DEERFIELD REGIONAL STORM WATER DISTRICT
SPECIAL DISTRICT BOARD MEETING
February 7, 2007
The meeting was called to order by Walt Daniels at 4:04 p.m.
ATTENDANCE:
Those present at the meeting were:
Board Members: Walt Daniels, Susan Berger, Tim Greive
Engineering (CDM): Jamie Coleman, Chris Calpin, Robert Yoxthimer
Deerfield Township: Larry Weis, Lois McKnight
Watershed Modeling
This was a preliminary meeting to go over CDM’s proposal to create a storm water model for Deerfield Township. The actual proposal will be presented before the DRSWD board at the February 13, 2007 regular meeting.
Mr. Daniels explained that the District asked CDM to put together a proposal to map the Township’s watersheds for both water quantity and water quality. This model could be turned over to Deerfield Township to use in managing development.
Dr. Coleman handed out a document entitled Purpose and Approach that was designed as a lay person’s document to describe the goals and objectives of the model. Mr. Calpin and Dr. Coleman went over the highlights of the document and explained that the Township needed a comprehensive storm water model to protect it when dealing with existing and future storm water management. They went on to explain that the model must be a credible tool in case a developer challenged it, that it must accurately simulate current and future conditions, and that it must be set up in such a way that it can be used as a community planning tool by the Township.
Mr. Calpin and Dr. Coleman went on to explain that they would need to develop a physical representation of the storm water system. They would then use sample storms (at least three of varying intensity) from the past to compile information about rainfall, flooding, and erosion. The model would establish pre-development run-off conditions. Future developers would have to show that their designs won’t change those conditions. The model could also be used to determine Capital Improvement Projects in the Township.
Deerfield Township/DRSWD would own the model. CDM would design it so that Deerfield Township staff could use the model when making development decisions without going back to CDM. CDM would be available to make changes to the model if necessary.
The model would be implemented in phases. The first phase would identify the primary drainage system - open channels in undeveloped areas. The second phase would look at the secondary drainage system (pipes) and integrate existing detention basins and outlet structures. The third phase would be the development of a capital improvement plan that would establish solutions and criteria and levels of service. In a developed area, the model would kick in if someone wanted to change existing structures. The model would show the impact of the changes and also if any problems could be fixed at that time. These implementation phases were also broken down further by watershed. Dr. Coleman handed out a chart showing the various breakdowns.
When asked about a time frame, Dr. Coleman and Mr. Calpin said that if all watersheds were done concurrently, each phase would take about four months or a year to complete the whole model. Times would vary for each watershed if done separately.
Adjournment
Ms. Berger moved to adjourn at 5:29 p.m. Mr. Daniels seconded. All voted yes.
Next Regular Meeting: February 13, 2007.
The Deerfield Regional Storm Water District Board meets the second Tuesday of every month at 6:30 p.m., unless otherwise notified.
Attest:
_________________________________
Susan Berger, Secretary/Treasurer