Two summers in a row, large rain storms have caused widespread flooding in East Lansing. Now, an independent review of last year’s biggest flooding incident presented at the Tuesday, Sept. 13, discussion-only city council meeting makes it clear future floods are possible. Even likely.
The review of the flooding that occurred because of the rains on Aug. 12, 2021, conducted by engineering firm Tetra Tech, revealed that the cause of the flooding was intense rainfall for an unusual duration of time, Tetra Tech Senior Water Resource Engineer Dan Christian told city council.
“On an individual, small increment, we’re doing Ok, but it’s because it didn’t let up,” Christian said. “It just kept raining and it kept raining hard, which is a little unusual in the rain patterns.”
Christian said East Lansing’s sewer system is built to withstand up to a 10-year storm, or storms that have a 10 percent chance of happening in any given year. Using available data from reliable sources, Christain concluded the 2021 storm was about a 140-year storm.
The concern now is that the scale dictating how often storms should happen is out of date, as climate change has made severe weather events more common.
The extreme weather events can cause the city’s sewage system to run at the limit of capacity, Christian explained. When this happens, excess rain water stays on the streets because there is nowhere for it to drain. This can lead to street flooding and flooding in basements or crawl spaces due to water backing up through floor drains or water leaking in through cracks.
Calling in to join the conversation by phone due to illness, Acting Director of Public Works Nicole McPherson said that the city is working on projects that will help reduce the harm of severe rain storms going forward.
However, some storms are simply going to be too big for the sewer system to handle.
“Our sewers, even designed at a 10-year or above design standard, are never going to, I hate to say ‘never,’ [but] are not designed to take on those 100-year storm events,” McPherson said.
Christian said Tetra Tech had talked to five Glencairn neighborhood residents whose homes had flooded and they all reported the water was clear and odorless. However, council member Lisa Babcock said she talked to several residents who had water containing fecal matter come up through floor drains.
The flooding isn’t happening solely in one part of the city. While the flooding has been more frequent in some areas like the Bailey and Glencairn neighborhoods, there have been incidents reported all over the city.
Homeowners in the Glencairn neighborhood hoped the big sewer reconstruction project would help their homes stay safe from flooding.
When John McNamara moved into his Glencairn home near the corner of Northlawn Avenue and Evergreen Avenue in 2020, he was told it was built in 1940 and showed no history of flooding. But following the Saturday, Sept. 3, 2022, storm, he reported to ELi the home has now flooded in two consecutive years, even after the sewer reconstruction’s completion.
McNamara said he filed an insurance claim for about $12,000 after the first flood and considered the incident an Act of God. Now that it has happened two years in a row, he’s wondering if redoing his basement is even worth the trouble.
“[The flood] rendered two rooms in my house I use frequently somewhat unusable until this is a fixed solution,” he said, adding he will have to disclose the history of flooding if he decides to sell the house.
McNamara said he learned some ways to minimize the damage after the first flood, like using a shopvac to remove standing water, running dehumidifiers and ripping up flooring. Still, flooding from a floor drain spread dirt and standing water through a hallway and multiple basement rooms in McNamara’s home.
Nearby Glencairn resident Paul Troutman also experienced flooding after the Sept. 3 storm. He said he walked down to his basement after the storm to find standing water. He manually pushed that water to a drain in the middle of a room sloped toward the center. After moving the water, there were two or three inches of standing water on top of the drain.
Troutman had a plumber do a sewer line scope after the flooding. That showed there were no blockages that would cause his home to flood. The incident has made him lose trust in East Lansing’s utilities.
Troutman, who has a background in civil engineering and just moved into his home a few months ago, is left uncertain about what he can do to prevent future floods.
“Neighbors are saying that they have mitigation systems, they have backflow preventers, they have sump pumps and they still had this happen to them,” he said. “That, to me, makes me think, ‘OK, this is going to happen again. So, I can’t do anything in my basement, I can’t put anything of value down there.’”
Council members asked what else can be done to address the problems.
At this week’s public discussion on the matter, council member George Brookover was concerned about construction debris washing into catch basins and blocking them from absorbing water on the street. Christian said anytime the basins are blocked during heavy rainfall, it’s a concern.
Brookover said he’s gone outside during storms to clear catch basins near his office himself on several occasions. (His office is located at the corner of Northlawn Avenue and Abbot Road, in the area that was the subject of the independent review.)
“It is pretty funny to see me out in big rubber boots in the middle of a rainstorm with a rake, raking the debris out of the city catch basins,” Brookover said.
Christian said the issue could be that the pipes downstream from the basins don’t have the capacity to accept more water flow, or the basins themselves don’t have a big enough capacity.
Acting Deputy Director of Public Works Ron Lacasse told Council the city sends staff to areas with catch basins that are at risk of being blocked during storms and also sweep the streets more frequently than most cities to keep the amount of debris down.
Christian said that adding catch basins can be useful, but would not be helpful if the pipes downstream are at capacity. He also said some communities have used “Adopt a catch basin” programs where community members commit to keeping drains near them clear of debris.
Council member Dana Watson asked if setting up rain barrels would be helpful. Christian said rain barrels are not big enough to prevent flooding during large rain storms like the ones that have caused flooding.
Babcock said the city needed to find a solution and proposed using more money from the American Rescue Plan to help fund the fix.
“Perhaps we need to change our priorities, our perspectives,” she said. “It’s just unreasonable for people to have to live with fecal material coming into their homes.”
City Manager George Lahanas said the city was planning to have another study done to determine actions that could be taken to increase the capacity of rainwater the city can absorb.