Essay 2: Stormwater Management

“So the task before us is nothing less than a dramatic change in the way we think about and talk about and manage our freshwater resources. Every time we think about stormwater management, let's think about drinking water management instead. Every time we talk about managing stormwater, let's talk about managing drinking water. Today we treat rainwater as if it were a misbehaving student: We send it to detention. We send it to detention until we can figure out how to get it away from us permanently.

Let me suggest that there is another path. The sustainable cities of the future will be those that are most successful at changing their own culture, that make the transition from viewing stormwater as a problem to viewing rainwater as a liquid asset to be captured, treasured, saved and not squandered.” - Debra Shore MWRD Commissioner 2006

Managing the water that falls to the ground as rain, or snow has been fundamentally connected with the development Northeastern Illinois from its earliest days. Prior to settlement of the region, most of this relatively clean water would soak into the ground and over time become stored in underground aquifers or it would collect in wetlands areas and runoff the land to form streams and rivers that emptied into Lake Michigan or the Illinois River.

As the watershed became developed for agriculture and covered with buildings, roads and houses, the land area available to absorb precipitation was reduced, flooding was common and strategies to move this water more efficiently were adopted. Rivers and streams were routinely channelized, to increase the volume of water they could handle.

To facilitate the movement of stormwater and for sanitary waste disposal Chicago passed ordinances in the Mid-1800’s, requiring that buildings be lifted and backfilled as much as 14 feet above their original level to accommodate the installation of underground sewers.

Today we continue to grapple with managing stormwater, and balancing the need to reduce flooding, and improve the quality of our area surface waters. Because of our success improving the efficiency that we move stormwater, we are now confronting problems associated with both the volume and velocity of the water we dump into the system. Stormwater and CSOs churn up toxic sediments, load excessive nutrients, reduce dissolved oxygen levels, and elevate levels of harmful bacteria and pathogens. On the Chicago River, the Illinois EPA lists stormwater runoff and CSOs as sources of pollution problems or impairments on every stretch of the Chicago River.

The effects of combined sewer overflows on this environment extend far beyond the storm’s immediate consequences. Recent modeling of storm events’ impact on dissolved oxygen (DO) levels in the Chicago River have shown that while volume, strength of pollutant loadings, and frequency of CSOs at a particular location differ dramatically according to the location, intensity, and duration of rainfall events, DO may be impaired in the Chicago River for more than 10 days after combined sewer overflow events in the North Branch, Main Stem, and South Branch of the Chicago River.[i]

To provide some perspective, this means that in 2006, stormwater runoff and combined sewer overflows—in addition to churning up toxic sediments, loading excessive nutrients, and elevating levels of harmful bacteria and pathogens—probably reduced DO levels in some portion of the Chicago River every week of the year.[ii] Reduced DO levels place stress on aquatic life.

In order to best manage stormwater and to eliminate CSOs, we must first complete the phase two TARP reservoirs, and then increase our use of green infrastructure throughout the watershed to reduce the volume and velocity of stormwater entering the sewer system.

TARP is the recognized long-term control plan for reducing CSOs. Friends of the Chicago River[iii] support the timely completion of the Phase Two reservoirs. When it was proposed in 1972, TARP was scheduled to be completed in 1981. Current estimates place the reservoirs’ completion in 2023, 42 years later than originally planned.

We believe that it is time to discuss alternative methods to finance the completion of the Phase Two reservoirs if federal funding before the current proposed date of 2025. It will require $269 million in local funds and $455 million in federal funding.[iv] If the total cost of this project were financed locally, it would cost $36.2 million a year for 20 years.

Managing stormwater in the separated sewer areas.

The North Branch Chicago River (NBCR) watershed is long and narrow, following the shape of three low glacial moraines that run parallel to the shoreline of Lake Michigan. The valleys between these moraines are the current locations of the Skokie River and the Middle and West Forks. Prior to development, the three forks of the North Branch were small streams in relatively undefined channels that meandered through ponds, marshes, wet prairies, prairies, savannas and woodlands. During the late 19^th and early 20^th centuries, the three forks were ditched and the surrounding land was drained for agriculture.

Today, the headwaters of the Chicago River, the northern reaches of the three tributaries, are intermittent in flow and interspersed with wetlands. In the developed areas of the headwaters, fingers of the river originate from surface drainage into underground pipes and ditches. All three forks of the river in Lake County have been significantly modified for drainage. As the three forks of the North Branch flow into Cook County, the character of the North Branch changes to a more natural channel with frequent meandering. The channels of the river grow larger, are more deeply entrenched and wider, as the tributaries flow southward into Chicago.

Based on their active involvement in the watershed, Friends received an Illinois Environmental Protection Agency Section 319 grant in 1996 to develop a more formal watershed partnership and strategy for restoring and managing the North Branch watershed. At this time Friends began an ongoing relationship with the Lake County Stormwater Management Commission (LCSMC) to assist in project activities within the Lake County portion of the watershed. Since 1999 the North Branch Watershed Project (NBWP) has approved 45 projects for $2,441,089 in Section 319 funds, at a total project cost of $9,337,681. All of these projects address impacts caused by stormwater in the 95 square mile NBCR watershed.

In 2004 the NBWP completed work on the North Branch of the Chicago River Open Space (Green Infrastructure) Plan. The Open Space Plan identifies, and suggests appropriate management activities for, parcels in the North Branch watershed that are essential to preserving water quality and enhancing habitat. It is a goal of the Open Space Plan to preserve at least 25% of the watershed as open space to avoid further water quality and habitat degradation.

A key component of that plan was a comprehensive inventory and prioritization of open and partially open parcels throughout the watershed. Once identified, green infrastructure action plans were developed for each parcel that provided direction for stakeholders on actions they can undertake to preserve open space in their respective jurisdictions. In addition to providing direction for how to preserve open space, the plan also specified how open lands can be better managed to provide greater ecological, water quality, recreation and flood damage reduction benefits. The plan also provides a description of best management practice tools and recommendations for restoring and managing natural areas, floodplains and wetlands in a greenway system that also features general locations for recreational trails.

Managing stormwater in the combined sewer areas.

In 2005, the Illinois legislature gave MWRD the responsibility to manage stormwater in Cook County. The MWRD is currently implementing a countywide stormwater management plan and developing a stormwater ordinance.

Historically, watershed planning in the combined sewer areas of Chicago has focused almost exclusively on large, structurally engineered capital projects for flood control, while water quality, habitat, and ecological sustainability have received lower priority.

Over the decades, the design and performance goals of stormwater management techniques have evolved. In the first phase, stormwater control efforts were designed to address flooding and peak discharges from storm events. Over time, water quality management parameters were added to identify controls for all major pollutants found in urban runoff. Now best practices in stormwater management techniques use ecologically sustainable parameters. This integrated approach uses biological, chemical, and physical criteria to define performance.

The watershed plans developed by Friends of the Chicago River and the Lake County Stormwater Management Commission for the separated sewer area of the North Branch of the Chicago River have adopted ecologically sustainable methods in their planning. Many of those control measures will be effective in reducing CSOs in the combined sewer areas. Based on our experience gained controlling stormwater in the North Branch, we believe that as detailed watershed plans are developed for the combined sewer areas they should incorporate the following guidelines.

· Stormwater plans should weigh improving water quality equally with retaining flood water and reducing flood damage. On-the-ground projects that reduce flooding as well as improve water quality should be given preference over single-function projects.

· Increasing the amount of available in-stream and riparian habitat should be a secondary goal of stormwater plans, with preference given to stormwater control projects that increase habitat while reducing flood damage, storing flood water, and improving water quality.

· Stormwater management plans must be built, where possible, around the concept of on-site storage and landscape-based control measures or green infrastructure. · The watershed plans currently under development in Cook County should, within sub-watersheds, include hard numerical benchmarks and goals for reducing the volume and velocity of stormwater runoff that is directed into the sewer system.

· Stormwater plans should identify best management practice(bmp) zones within watersheds and educate the public about appropriate stormwater management techniques for the geology, hydrology, amount of impervious cover, slope, and land cover of each watershed. These bmp zones should have clearly defined numerical targets to reduce the velocity and volume of water entering the sewer system.

· Stormwater management plans must operate from a watershed perspective, as well as create planning partnerships within the watershed that cross political boundaries such as county, city, or state lines when appropriate. Current City of Chicago and MWRD draft ordinances use this perspective.

· Existing watershed and stormwater management plans should be included in the development of new stormwater plans, and opportunities for public input in the stormwater planning process through the watershed councils should be created.

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[i] MWRDGC report 05-12: Verification of a continuous water quality model under uncertain storm loads in the Chicago waterway system, August 2005, p. 102.

[ii] Data from January through July 2006.

[iii] www.mwrd.org

[iv] The federal portion includes a $167 million reimbursement to the MWRDGC for the Thornton reservoir.