Aging infrastructure in a fast-growing city: Inside Charlotte Water after main breaks

If you were to line up all of Charlotte’s water and wastewater pipes, they would stretch from the Queen City to the Philippines, with room to spare.

Charlotte Water, the city utility that pumps an average of 109.7 million gallons of water a day, is made up of more than 8,900 miles of pipes. It’s something residents use each day and likely don’t think about — until there’s a big problem.

That happened on Monday afternoon when, in spectacular fashion, a water main break shot water into the air and above some treetops along the 1400 block of Remount Road.

Water service was disrupted. Boil advisories were issued. The cause remains under investigation.

But is this something that could happen again? How does the city’s growth play into infrastructure like water distribution? And how old is our infrastructure system anyway?

Water main breaks and leaks are not unusual, civil engineer and environmental experts told the Observer. But the incident on Monday, described by the Charlotte Water director as “historical,” highlights the need for keeping water infrastructure maintained and upgraded, the experts said.

“It really does come down to the aging nature of our infrastructure,” said Emily Berglund, a professor in civil construction and environmental engineering at NC State University. “As a civil engineer it’s kind of impossible not to beat the drum that (infrastructure) is underfunded.”

That’s why a roughly $1 trillion proposal from President Joe Biden to improve the nation’s roads, bridges, pipes, ports and Internet connections is so important, Berglund said. The bill passed the Senate in August and has been the subject of much debate around Washington.

But while age can be a factor in water main breaks, there are a number of other issues that might have contributed too.

How Charlotte Water’s system works

Charlotte Water’s history dates to the late 1800s when the city built a sewer service under Trade Street. By 1905, the city had its first water treatment plant built, and later added a 60-million gallon reservoir.

Today, Charlotte Water has two pump stations that take water from Lake Norman and Mountain Island Lake. Water is pumped to three treatment plants, Lee S. Dukes, Franklin and Vest.

The water is cleaned through several processes and then some of it is moved to a nearby water tower for storage and, later, distribution, Charlotte Water spokesperson Cam Coley said in an email. Water towers also help pressurize the distribution system. Water then travels through miles and miles of pipe to reach homes and businesses.

In the case of a water main break, the city’s plants push out more water to try to compensate for the breach.

How big is Charlotte Water?

Charlotte Water says it is the largest public water and wastewater utility in the Carolinas, serving 1.1 million customers in Charlotte and greater Mecklenburg County, including Matthews, Mint Hill, Pineville, Huntersville, Davidson, and Cornelius.

It has been in operation since 1889.

Charlotte Water is authorized to have over 1,000 workers, and has an operating budget, including debt service, of $502 million.

Older lines in Charlotte Water

In Charlotte, 6% of the overall system of water and wastewater pipes is at least 50 years old, including the one with the break on Remount Road, according to Coley. The highest percentage of pipes, about 66%, were installed between 1990 and 2000.

The pipe that had the break was 36 inches in diameter, made of pre-stressed concrete cylinder and buried 15 feet under a creek bed. It was installed in 1955, Angela Charles, director of Charlotte Water, told reporters Tuesday.

Charlotte Water is not sure if age was a factor in the break but it can play a role in a water main break like the one seen on Monday, Charles said during a news conference.

The city has some old cast iron pipes from the 1920s and ‘30s that she said are “performing quite well” due to their thickness. The type of pipe in the ground will impact how long it can last, Charles added.

Cities around the US

Other cities also are dealing with older lines as well.

In Fort Worth, Texas, a city of comparable size to Charlotte, about 19% of city-owned water mains are over 50 years old, water utility spokeswoman Mary Gugliuzza said. In Columbus, Ohio, another city that’s similarly-sized to Charlotte, about 42% of the entire water system is at least 50 years old, according to a spokeswoman for Columbus Department of Public Utilities.

Cities like Columbus also say they look at type of material versus age when gauging performance of the system.

How well and how long a water pipe lasts underground is not based on age but rather material used across different eras.

“An older cast iron waterline that was a hundred years old can last longer than different materials from 50 years ago,” Laura Young Mohr, a spokeswoman for Columbus Department of Public Utilities, said in an email. “We base our capital improvement program replacement needs on break history, not age.”

Then there’s Philly.

In July, a water main in Philadelphia that dated to 1891 broke and sent water gushing out onto city streets. About 15% of the city’s water mains were laid out before 1900, according to the local CBS TV affiliate.

A need for customized plans

NC State’s Berglund said that, in general, a 30- to 50-year life cycle is good guidance on when to replace pipes. But replacement could be based on other factors, like what materials were used and soil conditions.

The industry has tried to move away from a rule of thumb to replace a pipe after a certain amount of years, said Shadi Eskaf, director of the water division for the North Carolina Department of Environmental Quality.

It depends on the soil conditions — some soil can be more acidic and lead to corrosion. Or conditions can shift from wet to dry, for example.

A pipe’s life cycle can also depend on how much pressure moves through it over time or new projects coming online like light rail lines or road widenings.

The better practice, Eskaf said, is for each city to customize its plan around an assessment of its water infrastructure. Find out which pipes are in poor condition and need to be rehabbed or replaced. States help provide local governments with grants on coming up with that type of plan, he said.

Balancing growth with maintenance

Nothing can happen in a community without water or sewer, said Charles, the Charlotte Water director. And in a city that’s been growing as quickly as Charlotte, the utility has a primary goal of meeting the needs of people and planning for future growth.

Charles said there’s a constant internal tug in her agency between meeting those growing needs and rehabilitating and replacing a system that dates to the 19th century.

“I want to see us do more rehab of what we have,” Charles said. “If you build and develop, you can’t do it if people can’t wash, brush or flush.”