When a 36-hour cooking advice wreaked havoc in Wichita on October 7th and 8th, Alan King, the city‘s site manager, wanted to make one thing clear.
“It was a failure of the distribution system,” he said.
The entire water treatment plant is in poor or very poor condition, a 2017 study found. The same study found that 46% of the city’s water supply lines are in poor or very poor condition.
A second water treatment plant – a $ 494.2 million project being built along 21st Street and Hoover Road – is slated to go online in 2024. But what is the city doing to prevent more pipes from bursting?
“We have a significant budget to replace tubes,” said King. “We jacked it up significantly.”
Here’s a breakdown of the condition of the pipes that carry Wichita’s drinking water, the system the city uses to repair and replace them – and how one slipped through the cracks.
The state of Wichita‘s water supply system
King said the condition of Wichita’s water distribution pipes was “uncommon for any water system in the United States.”
Joshua Roundy, Associate Professor of Civil, Environmental, and Architectural Engineering at the University of Kansas agreed. He referred to an annual report by the American Society of Civil Engineers (ASCE). The Report Card for America’s Infrastructure gave the national drinking water infrastructure a C-Minus in 2021 and a D in 2020.
“Our water infrastructure has been underfunded for a long time,” said Roundy.
In Wichita, about a third of the water pipes are over 50 years old. Less than a tenth of 1 percent are over 100 years old. The oldest is from 1910.
“We’re a pretty new system,” said Kara McCluskey, Associated Engineering lecturer who teaches courses on water distribution systems at Wichita State University. “I know this seems pretty old, but some of the older cities still have older pipes.”
Water pipes can last up to 150 years depending on the material and environmental conditions, said Celine Hyer, member of the ASCE Committee on America’s Infrastructure and author of a chapter on drinking water in the infrastructure report. However, Roundy found that problems typically arise when pipes are around 100 years old.
King said water pipes in Wichita are made of a variety of materials, including cast iron, concrete, and plastic.
In the past six years, Wichita’s water supply system met a nationally recognized American Water Works Association (AWWA) standard for pipeline leaks and breaks half the time.
Wichita‘s pipe replacement program
According to King, the city spends between $ 10 million and $ 11 million a year on water pipe replacements – a much higher figure than when he arrived in 2011.
“As soon as the council became aware of how we were against [the AWWA] Benchmarks and the rest of the country they adjusted the replacement, ”King said.
The pipe replacement program consists of two steps. First, the city is doing an inventory of its 2,400 mile long aqueducts, using age, material, and fault history data to provide an approximate risk score for each line. The city last did this in 2017, King said. According to ASCE’s Hyer, best practice is an annual assessment.
Next up is an on-site review of factors such as pipe erosion and joints. The city usually decides which pipes to run for this step based on the number and frequency of breaks in a line.
“When we dig up a pipe to fix it, we go to see the condition of the pipe,” said King.
The city typically weighs the cost of further repairing a pipeline against the cost of replacing it in full.
King pointed out that small pipelines that carry water through neighborhoods are being replaced more often than large pipelines that usually carry water from the sewage treatment plant to areas with high water consumption.
This is largely because of how few breaks experience large pipes – only six, according to King, since 1996. The break that caused the boil warning earlier this month was one of them.
When large pipes break, King says, the city usually finds that the problem is around the area of the break, rather than in the pipe itself.
How did you turn the whole system upside down?
“If it hadn’t been where it was in the system, you wouldn’t even have known about (the burst pipe),” King said.
Although the city is still testing the failed line, King said one theory is that road salt runoff from the freeway was corroding the line.
King said the city does not track soil corrosivity throughout its aqueduct system. But the city can test the soil in locations with conditions similar to those around the broken pipe to update its modeling of the water system.
The most important change the city will make in the future is to have its own diesel generators supplied to the water system during storms in order to avoid breakdowns. King believes that a fault in the electrical network triggered the initial change in pressure that led to the major rupture.
What standards does Wichita live up to when it comes to keeping the water supply system up to date?
Basically nobody.
The Kansas Department of Health and Environment does not regulate the replacement or repair of water pipes. While some states have “asset management” requirements that require water utilities to create plans for pipe replacement and inspection, neither the federal government nor Kansas do, Hyer said.
The Wichita water company must submit a water master plan to the KDHE and is reviewed by the authority every three years. These inspections “focus on visible infrastructure, operation and maintenance records and water quality reports,” wrote KDHE spokesman Matthew Lara in an email.
King stated that KDHE “is a results-oriented organization” and that “we have an obligation to achieve certain results – water quality, things like that. How the individual water supplier does it is up to them. “
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