COLUMBIA, Mo. (KMIZ)
After a water main break near the University of Missouri's campus last month flooded a parking lot and the basement of a residence hall, ABC 17 submitted a records request to learn how many water main breaks have happened in the city.
Since Jan. 1, 2020, through October of this year, the city has had 534 water main breaks.
Data from the City of Columbia shows that water main breaks are not limited to just one part of the city. This map breaks down the locations of all of the city's water main breaks since Jan. 1, 2021, with each color representing a different year.
There have been 142 water main breaks in the city through Oct. 24 of this year, with the majority coming from unknown causes, followed by deterioration.
There has been a steady rise since 2020, with main breaks more than doubling from 2020 to 2021. There were 72 main breaks in 2020, 146 in 2021, and 174 in 2022.
Columbia Water and Light Engineering Supervisor Shawn Carrico said the main factor behind water main breaks is a change in weather and soil conditions.
"In our area, we typically have clay-type soils and they will move, expand and contract a lot depending on how moist the soil conditions are," Carrico said.
Seasonally, 41% of the breaks happen in the summer, followed by 26% in the fall, 19% in the winter and 14% in the spring.
Carrico said this is because summer is when the ground is most dry, and fall is when the first freeze occurs and the soil becomes more moist.
Records show 37% of the breaks are from unknown causes. 24% of the breaks come from deterioration and 17% from differential settlement--when pipelines travel through varying soil conditions.
Carrico said most of the breaks occur in cast iron pipes, which were installed starting in the 1950s to the early 1970s. He said water mains typically have a 100-year lifespan, and as the cast iron pipes get older, the city's budget for main replacements will increase.
"We try to get as much life as possible out of it," Carrico said. "Obviously, the more aggressive we are in replacing, the larger our budget is, which equates into higher rates, so there's a delicate balance to the whole approach."
He said 27% of the current pipes are still cast iron, while about 60% are now PVC pipe.
He said the city is on par with the national average for water main breaks, and does not directly track the cost of main repairs or replacements.