FIRST UTILITY DISTRICT USES TECHNOLOGY TO STAY

Clean water and sanitary sewer service are often taken for granted by the general public.

But for the employees at First Utility District (FUD) of Knox County, Tennessee, every one of the 13,299 manholes in their coverage area reminds them of one of their indispensable roles: taking care of the waste water pumped through approximately 600 miles of sewer lines.

While the district is responsible for both providing drinking water and collecting wastewater, it is FUD’s success with the sewer rehabilitation program that makes general manager Bruce Giles beam.

He also credits FUD’s board with fiscal savvy. The district has spent about $9 million on sewer rehabilitation so far, and is budgeting $45 million for the program over the next five years— and that’s in cash. This responsible planning—both in the financial sense and with the intensive rehabilitation program—has resulted in lower fees for customers, Giles says.

“Proof is in the numbers, and I believe we have the best program in East Tennessee,” he says.

PROACTIVE APPROACH

The district’s proactive approach to maintaining and rehabilitating the sewer lines also involves fixing manholes and replacing the system’s most crucial element, pump stations.

“We’ve been replacing a pump station every year,” Giles says. “Thirty or 40 years ago, nobody thought about this,” he adds, noting that the district has grown from the small area of 3,000 people that it first served, to a much larger area serving 100,000 residents.

Since 1974, the plant has upgraded its capacity from one million gallons per day to 18 million gallons per day to meet the growing demand for more capacity.

First Utility District is based in West Knoxville, the fastest growing portion of the Knoxville metropolitan area. As part of its planning process, the district is taking anticipated future growth into consideration.

BACKUP POWER ESSENTIAL

To serve the growing number of households and businesses, FUD has taken the necessary steps to employ critical backup measures. Every major system within the district has backup power, and the Tennessee Department of Environment and Conservation recommends that any facility handling one million or more gallons per day have a generator set. Should a pump stop working or even not be working up to par, heavy rains or other disasters could cause backups and overflows with devastating results.

“With summertime storms, or storms in general, we need our pump stations to stay in service, or we will have sewers overflowing,” says Pat Spangler, director of capacity management operations and maintenance. “When we get these heavy rains, at some of our bigger stations it is critical that we are not out of service for any length of time, especially during off hours, at night.”

A sewer overflow in the Fort Loudoun Reservoir means that FUD has to file a report with the Tennessee Dept. of Environment and Conservation saying what occurred, and take samples for sediment and pathogens.

“One of the things that all large wastewater systems strive for is to ensure that we don’t have sewer overflows during an outage, because it can take us to another level in terms of violating the Clean Water Act,” Giles says.

A few years ago, the district experienced 70 or more sanitary sewer overflows a year. So far this year, the district’s sewer overflows tally just eight.

For the past five years, the FUD wastewater plant has earned the Operator Excellence Award for the State of Tennessee. The award stems from operational efficiencies and no violations of the district’s discharge monitoring permit during each of those 12-month periods.

Each pump station has multiple water pumps, and the station has to be able to handle the flow even if its largest pump is out, says operations project manager Brad Brummett.

The generator sets are set up with an immediate response in case of power failure, because if the pumps stop for just a few seconds, it can result in loss of pressure and serious water hammer.
Powerful pumps are pushing thousands of gallons of water out per hour, and if the pumps stop, the water flows backwards. When they start again, the pressure on the pumps is intense, hence the term water hammer.

“You don’t want that,” Spangler says. “Water hammer can break things.”

The diesel-powered generators are set up to automatically run under load for an hour every week, including a 15-minute cool down cycle. Every pump station gets a weekly maintenance check, and all generators undergo annual load bank testing.

Besides ensuring there is a reliable source of back-up power, FUD also stays prepared for the worst through regular, intensive maintenance. This was not always the case, Giles said.
“We have 80 square miles of service area that used to leak like a sieve. It had all sorts of leaks of groundwater and we had to slow down the amount of groundwater getting in our waste,” he said.

Those instances of inflow and infiltration have been greatly reduced as leaks are repaired and old sewer lines replaced. Rather than arbitrarily replacing lines, though, FUD uses a robotic camera that crawls the sewer lines and provides a view of the lines and potential problems.

On any given day, the camera crew can be seen around FUD’s coverage area, with their CCTV camera dropped down a manhole. Inside the crew’s truck, an employee directs the camera, pausing to look at problem areas and to take pictures and notes.

Though the camera can be used when a problem is suspected, the majority of the time it is simply preventive maintenance. For the same reason, pipes are cleaned every 3-5 years – a frequency not seen at most sewer districts.

But, as Spangler stressed, pipes will continue to get older with each passing day and the district intends to persist in its progressive program.
“It’s all about getting the right people, right tools and right equipment and doing it right,” said Spangler. “We’re not going to let up, we’re going to keep being aggressive.”

WANT TO LEARN MORE?

This story appeared in the September/October issue of Tennessee Public Works magazine, a regional magazine for local governmental organizations, municipalities and utility districts. Download the story as it appeared in the magazine.

Visit First Utility District’s website to learn more about the services the company provides.