Distribution System Sets a High Standard

Award-winning utility takes an efficient approach to system upgrades and operation.

Distribution System Sets a High Standard

Shawn Thompson (left) and senior pump maintenance mechanic Scott Brumley position a replacement pump for installation.

Mooresville (North Carolina) Public Utilities earned the state’s Distribution System of the Year award three years in a row from 2014-16. The run ended in 2017.

“I don’t know what happened,” says a laughing Allison Kraft, director of Public Utilities for the western North Carolina community. “But … we also won the American Water Works Association Collection System of the Year award in 2013, 2016 and 2017.”

And to no one’s surprise, they reclaimed their place as Distribution System of the Year in 2018.

Obviously, Mooresville utilities are in good hands even when the system occasionally is not feted for excellence. Some of the credit must go to Kraft. She has been in Mooresville for a dozen years and, prior to becoming utilities director last year, headed the town’s engineering department.

Growth rates

Mooresville’s population doubled between 1990 and 2000, from 9,300 residents to 18,800. In the 18 years since, it has doubled again, with approximately 40,000 people now calling the city home.

“It definitely is a struggle to stay ahead of the growth,” Kraft says. “We are doing fine right now, but we have a lot of capital projects coming on to increase the backbone of the system.” The city’s five-year capital improvement program has a $40 million price tag, with much of it pegged to growth-related large-scale maintenance projects.

Kraft says rates have been “relatively high” for years after a visionary board saw growth coming and prepared for it. “They made the decision at that time to set the rates relatively high and pay for construction and maintenance costs as we went. They looked far ahead and, consequently, we were able to meet the capital costs to maintain our growth.” Mooresville’s rates are now nearer the regional norm after other cities in the Piedmont region raised rates to play catch-up with infrastructure.

The other impact of all the capital projects is that the city has difficulty finding contractors. It is a problem Mooresville shares with other communities in the greater Charlotte area. “Sometimes we have projects we really want to do, but the construction climate is very competitive in favor of contractors,” the utilities director says. “We’ve had to make some decisions, prioritizing projects that are in the best interests of ratepayers so we can get them done.”

Ample supply

The Mooresville wastewater system serves 16,000 accounts and includes more than 600 miles of waterlines and sewer lines, 50 lift stations and 6,500 manholes. That infrastructure needs constant attention and in the last year, Kraft says more than 1.5 miles of gravity lines were rehabbed or replaced, 25 miles of sewer line inspected, 10 manholes repaired, 84 miles of sewer and 18 lift stations cleaned, and 132 troubleshooting or emergency responses made.

Thirty-two people in the water and sewer maintenance department do all this work, save for larger projects that are outsourced. Some of the crews are dedicated to specific tasks such as pump maintenance, meter reading, utility locating and electrical maintenance. “The rest of our crews are really interchangeable and cross-trained,” Kraft says. Though generally assigned to either water or sewer utilities, they can switch from one to another as tasks demand, including being on call for emergencies on weekends.

It helps that most of the community’s water and sewer infrastructure is relatively young. Mooresville’s wastewater treatment plant on the Rocky River was built in the 1980s and was expanded and upgraded in 2011.

The city’s two water plants are capable of pumping significantly more volume than current demand requires. The newest plant, with a capacity of 12 mgd, was commissioned in 2010. “The plant was built so we can double its size by adding parallel filters. It was built when growth was on the horizon,” Kraft says. The older unit, which dates from the 1960s, underwent a major renovation in the 1990s and has a capacity of 6 mgd.

Water is plentiful: Mooresville’ supply is drawn from Lake Norman — built by Duke Energy and considered the largest man-made freshwater body in North Carolina. The oldest section of Mooresville — its downtown area — contains the most suspect pipes, but they are being methodically replaced. In several areas of the city, 2-inch galvanized waterlines are being supplanted by PVC lines.

Current focus

Monitoring the condition of gravity sewer system is the preoccupation of two employees, who systematically inspects the lines. He probes the pipes using an Envirosight ROVVER X camera, with images uploaded using WinCan software.

The inspections help guide the work routine of the pipeline maintenance crew, while other crews concentrate on other tasks. The pump station crew systematically keeps water moving. Water crews install new water meters seemingly just ahead of moving vans plying the fast-growing Charlotte suburb. The pipe-cleaning crew spends a significant amount of time trying to stay ahead of the verdant region’s many tree roots, which constantly infiltrate sewer systems.

Maintenance crews do one waterline replacement job a year, usually less than 500 feet in length. “It’s a way to maintain some skills,” Kraft says. The rest of the new or replacement construction work is bid out. Currently some $12 million of large-diameter PVC sewer outfall pipeline projects are being worked by contractors and two other projects are in the design stage. The new infrastructure will increase capacity, replace some aging lines and extend services to unserved areas.

“So far, we have only replaced pipe in the traditional manner,” Kraft says. A current focus is replacement of 2-inch pipe with 8-inch pipe. “We haven’t had the opportunity to try bursting pipe. We haven’t had a project that was a good candidate for that process.”

Most excavation is handled with traditional equipment. Though maintenance crews do have access to two Vacall vacuum trucks — one just 3 years old — neither is configured for hydroexcavation. “Though we sometimes do use the trucks like a hydroexcavator,” she says, applying high-pressure water with a wand and sucking up the solution. Any other equipment Kraft needs for a maintenance project she can acquire by walking down the hall of the operations center to the streets department office. “We always can borrow from them.”

Efficient management

The operations center, which opened in 2011, is key to the city’s effective utility management. The building houses utilities maintenance, sanitation and street department staff, and the engineering department; and Kraft believes the grouping of departments is a big plus.

“No one anticipated the benefit from a workflow standpoint that coming together in that building was going to give us,” she says. “You can walk right down the hall and coordinate waterline work with sidewalk work. I can coordinate with the street program so we can get ahead of them on utility projects. From a workflow perspective and public perception standpoint, no one wants to see a utilities cut in a brand-new road.” 

The other impetus behind the utilities department functioning with such award-winning efficiency is the adoption of GIS mapping. It came about when the economy tanked in 2008-09, Kraft says, leaving staff in the engineering department with little to do. “People wanted to find something meaningful for them to do, so they were taught, for example, how to pick up locations of meters using hand-held GPS units and to scan old drawings and input them into the system. Without too much help from outside consultants, we created a GIS system and we use it extensively now.”

She says the system required a half-dozen years to actually become useful and still is a work in progress. “But now we have it to where we can put a work order in the system, or track where we have had sewer backups, or work with the wastewater plant to track down the source of something found in the system.”

In short, the GIS combined with improved interdepartmental coordination spawned new ways for Mooresville to stay ahead of utilities issues. The city’s proactive maintenance, lessened water loss, improved handling of pipeline issues, and similar management successes are the result — all of which impresses judges when awards are being handed out.

“I don’t feel pressure to win awards, but we continually are looking for ways to our work better, looking at new equipment, at new ways of doing things,” Kraft says. “I’m really proud that we are not afraid to try something, but also are willing to say, ‘No, this didn’t work for us. Let’s try something else.’ If it’s not the right thing, we move on.”

Evolution of a city’s economy

Mooresville began as a farming community in the 1700s. It prospered at the turn of the 20th century on the strength of large cotton plantations that fed product to cotton mills. The city’s large Mill No. 1 became a self-contained village within a community, with housing, churches, schools and stores provided for employees by the mill owners.

Allison Kraft, Mooresville utilities director, is well aware of this history. Her office is saddled with updating the sewer and water infrastructure in the downtown’s Historic Mill Village. “The lines were laid by the owner of the mill and eventually turned over to the city,” she says. “We are in the midst of a project to replace all of them.”

While the largesse of the mill owner was appreciated at the time, private development of the water and sewer systems now poses difficulties for the city. There are no schematics for the systems, for instance. “We don’t have any map of many of the pipelines. That’s the struggle for us,” Kraft acknowledges. Tracking down and replacing the old clay pipelines is a challenge. The old pipe is one reason the city has budgeted a million dollars annually for inflow and infiltration work.

North Carolina lost most of its textile mills after the passage of the North American Free Trade Agreement in the 1990s, with much of the industry moving south of the border. Today, Mooresville has no mill. What it does have is a concentration of NASCAR racing teams and support organizations. This is a reflection of the region’s fascination with racing stock cars, including at nearby Charlotte Motor Speedway. Mooresville’s chamber of commerce nickname is Race City USA.

The racing business is a clean industry in terms of waste products that make their way into Mooresville’s wastewater system. “From a waste product standpoint, the NASCAR industry really doesn’t add a lot to the system,” Kraft says. In addition, the town’s industrial park has some advanced manufacturing facilities and food industry plants, neither of which is a large- scale wastewater contributor. Another significant — and clean — employer is Lowe’s Home Improvement. Mooresville serves as national headquarters for Lowe’s Cos.


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