In Cook County, the floodwaters that annually fill basements and damage millions of dollars in property have long been managed through a patchwork of efforts by local, state and federal agencies.

Now the Metropolitan Water Reclamation District of Greater Chicago is developing a countywide ordinance that it says will cut down on that flooding by bringing consistency to the way municipalities manage their watersheds.

Progress on the district’s county-wide stormwater management program will provide the focus of a study session at 2 p.m. tomorrow at MWRDGC headquarters, located at 100 E. Erie St. The session follows a regular meeting of the district’s Board of Commissioners that begins at 10 a.m.

Both meetings are open to the public.

Yesterday, the district released updated statistics on its flood control efforts during the record storms that inundated northern and southern suburbs as well as parts of the city from Sept. 14 through Sept. 16.

District officials now place the number of gallons of stormwater released to Lake Michigan through sluice gates at Wilmette, Navy Pier and Calumet at 11.2 billion. That figure is significantly lower than the estimate of 90 billion gallons given during the emergency.

The district’s Tunnel and Reservoir Plan system managed or contained 72 billion gallons of stormwater during what the district is now calling a 112 billion gallon rainfall.

“The 76 miles of manufactured waterways we control did not flood over their banks,” said District General Superintendent Richard Lanyon in a press release. “The areas that did flood saw unprecedented rain into natural waterways and onto saturated land or impervious surfaces that had no where else to flow.”

“It is important we continue working on stormwater management ordinances to cooperatively do everything we can with municipalities to mitigate and prevent similar ruin in the future,” added Lanyon

The stormwater ordinance being considered at tomorrow’s meeting will provide uniform, minimum regulations for managing stormwater in the county,  effectively providing regional regulations similar to those in Du Page and Lake counties.

The ordinance has been in the works since 2007, when the district adopted a Cook County Stormwater Management Plan as an organizational framework. In 2004 the Illinois legislature granted the district authority for stormwater management in Cook County, including areas outside of the district’s boundaries.

The ordinance will encompass concepts like floodplain management, stormwater drainage and detention, wetland protection, soil erosion and sediment control, protection of river habitat and water quality.

The district expects to have a draft ordinance ready for public review by late this year or early next year, says Commissioner Patricia Young, who chairs the stormwater management committee.

A key advisory role in the planning process is played by watershed planning councils that the district established for each of the six major watersheds of Cook County. These include the North Branch Chicago River, Lower Des Plaines Tributaries, Calumet-Sag Channel, Little Calumet River, Poplar Creek and Upper Salt Creek.

Representatives from the councils will report tomorrow on the detailed watershed plans that they’re drafting in conjunction with engineering consultants hired by the district.

Each watershed planning council will eventually propose capital projects that will address key water management problems in their areas.
Projects will be evaluated on the basis of their regional benefits, according to Young.

 “We want to prioritize those projects that will provide the greatest cost-benefit to all of the taxpayers of the county, and not just benefit one community,” says Young.

The city of Chicago retains authority for stormwater management within its boundaries. It’s in the process of negotiating an intergovernmental agreement with the district in order to create a stormwater planning council for areas with combined sewers.

An update on the status of that agreement will also be provided at tomorrow’s meeting, says Young.

The public is encouraged to participate in the stormwater management planning process by contributing comments at tomorrow’s study session and by attending local Watershed Planning Council meetings.