Bigger pipes, clear culverts need to fix Batavia's flooding woes
Reducing flooding in several southeast Batavia neighborhoods will take larger sewer pipes and better maintenance of drainage culverts, aldermen learned Tuesday night.
And an estimated $2.1 million, just to get the area able to handle the rain from a 10-year-rated rainstorm. Handling the higher rainfalls of a 100-year type of storm, such as the ones that hit in July and in June 2015, would be even pricier, according to an engineer.
A 100-year storm means there is a 1 percent chance of a storm of a certain magnitude happening in any given year.
WBK Engineering studied a 122-acre area in Ward 1 bounded roughly by Pine Street and Giese, Raddant and Kirk roads. The subdivisions were constructed around 1967.
"The design standards are different nowadays," John Witte, an engineer with WBK, said, presenting the report.
Half the stormwater pipes in the area studied are too small to handle even a smaller, five-year rain event, he said. Pipes fill, which leads to water getting backed up and ponding in low spots on roadways. Water has then risen into yards, and flowed into people's houses.
Ward 1 Alderman Michael O'Brien pushed for the city to get a design and price for handling a 100-year storm.
"I just see the weather patterns are changing (more frequent heavy rains), so the standard 10-year design might be kind of outdated," O'Brien said.
"I think designing to a 10-year event is probably underachieving," resident Richard Goebel said.
Compounding the problem is blockages at several of the four drainage culverts under Kirk Road. The water from the neighborhoods is supposed to flow through those culverts to Indian Creek, on Fermilab's property. Indian Creek then takes it to the Fox River.
But two of the culverts are about a third filled with sediment. And water is filling about half of another culvert, indicating there is a downstream blockage, said Andrea Podraza, senior civil engineer for the city,
The Kane County Division of Transportation is responsible for culvert maintenance. Aldermen urged Podraza to increase the pressure on the county to clear the culverts and ditches.
"We need to do it this fall, before it gets worse," Alderman Alan Wolff said.
That may be the easiest task on the list. The rest of the recommendations include putting in bigger pipes, some of which lie under streets, some of which are in peoples' yards.
And any work would compete with other drainage projects throughout the city. The city has estimated there is about $13 million worth that should be done.
O'Brien repeated his support for creating a stormwater utility and charging a monthly fee, to collect money specifically for stormwater projects. And the city should borrow money to do all the projects sooner, rather than piecemeal.
"This (flooding) that is not going away, for all our residents," O'Brien said.
The council will hear Sept. 13 about two other proposed projects elsewhere in the city, including one to separate combined sewers on the near southwest side.