Illinois Issues: Urban Flooding

Sep 10, 2015

Heavier rainfalls and sprawling development have left outdated sewers struggling to keep water out of streets, businesses and homes. 

Big rainstorms are hitting Illinois more often. In many cities and towns, the sewers can’t always handle heavy downpours. Without anywhere to go, the water fills streets, yards and basements.

The result? At least $2.3 billion in damage from 2007 to 2014. That’s the total that the Illinois Department of Natural Resources calculated in a report this summer, tallying up insurance payouts for flooding damage in the state’s urban areas.

And the report warned that the problem could get worse.

One reason for the increase in flooding is climate change. Average temperatures in Illinois have warmed by about 1 degree over the last century. And warmer air can hold more water vapor. That could explain why precipitation in Illinois has increased 10 percent over the past 100 years — from an average of 36 inches a year to 40. Over the past decade, Illinois cities experienced an average of 1.8 storms with 4 or more inches of rain — the highest that rate has ever been.

“There’s definitely a trend toward increasing amount of storms and increasing intensity,” says one of the report’s authors, Brad Winters, an engineer with the Department of Natural Resources’ Office of Water Resources.

Many cities built their drainage systems to handle storms of a certain size. One standard they use is often called “the 100-year storm” — a large downpour with a 1 percent chance of happening in any given year. But the numbers being used to calculate the size of a 100-year storm are obsolete, Winters says.

For example, a National Weather Service report from 1961 predicted that a storm with 5.75 inches falling within 24 hours was likely to happen once every 100 years around Chicago’s O’Hare International Airport. Many local officials used that document to calculate how big to make their sewer systems. But new reports came out in 1989 and 2006, increasing the size of the 100-year storm to more than 7 inches. And even those numbers are too small now. 

flooding insurance claims in urban areas by county
Credit Clayton Ballerine / Illinois State Water Survey​ (ISWS), 2015

“We should be recalculating the percentages — because they’re changing,” says Hal Sprague, water policy manager for the Center for Neighborhood Technology, a Chicago-based nonprofit that promotes sustainable urban communities.

The Federal Emergency Management Agency uses predictions for a 100-year storm when it maps out areas with the highest risk of flooding — known as the floodplain. But in Illinois, more than 90 percent of urban flooding damage insurance payouts are for properties outside FEMA’s floodplain, according to the state report.

“That was startling,” Sprague says. “Somebody’s missing something here.” Why is so much flooding happening outside FEMA’s floodplain? Sprague suggested it’s because FEMA focuses on one type of flooding — water flowing across the land — while much of the damage is actually caused by water backing up from overloaded sewers into basements.

“We’re interested in having FEMA look into this,” Sprague says. Two Democratic members of Congress from Illinois — Rep. Mike Quigley of Chicago and Sen. Dick Durbin — have introduced bills calling for FEMA to do a study similar to the Illinois report on urban flooding. “Similar data would be developed for major urban areas around the country,” says Sprague, whose group supports Quigley and Durbin’s bills. So far during this session, no Republicans have signed on as co-sponsors of the Urban Flooding Awareness Act.

Environmentalists like Sprague hope a more accurate map would lead to more restrictions on what’s built in areas prone to flooding. “We need to strengthen our local building codes to prevent people from building where the risk is too high,” he says.

That points to another reason why flooding has grown worse in Illinois: because people keep building. And that leaves less open ground to soak up rain.

According to the National Land Cover Database, Illinois had 3,238 square miles of developed land within its urban areas in 2011 — compared with 1,815 square miles in 1992. That’s an increase of 79.8 percent, or 1,423 square miles, over 19 years.

Here’s one example of how development affects the flow of water: Flooding in Rockford tends to happen in areas where more of the ground is covered with pavement, says Timothy Hanson, the city’s public works director. “You can just watch the creeks rise, because it’s all coming off all the streets and all the asphalt surfaces over on the east side,” he says. “Along Keith Creek, that’s where you have all the big box stores. … And that usually is the creek that floods.”

The Illinois Department of Natural Resources is writing a model stormwater ordinance for local municipalities — including recommendations on zoning and development. “It’s voluntary,” Winters says. “We’re just saying: ‘You can always be more stringent, but this is a really good place to start.’”

Flooding in the Chicago suburb of Midlothian
Credit Center for Neighborhood Technology

  It isn’t always obvious to homebuyers that they’re purchasing a house in a spot that’s likely to flood. “I had absolutely no idea,” says Joel Kurzman, recalling when he moved to north suburban Wilmette 10 years ago. “My property was lower than other properties, but we’re talking very modest grades. A first-time homebuyer walking down the street would have no idea. But when the sewer system doesn’t take water, water finds its way to the lowest place. That’s what happened to our cul-de-sac. Our cul-de-sac was a lake. Vehicles couldn’t get in or out.”

Kurzman, whose home was not in the FEMA floodplain, says he avoided major damage by spending $10,000 to install an overhead sewer. But during floods, water surrounded his house. He founded a group called Dry Out West Wilmette, which lobbied the village to do something about the problem, and Wilmette ended up putting a 5.5 million-gallon sewage detention tank in the area, with a budget of $15 million.

Kurzman sees lax zoning as one cause of flooding. “Municipalities are their own worst enemy,” he says, criticizing suburbs for allowing construction on “every little parcel.”

One way of reducing floods is to build bigger pipes and tunnels to carry away that water when it comes pouring down. The Metropolitan Water Reclamation District of Greater Chicago has been working for decades on a massive $3.8 billion project to do just that.

In 1975, it began building the Deep Tunnel, with 109 miles of rock tunnels that can hold 2.3 billion gallons, as deep as 300 feet underground. The tunnel was finished in 2006, but the overall Tunnel and Reservoir Plan is scheduled to take another 14 years to complete. It also includes the Majewski Reservoir, which opened in 1998 with a capacity of 350 million gallons near O’Hare. The newly completed Thornton Reservoir opened September 1, providing 7.9 billion gallons of storage at the site of a limestone quarry in the south suburbs. And excavators in the west suburbs are still working on the 10 billion-gallon McCook Reservoir, where one section is scheduled to open in 2017, followed by the final section in 2029. 

We can't get the water from one place to another fast enough when it rains hard.

“It will just have a huge impact,” says David St. Pierre, executive director of the Metropolitan Water Reclamation District.

One reason officials decided to do all this digging was that Cook County has a combined sewer system, with sanitary sewage and stormwater flowing into the same pipes. When there’s too much water for the district’s treatment plants to handle, combined sewers overflow into local rivers. These overflows used to happen about 100 times a year. The Deep Tunnel project — funded by a mix of federal and local money — hasn’t eliminated that problem, but overflows happen less often, about 50 times a year.

The partially treated wastewater pouring into the Chicago River poses health risks for people who come into contact with it, like the growing number of people in kayaks and boats. The Metropolitan Water Reclamation District’s testing “reveals high levels of bacteria from human waste at more than a dozen spots stretching through the North Side and downtown to the Bridgeport neighborhood,” the Chicago Tribune reported August 28. Germ levels routinely exceed state standards for recreational waterways, but those numbers are expected to drop next year as the district begins using disinfection equipment.

St. Pierre says the new Thornton Reservoir is so big it could have held all the rain that came down during one especially intense deluge on September 13, 2008, when 6.64 inches of rain fell. That was an all-time high for rainfall in Chicago, until another storm broke the record on July 22-23, 2011, with 6.91 inches.

Having the capacity to hold all that water doesn’t mean it would flow through sewers and tunnels fast enough to prevent all flooding everywhere. “If you get 5 inches of rain on your house in an hour and a half, it really doesn’t matter what’s going on on the other side of town. You’ve got a lot of water,” says Winters, of the Illinois Department of Natural Resources.

And many parts of Cook County are miles away from the Deep Tunnel and its reservoirs. “If it rains harder farther away from the big trunk, then it’s probably going to flood there, no matter what,” says Sprague from the Center for Neighborhood Technology. “We can’t get the water from one place to another fast enough when it rains hard.”

But St. Pierre says, “At least it has somewhere to go. If it doesn’t have anywhere to go, then you have that lasting devastation across the region. This will tremendously help.”

Federal authorities pushed for the Metropolitan Water Reclamation District to finish its Tunnel and Reservoir Plan, resulting in a 2014 consent decree. That decree also requires the district to develop green infrastructure — such as distributing free rain barrels.

“The rain barrel program is going a little too well,” St. Pierre says. “The consent decree says we have to distribute 15,000 in five years. We’ve distributed 11,000 already.” The district plans to order another 60,000 soon, he says.

In another green initiative, the district worked with Chicago Public Schools last year to convert paved areas at four elementary schools into turf fields, gardens and landscape features that absorb water. “All these schools were just 100 percent asphalt,” St. Pierre says.

“The real solution … is to make sure that we take green infrastructure really seriously,” says Jessica Dexter, staff attorney with the Chicago-based Environmental Law & Policy Center. “Because there’s no way we can build enough pipes to manage the problem.”

The Water Reclamation District passed a watershed management ordinance in 2014, regulating water drainage and detention at new developments in Cook County. Dexter’s group pushed for that ordinance to require green infrastructure. “What we have is actually pretty good in that ordinance,” she says. But she added, “In a place that’s already built out like Cook County, there just aren’t going to be that many projects that trigger it fast enough to build out the green infrastructure the way we need to.”

A Chicago alley fitted with permeable pavers as part of the city's Green Alley initiative
Credit Center for Neighborhood Technology

Green infrastructure is also a talking point for the Illinois Department of Natural Resources, which encourages rain gardens, permeable pavement and green roofs, which are covered in plants meant to help soak up precipitation. “It can reduce the amount of water that makes it into the system,” Winters says.

Chicago officials have often touted the city’s green efforts. More than 350 buildings in the city have green roofs, totaling over 5.5 million square feet, according to an April 2014 report from the city. Chicago has also installed more than 330,000 square feet of permeable pavement in 200 alleys. Overall, the city says it has reduced 3 million square feet of impervious surfaces since 2008.

The real solution is to make sure that we take green infrastructure really seriously. Because there's no way we can build enough pipes to manage the problem.

  Another example of green infrastructure is popping up in the south suburb of Blue Island, which began planting rain gardens at five street corners in mid-August. “That’s pretty exciting,” says Danielle Gallet, a program manager at the Metropolitan Planning Council. That nonprofit coordinates the Calumet Stormwater Collaborative, bringing together Blue Island with two dozen other governments and agencies to seek solutions for flooding along the Calumet River, which runs through Chicago’s South Side and nearby suburbs.

For property owners, one of the most confusing things about all of this can be flood insurance. National Flood Insurance Program policies cover damage when water floods over land into a building. Private insurance companies offer riders on their policies to cover damage from sewers backing up into basements. But none of these policies cover the damage when water seeps in through cracks in walls or foundations, because that’s considered the building owner’s fault for failing to do upkeep.

The National Flood Insurance Program subsidizes insurance policies rather than making property owners pay the full cost, but Judy Biggert led efforts to change that. In 2012, when the Hinsdale Republican was serving in the U.S. House, she pushed legislation to phase out those subsidies, arguing they encouraged people to build in flood-prone areas while taxpayers footed the bill. The Biggert-Waters Flood Insurance Reform Act became law, but people across the country complained when their insurance bills shot up.

In 2014, Congress changed the law again, limiting individuals’ premium increases to 18 percent a year. “It kind of slid back, with this new flooding bill,” says Biggert, who left Congress after losing the 2012 election. “What we wanted to do was reduce the cost of the federal program.”

One way of getting buildings out of high-risk areas is for governments to buy them. FEMA and the state offer municipalities financial help to do this. “We had two major floods in 2006 and 2007. It flooded them out and just ruined everybody’s houses,” Hanson, the Rockford official, says about one neighborhood with 130 homes. “So we bought everybody out. And we took out the houses.” The Water Reclamation District recently helped buy homes in north suburban Glenview and another area near the Des Plaines River. “These houses are inundated,” St. Pierre says. “There really is no solution. There’s nowhere to move that water. It will go there every time.”

Meanwhile, some cities are turning to new forms of technology to get a handle on flooding. Decatur uses real-time monitoring devices on the underside of manhole sewer covers, which send alerts when a sewer is about to overflow. And Rockford bought a drone for $1,000 to get aerial views of flooded areas and obstructions in its creeks.

Winters acknowledged that the state’s budget problems could hamper its ability to fight flooding, but he says sources of money are available from various federal and state agencies to help local officials. And at least 25 municipalities in Illinois have stormwater utility fees to cover the costs of anti-flooding projects. “The best model is the one where they charge people based on the amount of impervious surface they have,” Sprague says.

The U.S. Environmental Protection Agency’s State Revolving Fund channels money through the Illinois EPA for low-interest loans to local municipalities, businesses, homeowners and nonprofit groups for water quality projects. The Metropolitan Planning Council has been working with the IEPA to improve local access to these loans. “We want to make sure that that process is as streamlined and as transparent as possible, so that as many communities as possible are coming in for those funds,” says the council’s Gallet.

In the fiscal year ending September 30, 2014, Illinois received $63.3 million in federal grants, for a cumulative $1.75 billion in federal money in the Illinois loan fund. The state is required to provide 20 percent in matching funds. In 2014, Congress expanded the loans to cover stormwater projects, and Gallet suggested that the state could be doing more to use these loans for work that reduces urban flooding.

Credit Clayton Ballerine / Illinois State Water Survey​ (ISWS), 2015

  The recent state report recommended giving all counties authority over stormwater. Only 15 counties in Illinois currently have that authority, plus the Metropolitan Water Reclamation District, a separate taxing body that covers nearly all of Cook County. Winters says it just makes sense to look at flooding problems across a whole county. “One city upstream has an effect on the cities downstream,” he says. “That’s where the counties end up having an important role.”

State legislators granted more powers to the Metropolitan Water Reclamation District in 2014, including the ability to issue bonds for local stormwater projects. That enabled the district to work with the city of Chicago this year on a $55 million drainage tunnel in Albany Park, a neighborhood that’s been hard hit by flooding.

In February, Mayor Rahm Emanuel announced that $15 million in federal community development block grant funds would help pay for that project. The Chicago Sun-Times quoted Emanuel remarking that major rainstorms are likely to be a regular occurrence in the years ahead: “The new normal is the abnormal when it comes to weather patterns.”