St. Louis Park's water main breaks are 'canary in the coal mine' for aging suburban infrastructure

A year ago, dozens of St. Louis Park residents woke up to sludge spewing from basement drains and toilets as over a million gallons of water, dirt and sewage rushed into more than 50 homes, flooding basements with more than two feet of muck. Two weeks later, another water main break nearby flooded some of the same homes again.

The basements are dry and mostly repaired, but officials in St. Louis Park and other suburban cities are growing more concerned about their water mains and sewers coming of age all at once — and what it will cost to keep up with repairs. In Excelsior, residents are paying higher property taxes after a series of water main breaks in 2020. In Bloomington, they're seeing water and sewer rate hikes so the city can keep up with repairs.

"We may be the canary in the coal mine for first-tier suburban communities," St. Louis Park Mayor Jake Spano said.

The Twin Cities' inner-ring suburbs boomed in the years just after World War II, with many cities built in a single spurt of development. More than 60% of St. Louis Park's houses were built between the late 1940s and early 1950s, and nearly all the water and sewer infrastructure was in the ground by 1960.

The infrastructure worked well for decades. But as those water mains and sewer lines get older, cities are going to have to do more to monitor and maintain them — which will mean spending more.

"For a long time in newer communities, suburbs, the infrastructure was essentially brand new," said Scott Anderson, utilities superintendent in Bloomington. "A lot of that infrastructure is tending to age out all at once, or in big pieces."

Older, larger cities aren't immune. Duluth, which saw most of its water and sewer infrastructure installed in the 1930s and early 1940s as part of the Works Progress Administration, has been dealing with water main trouble in recent years.

The May 21, 2022, water main break in St. Louis Park was the result of soil around the cast-iron pipes corroding a series of holes in the main, which was installed under Minnetonka Boulevard in 1956. An investigation by an outside firm found water from the holes broke into a nearby sewer line, pushing 1.1 million gallons of muck into homes. Replacing the broken section of pipe put pressure on a nearby section of water main, which cracked in early June and sent more water rushing into basements.

Julie North's basement was one of those that flooded. A year later, repairs are almost done, and the rooms have been re-furnished with a couch, chair and TV stand from Facebook Marketplace and local Buy Nothing groups.

"We're happy we're getting back to a livable state," North said, though the garage is still jammed with stuff she fished out of the basement last year. She had retired in 2021, but said she went back to work teaching in part to help cover the repair bills.

Neighbor Linda Lovejoy is almost done fixing her basement too, but she can't replace 50 years' worth of photo albums she had stored there. The soaked albums are still in her garage, she said. "I don't know what to do with them!"

To help make repairs, the city authorized spending $4 million for resident relief, and has distributed more than $830,000 so far, Spano said. The relief program is set to end Aug. 1.

North and Lovejoy said they felt the city came through for homeowners, especially because many of their homeowners' insurance policies did not cover damage from water that flowed in from outside their homes.

Lovejoy said she's worried about other neighborhoods in St. Louis Park.

"Who's going to be next?" she asked. "We have old infrastructure!"

St. Louis Park has 160 miles of water main, almost all made from cast iron meant to last 100 years — similar to many other suburbs its age.

Some may last longer, but some may corrode earlier, and the city is trying to get ahead of possible damage. St. Louis Park is seeking money from the 2021 federal infrastructure bill to help repair more water infrastructure, Spano said, and has begun to incorporate water main maintenance and replacement as part of its regular street repair work. The city also has purchased a $400,000 machine that can scan the walls of water mains for weakness.

Spano said the water main breaks have hammered home the importance of road, water and sewer systems, the "drink-drive-flush" core functions of local government.

"If we don't get these core services right, none of the rest of it will matter," he said.

The cost of maintaining that infrastructure could influence the city's spending priorities going forward, Spano said. The city might work to cut costs in other areas, and raise revenue with either grants or increased property taxes in years to come.

Spano said seeing the damage from last spring has made infrastructure feel more urgent, and more personal.

"I hope this changes the discussion around priorities," he said. "When you have stood in someone's basement and seen baby blankets and photo albums soaking wet and piled on the ground, it changes your perspective."