HomeMy WebLinkAboutPublic meeting 1 minutes
Idyllwild Stormwater Drainage Diversion Study
Public Meeting #1
Parkview Church, 15 Foster Road, Iowa City
Thursday, February 5, 2015
Meeting Minutes:
Introduction:
Jason Reichart, Special Projects Engineer, City of Iowa City
Brief introduction discussing the format of the meeting: presentation covering the background
and reason for study, study approach, and potential outcomes. Those in attendance welcome to stay and ask questions and discuss project details with City and Design Staff.
Presentation: Michael Ryan, Project Engineer, HR Green
During the study we will look at what can happen with stormwater drainage in the
Idyllwild Development
Will analyze a large variety of storm intensities to determine what happens within the
watershed, identify problem areas within the existing storm sewer system, and develop
recommendations for improvements if necessary
Will look at existing and developed conditions for the watershed north of Idyllwild when
analyzing existing storm sewer system
When creating the computer model historic rainfall data will be used to create design
rainfall events. Typically smaller, more intense rainfall events will be used to analyze smaller watersheds like the one draining into the Idyllwild Development.
The computer model being used in this study is advanced enough that it can model the flow of stormwater through the storm sewer and overland flow simultaneously. This will
allow us to more accurately identify problem areas in the storm sewer system as well as
problems caused by overland flows.
The results of this analysis will allow us to develop cost estimate for potential
improvements.
Q & A:
Q1: Why is the City conducting the Idyllwild Stormwater Drainage Diversion Study? A1: Although City Council chose to not move forward with any alternative from Taft Speedway
Flood Mitigation Study, they did direct Engineering Staff to look into a recommendation to
review Idyllwild’s interior drainage system and offsite drainage patterns Recommendations from the Taft Speedway Study also include rerouting offsite drainage around Idyllwild
rather than through the development to reduce drainage volume and required stormwater
pumping. This Study will look at these recommendations in greater detail, identify issues, and determine how they can be improved.
Q2: What kind of improvements can be made? A2: Drainage swales and new storm sewer could be constructed to divert runoff from large
storm events around the Idyllwild Development rather than through it. Any drainage diversion will have to allow low flow from smaller storm events to pass through the Idyllwild ponds to maintain water quality.
February 13, 2015
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Q3: How will future development to the north be accounted for in the Study? A3: The Design team will look at a variety of situations and make conservative estimates. Development may not take place for years but if issues exist at this time they should be
addressed now. Q4: Who is responsible for addressing stormwater runoff from the development to the north?
A4: The developer of the land will be responsible for stormwater management. However, development may not take place for years but if issues exist at this time they should be addressed now. Results from this study may help determine better stormwater
management techniques to the north improving the overall system as well.
Q5: How can we help with obvious issues like clogged storm sewers?
A5: Notify City Staff of any issues with the storm sewer system when you see them. If the issue is above ground, like a clogged intake, call the City Streets department at
319-356-5181, if the issue is below ground, like a sink hole, call City Wastewater at
319-356-5170.
If there are any other questions please feel free to contact Jason Reichart at jason-reichart@iowa-city.org or 319-356-5416.