Thursday, December 19, 2024

Asheville’s Dirty Water Warns of Climate Risk to Aging US Infrastructure

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Hurricanes Helene and Milton devastated swaths of the southeastern US by bringing too much water. Now, communities are struggling with the opposite problem: too little of it.

The North Fork Water Treatment Plant supplies most of the drinking water to Asheville, North Carolina, and some surrounding mountain towns. Built in the 1970s, it was known for its clear water, which flows into the plant from a large reservoir.

Then Hurricane Helene barreled in late last month, dumping almost 14 inches of rain.

Engineers at the plant saw that water was rushing out of the facility at more than double the normal rate, which could only mean one thing: the 36-inch pipeline connecting the plant to Asheville’s network of 1,800 miles of pipes below must have ruptured. A backup line also was destroyed.

“Water from the plant was just blasting out, creating a 50-foot-deep crater,” said Brendan Kelley, the water plant supervisor on duty during the storm.

There was no choice but to shut the plant down, leaving almost no water for a system that serves 160,000 people. The city’s other big treatment plant, called William DeBruhl, was largely knocked out as well. Only a smaller plant remained operational.

Days later in Florida, Milton ripped through the state, knocking some water treatment plants offline for hours or days. Numerous boil-water notices are still in effect.

Read More: Hurricane Milton’s Floodwaters Are Hiding a Dirty Secret

The situation is worse in western North Carolina, where residents went weeks without water. Service in Asheville has largely been restored, but the water isn’t yet safe to drink and “there’s no accurate timeline” for when that will change, according to Clay Chandler, public information officer of the city’s Water Resources Department. While “a significant amount of repairs have been made” at North Fork, more work is needed to improve the water quality, Chandler said. The William DeBruhl plant is still offline and requires more repairs, he added.

The city’s woes illustrate how the age of the nation’s water infrastructure, combined with the increasing pressures of climate change, can push systems to collapse. That means what has happened in Asheville, absent mitigation efforts, is likely to play out in slightly different ways in communities across the country.

“The City of Asheville water system infrastructure is plagued with problems, and climate change has definitely found weaknesses in the system,” said John Shaw, a consulting civil engineer and former Asheville resident who still owns a home there. “It will probably take months for the city to get back up to speed, if not longer, because they have a lot of facilities to reconstruct,” he said.

Climate change can affect water systems in multiple ways. Increased temperatures and drought “have actual effects on the water supply itself,” said Zia Lyle, a PhD candidate at Carnegie Mellon University. The five-year drought that caused Cape Town’s water crisis, California’s long drought, and the 2023 drought in Sicily are all examples of how climate change can constrain water supply, simply by reducing the amount of rainfall. Cape Town’s drought was made three times more likely because of climate change.

Climate disasters can also impact water quality far downstream from where they took place. “I realize this is a cataclysmic event in terms of Asheville,” Hans Paerl, a professor of environmental sciences and engineering at the University of North Carolina Institute of Marine Sciences in coastal Morehead City, said of Helene. But all that water, and whatever is mixed in it, has to go somewhere: “It ends up down in my backyard on the coast.”

Because many urban areas don’t have enough absorbent vegetative buffers between impervious surfaces, the dirty runoff becomes a bigger issue, increasing the chances of fish die-offs, algal blooms and other environmental problems.

Other climate hazards, such as intense rainfall and wildfires, can affect the ability of utilities to maintain service in extreme circumstances. In 2022, for example, Jackson, Mississippi, residents lost reliable tap water after rains pushed the capital city’s already decrepit water treatment plant to failure.

In Asheville, Helene stirred up the reservoir so much that it looked like “chocolate milk,” Kelley said.

North Fork was designed for processing almost-pristine water. Water from the reservoir goes straight to filtration, akin to a giant Brita filter. But sediment will quickly destroy the filters, which could cause a bigger failure.

The plant doesn’t have a sedimentation-removal system. Adding one would cost about $100 million — a large chunk of Asheville’s $250 million annual budget. For now, the city plans to add aluminum sulfate and sodium hydroxide to the reservoir to cling to the sediment and get it to sink to the bottom, clearing up the water.

Even before Helene arrived, the city’s water systems were struggling from decades of delayed maintenance. In 2022, for example, the city experienced widespread outages due to the combination of a cold snap, aging infrastructure and higher-than-expected demand. It took nearly two weeks until service was fully restored.

Read More: American Dams Weren’t Built for Today’s Climate-Charged Rain and Floods

The US Environmental Protection Agency estimates it would take $625 billion over the next 20 years to get the nation’s public water systems up to snuff, up from roughly $300 billion in 1995 (both in 2021 dollars); the bulk of the funds would go to water distribution.

But the assessment is based on surveying public water systems and is heavily focused on immediate needs — such as replacing water distribution lines that contain lead. Future needs, such as those triggered by climate change, do not appear explicitly in the assessment, and there’s reason to think that the EPA’s estimate is an undercount.

In her research Lyle found that many water utility managers do not have climate adaptation plans. Such plans not only detail the risks their systems are likely to face in a warmer world but what steps they can take proactively to adapt to them.

This lack of forward thinking can be traced to a number of factors, including the fact that the federal government doesn’t require utilities to have such plans. But it also reflects that water utilities “really ground their risk perceptions in historical exposure,” said Lyle. “So if a system has encountered floods in the past, they may still understand that that could be a risk, and maybe that’s going to become a bit more exacerbated. But if a system had never encountered something like a wildfire or never encountered flooding for instance, they may not understand that in the future, they could be exposed to that risk. And so there’s a gap there in the resilience planning.”

There’s also a growing worker shortage.

The EPA survey found that roughly 35% of small water systems, and 50% of medium and large ones, had difficulty hiring employees or obtaining contracted workers, a phenomenon that is likely to grow worse as the water workforce retires.

“It isn’t like you just throw money at the problem and that’s it,” says Joseph Kane, a fellow at the Brookings Institution who co-authored a report on the aging water workforce. “You actually do need to have human talent to construct, operate and maintain these systems. And for a very, very long time the workforce sort of component of all of this was an afterthought.” By Kane’s estimate, some 30% to 50% of the water workforce is retiring in the next decade.

Plus, the work requires significant on-the-job training, says James Fahey, superintendent of operations at the environmental solutions company Veolia North America.

There’s a lengthy licensing process, but, said Fahey, “the real lesson is the experience working here. Working the days, nights, you know, going through the emergencies.” Emergencies such as power outages, wildfires and floods.

When asked how Asheville could have better prepared for Helene-like flooding, Chandler, of the city’s Water Resources Department, said: “I’m not sure that you could fully armor a water system against what we just went through.”

Photo: Volunteers distribute cases of bottled water during a water shortage in Jackson, Mississippi, Sept. 1, 2022. Photographer: Houston Cofield/Bloomberg

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