Pockets in St. Charles still slogging through flood conditions

At 7 p.m. on Monday night, the unusually high waters of the Fox River still swept against the walls separating St. Charles city hall from the soggy existence that remains in several neighborhoods.

But a long-term plan is in place to keep the problematic pockets from seeing similar flooding in the future.

Public Works Director Mark Koenen told aldermen water coming down the river is still making staff members sweat a bit. Koenen said the high water mark recorded on the river so far up in Algonquin will either be the 10th- or 11th-highest recorded in the past 90 years.

“This was a significant rain event,” Koenen said. “We know all that water is going to get to St. Charles sooner or later. The waters are still high.”

Indeed, even after more than a day with no additional precipitation, the Illinois Avenue/Street bridge remained closed Monday. City officials have not been able to investigate the structural soundness of the bridge post flood because the top of the pier is still covered with water. The bridge will remain closed until the water level drops enough for a safety inspection to occur.

Not much has improved in the 7th Avenue Creek neighborhood since the worst of the flooding.

“There is no definition as to where 7th Avenue Creek is right now,” Koenen said. “It’s just one pond of water.”

While there’s not much that can be done now that the floodwaters are there, city officials are working with FEMA at the federal level to create a revised flood insurance study. The flood plain limits delineated in the current FEMA study don’t come close to where water currently stands in the 7th Avenue Creek neighborhood, Koenen said.

That’s not a surprise.

Koenen said city staff members, and the residents who live in the neighborhood, have been aware for some time that the flood study, which impacts insurance rates and plays a large role in how government can fund solutions and management of local flood plains. City staff members had hoped FEMA would conduct a new study last year, but other major disasters in places such as New York, dropped the priority level of the study. Koenen said he hopes the revisions will come sometime this year.

The long-term plan, in addition to the revised flood study, calls for the city to buy up some of the property in the neighborhood and create more green space that can soak up and detain floodwaters in heavy rain events. The city’s plan also calls for larger culverts and expanded storm sewers in that area. Major improvements, however, will require cooperation between the city and the property owners. Much of the 7th Avenue Creek is privately owned.

But what are the chances of a repeat flood event either this year or in 2014? Koenen said the term “100-year flood event” is often misunderstood. In the world of engineering, Koenen said a 100-year event means there is a 1 percent chance of that size of a storm occurring in any given year. In other words, there’s a 1 percent chance everyone who suffered from this flood will be back under water again next year.

“It’s not that it’s only going to happen once every 100 years,” Koenen said.

City staff advised residents to watch the city’s website for updates on flood conditions, including the use of the Illinois Avenue/Street bridge.