Congested underground infrastructure played a role in the large water main break earlier this month that left thousands of Dayton-area customers without pressure or service and led to a boil advisory, city officials said.
After a large main ruptured, the water that gushed out caused erosion that led to another pipe’s failure, causing disruptions to more customers.
The city has decided to reconfigure and reroute the piping that failed to create space between the lines to reduce the likelihood that one break will lead to others, officials said.
“This is an example of lessons learned and how can we improve this situation with an investment so that we are lowering risk in the future, enhancing performance and increasing redundancy,” Dayton City Manager Shelley Dickstein said.
The Dayton Daily News Path Forward project digs into solutions to the biggest issues facing our community, including the safety and sustainability of our drinking water. In this story, we examine what caused a third major water service disruption in less than 18 months and what the city is doing about it.
The city’s water is distributed to some 400,000 people, including about 250,000 people in Montgomery County.
City leaders told the Dayton Daily News that its water system’s performance and reliability are strong and improving, which is evidenced by the overall declining rate of water line breaks and leaks.
Also, the city recently issued a request for proposals to find a company to assess and repair its large water valves with the goal of improving its distribution system.
Aug. 3 incident
Dayton has not completed its review of the Aug. 3 water main break near the Ottawa Water Treatment Plant that flooded the streets and impacted about 27,000 customers mainly in downtown and eastern and southeastern Dayton, officials said.
City officials, however, say the break happened in an area where three separate water distribution pipes operated in close proximity to each other, though they were buried at different depths.
A 48-inch pipe installed in 1951 that serves the city’s low pressure area broke for still undetermined reasons, officials said. This break caused erosion that led to the failure of a 30-inch pipe installed in 1893 that serves the high-pressure system.
Severe erosion also damaged the surface of a 36-inch pipe, which was installed in 1926, that serves the high-pressure area, officials said.
The initial break impacted service to about 17,000 customers in the low pressure area. The second break affected about 10,000 customers in the high-pressure area.
After events like this large disruption, city staff and team leaders in the relevant departments perform a debrief to evaluate what transpired and how the city responded to the crisis, Dickstein said.
The city takes a close look at its performance, identifies areas for improvement and explores potential investments or projects that could prevent similar events in the future, Dickstein said.
Instead of just repairing the broken or damaged pipes, the city has decided to realign the 30-inch and the 48-inch lines to reduce the cluster of underground water infrastructure in the area, Dickstein said.
Pipes will be routed across Keowee Street at a location north of the break point.
The extra space, they said, should help prevent one water line break from causing additional line failures.
“If we are going to make this repair, let’s do it right,” said Michael Powell, Dayton’s director of the water department.
The city says it is evaluating whether other similar clusters of water pipes exist around the city.
The city also recently issued a request for proposals seeking a vendor to assess the condition of its large water valves and make repairs.
The water department has 21,517 system valves, and 667 are 16 inches or larger, which are considered transmission mains, according to city documents.
The city said large valves are critical to the “resilience” of its water distribution system and it wants a detailed report that spells out a rehabilitation plan, including the scope of the projects and cost estimates.
The vendor will complete repairs to valves the city’s water department deems “economically feasible” priorities, city documents state.
Officials said this request is unrelated to the recent break, but it will help prioritize capital improvement projects and improve the system.
Breaks and leaks
The city has about 100 water line breaks and leaks each year, though most are minor and have minimal impact on service, Powell said.
The Aug. 3 incident, however, was the third major water disruption since early 2019.
In February 2019, the city’s water distribution system suffered a massive and widespread outage after a large main in the river burst. Months later, the Memorial Day tornadoes knocked out power to parts of the city’s water system and led to another large water outage.
Each of the three major disruptions were different, and Powell said it is important to keep in mind that some things are out of the city’s control, like the record number of tornadoes that tore through the area on Memorial Day 2019.
The city also claims that a contractor working on a bridge replacement project was responsible for causing the first outage.
The city constantly evaluates its system, Powell said, and uses software and other tools to analyze data to figure out what repair and replacement projects are most urgent.
The goal is to evaluate the likelihood and consequences of infrastructure failures, he said, and special attention is given to critical infrastructure around schools, hospitals, police stations, recreation centers and other sites that are important during emergencies.
Main break history is one consideration in the prioritization process, and soil condition is another. The age of the pipes and the materials they are made of are other parts of the equation.
More than half (55%) of Dayton’s water pipes were constructed before the 1950s, and about 5% were constructed in the 1800s. Almost two-thirds of the pipes are cast iron, and rest are mostly made of ductile and concrete.
Powell said he’s not overly concerned about any type of piping in the 800-mile network that makes up the city’s system, despite the advanced age of some of the lines. He said most pipes were well made, have long life spans and remain in good shape.
Powell said Dayton’s water system has a much better performance record than other systems across the country.
The American Water Works Association’s target range for water distribution systems is 22.9 to 78.7 breaks per 100 miles of water piping, Powell said.
Last year, Dayton had 20.7 breaks per 100 miles of piping, according to city data. Between 2015 and 2018, the rate was between 22.4 to 60.4.
“We’re not just saying we have a well-run utility ― but according to AWWA benchmarks, they say we have an excellent-run utility,” Powell said.
Dayton officials said they cannot predict where breaks will happen, but that the declining rate of breaks and leaks shows their plan to upgrade the system is working. The plan dates back to 2012.
“There is a difference between proactive and clairvoyant,” said Joe Parlette, Dayton’s deputy city manager.
Dayton is investing about $30 million each year in new water distribution and sewer pipes, Dickstein said.
Between 2013 and 2019, the water department awarded 173 water, sanitary sewer and storm system projects valued at a combined $200 million, Dickstein said.
Also, Dayton is in a much better shape than other municipalities because its water, wastewater and storm water systems are separate, Dickstein said.
Dayton also is researching sensor-based technology that can help detect leaks early before they become breaks, officials said.
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