Streets, backyards and basements throughout Brookfield, North Riverside and Riverside took on water June 26 when a strong storm dumped more than three inches of rain onto the area in the span of just over an hour.
That rainfall followed in the wake of about an inch the day before, taxing local sewer systems, including the Metropolitan Water Reclamation District’s Deep Tunnel system. On Saturday before the worst of the rain came, the MWRD issued an Overflow Action Day alert on its Twitter feed, asking citizens to refrain from washing dishes, doing laundry and taking showers because of the strain already on the system.
Riverside Public Works Director Dan Tabb said that National Weather Service data indicated 3.25 inches of rain fell between 10 and 11:15 a.m. on June 26, while Brookfield resident Allen Goodcase’s weather station at his home on the village’s south end recorded about 3.5 inches on Saturday.
“I’m not sure any system can handle that,” Tabb said.
Residents of all three villages took to social media in the wake of the street and basement flooding that followed, decrying the ability of sewer systems to handle the storm water.
But, the flooding was not isolated to any one municipality. Similar basement and street flooding was reported throughout the suburbs and in the city of Chicago, where some streets became impassable, including First Avenue, which was closed to traffic between 31st Street and Ogden Avenue from about 12:30 to 6 p.m. after storm water flooded the area around the BNSF railroad bridge.
One vehicle, which had tried to make it through the high water, had to be towed from under the bridge. Unlike previous flood events, the viaduct was flooded by river water.
“The sewer system couldn’t take that amount of water out quickly enough,” Tabb said.
Brookfield and North Riverside both experienced sporadic street flooding as sections of the combined sewer system – meaning the pipes collect both sanitary waste and storm runoff – quickly reached capacity, backing up into streets and basements without some sort of flood-prevention system.
Even in areas of Brookfield and Riverside that have separate storm sewers, there’s no way to guarantee they won’t completely fill up during heavy storms, said Brookfield Village Engineer Derek Treichel.
“There’s always a limited capacity for the storm sewers,” Treichel said. “Even if you replace them all, you still have the issue of getting it into [Salt Creek] when it’s high.”
That’s because if the level of Salt Creek, or the Des Plaines River for that matter, rise above the level of storm sewer outfalls, the water can’t exit the system.
That’s why Brookfield a few years ago installed a pump station at the corner of Washington and Forest avenues, a particularly flood-prone area. On Saturday, said Brookfield Public Works Director Carl Muell, all five of the station’s pumps were activated, keeping Forest Avenue and the low-lying Washington/Prairie intersection dry.
“The pump station worked phenomenally,” Muell said.
Among those buildings taking on water in the basement was the Brookfield Village Hall, 8820 Brookfield Ave. According to Village Manager Timothy Wiberg, about two inches of water covered the entire lower level of the building.
Officials suspect the flooding resulted from a drain backup on the flat roof of the building. That blockage was cleared, but the basement flooded, forcing the Brookfield Parks and Recreation Department to relocate its summer camp programs to S.E. Gross Middle School and Riverside-Brookfield High School.
The lower level of the village hall will be closed to the public for about two weeks, Wiberg said, as officials determine the source of the flooding and fix it.