The U.S. Army Corps of Engineers made its case for installing a battery of flood-control structures along the Des Plaines River in Riverside between Park Place and the BNSF Railroad bridge.
An overflow crowd of 40 to 50 residents jammed the council chamber inside the Riverside Township Hall, taking up positions behind (and, in the case of one senior citizen, in) the chairs of village trustees who fielded questions and concerns for two and a half hours.
While Army Corps Project Manager Jeff Zuercher’s presentation didn’t stray too far from plans the agency unveiled in 2013, some of the finer points to the proposed effort came into clearer focus, not all of them greeted warmly by the residents the changes would impact.
“I have real fear that my property value will absolutely be decreased,” said Mary Erangey regarding the prospect of a floodwall being built along the east riverbank behind the homes on West Avenue.
Erangey’s home is one of the few on the block not considered to be in a flood plain, but the wall, she said will remove what made the property so attractive in the first place – direct access to the Des Plaines River.
Zuercher said the project would mean homeowners would need to sell roughly 15 to 17 feet of property to create an easement that will protect the integrity of the floodwall.
“Part of the reason we bought there was because we have river access,” Erangey said. “I kayak. We will lose that and we will have a wall in our backyard.”
The presentation also revealed that the Army Corps of Engineers is now considering erecting a floodwall running east and west along Park Place, tying it into the Groveland levee, which itself will be raised two feet by driving steel sheet piling into the levee.
The sheet piling above the Groveland levee is proposed to be exposed, a detail that elicited groans from the audience. Zuercher said that because 65 percent of the roughly $7.1 million project is being funded by the federal government, the Army Corps’ mandate is to solve the problem at the least possible cost.
The additional cost for any aesthetic upgrades, such as covering the sheet piling, would have to be picked up the local sponsor, in this case, the Metropolitan Water Reclamation District.
Computer modeling presented by the Army Corps and vetted by the village’s engineering firm indicates that the floodwalls, increasing the height of the Groveland levee and installing some sort of floodgate at the east end of the Forest Avenue bridge will protect the Groveland/West/Park Place/Lincoln/Forest area from a 100-year flood.
The Army Corps estimated the crest of a 100-year flood as being more than two feet higher than the record Des Plaines River crest in Riverside, which occurred in 2013 and resulted in extensive flooding south of Park Place.
Asked by residents why the levee and new floodwalls had to be built to such a height when the Groveland levee itself has never been topped, Zuercher said that the plan conformed to mandated federal standards and that expense had to ensure protection of the roughly 50 residences identified as being flood-prone.
Computer modeling also indicated that while residents north of the floodwalls on Maplewood Road won’t see less impact during major flood events, construction of the walls won’t make things worse, either.
Zuercher said the Army Corps of Engineers could be open to researching the costs and benefits of extending the flood wall all the way to 31st Street. However, it’s unlikely that residents of Maplewood Road whose homes front the river would support such a wall.
The Army Corps’ April 5 presentation also revealed that it would be the village of Riverside that would have to negotiate the sale of property along rear edges of parcels along West Avenue, and that eminent domain is one tool that might be used to secure it.
Asked whether that might happen by a resident, Village President Ben Sells said, “I think we’d have to cross that bridge when we come to it. Let’s hope it doesn’t come to that.”
Construction could take a full two years, said Zuercher, although it would be staged and not ongoing in one place that entire time. However, the Army Corps would need construction easements in the rear of West Avenue homes and heavy machinery likely would be working in people’s backyards, causing damage that the Army Corps would have to repair.
In response to other suggestions by residents, Zuercher revealed that realigning the piers of the railroad bridge to improve the river’s flow would not create a benefit that was worth the cost.
He also batted down calls for river dredging to eliminate what one resident referred to as a “chokepoint” where the channel narrows. During major flood events, the river overflows narrow channels just as it did the dam prior to its removal in 2012.
Sells said the village would provide more information, including modeling scenarios on the village’s website and that there would be ample opportunity in the future for resident input.