A public meeting was held on October 27, 2014 to explain the finding of the research done on the August 22, 2014 storm event. The meeting focused specifically to the west portion of the Ridgewood subdivision and the 5400 block of Franklin Avenue in Springdale. This post includes a summary of the meeting as well as links to the documents presented.
Ridgewood and Springdale are subdivisions in Western Springs with separated sewer systems. A separated sewer system consists of two separate pipes beneath the surface. One pipe carries the waste water from a home while the other is strictly for storm water. In the August 22 storm event, the majority of flooding issues were related to storm water, not sanitary. Ultimately, all of the storm water collected in these two areas of the Village empty into Flagg Creek via sewer outfalls. The August 22 storm dumped 3.0-5.0 inches of rain in a 45 minute duration. This particular event was accompanied by rainfall that measured well above a 100-year storm event. The intensity of this event in such a short duration raised the level of Flagg Creek to the point where the sewer outfalls were submerged.
It is the expectation that water be stored in the Village right-of-way, such as streets and parkways, during large storm events. The water is meant to temporarily sit in these areas until the sewer system can catch up and properly drain. In this event, the water had no where to go with the creek outfalls submerged and therefore found a path into basements and garages. The Village responded by presenting the following information:
- Sewer televising and inlet and catch basin inspections were performed to determine if there was a deficiency in the storm sewer system. There were no issues found that restricted the flow of water.
-JJ Benes & Associates performed a storm water analysis on both of these areas. The documents presented at the meeting for Ridgewood can be found at http://wsprings.com/DocumentCenter/View/1780. The documents for the Springdale subdivision can be found at http://wsprings.com/DocumentCenter/View/1779.
In addition, the Village agreed to further inspect the following issues that were brought forth by residents at the meeting.
-The Village would be reviewing the inlet grates as well as some manhole covers to determine if there were options to increase flow during storm events.
-The Village would be reviewing areas for possible retention pond locations.
-The Village would be researching the flow of water on Howard Avenue and Caroline Avenue to determine how much of it drains onto Franklin Avenue.
Updates will be posted on the Village website to inform residents of the progress of these items. Any questions or concerns about the meeting or the storm event itself should contact the Municipal Services Department at 708-246-1800 x 200.