About the Metropolitan Water Reclamation District

I believe we have a chance to show that people can live in a sustainable and harmonious way in and around a living wilderness; that we can be caring stewards — not merely users and abusers of these natural resources; that the Chicago region can have both a sound economy and a healthy ecology. But we have to have leaders who can take this message to the public.

The MWRD should be a leader in this effort.


The Metropolitan Water Reclamation District of Greater Chicago is a little–known agency with a vital mission. Established by the Illinois State Legislature in 1889 as the Chicago Sanitary District, this new agency was charged with protecting the drinking water supply for the burgeoning metropolis of Chicago. At that time, Chicago residents sent all manner of human, animal and industrial waste directly into the Chicago River, which flowed into Lake Michigan. Storms often sent this polluted water toward the intake pipes providing the city’s drinking water — an unsafe and untenable situation.

The city planners and engineers of the time conceived of a plan to reverse the flow of the Chicago River by digging two large canals and building a lock at the mouth of the Chicago River, essentially using lake water to flush the city’s sewage downstream. This massive scheme was completed in 1900. (Read more about Chicago’s flood and drainage control.) For nearly 30 years, this system of canals and channels were literally open sewer pipes conveying waste down river and serving as a route for commercial barge traffic between the Mississippi River and Lake Michigan.

By the late 1920s, more modern techniques of sewage treatment had been developed and the Sanitary District ultimately built seven wastewater treatment plants around Cook County, including what is regarded as the world’s largest at Stickney, implementing modern sewage treatment for the city and suburbs. The District’s service area for sewage treatment expanded to include almost all of Cook County — Chicago and 125 suburban municipalities — serving 5.3 million residents and industry and processing more than 1.5 billion gallons a day of wastewater. The annual budget now totals more than $1.3 billion. The agency changed its name to the Metropolitan Water Reclamation District at its centennial in 1989.

Another major turning point in the District’s history — and a signal achievement — was the development of a plan to capture billions of gallons of stormwater overflow in a huge underground tunnel to reduce pollution in the Chicago waterways. Called the Tunnel and Reservoir Plan (TARP), but popularly known as Deep Tunnel, this multibillion–dollar project was begun in the late 1960s. The tunnel portion — 109 miles burrowed in the deep limestone bedrock — was completed in May 2006 and has captured billions of gallons of stormwater overflows, reducing pollution in the waterways and contributing significantly to improved water quality.

The Majewski Reservoir located near O’Hare Airport was completed in 1998 and can capture up to 325 million gallons of stormwater overflow. The Thornton Reservoir, part of a limestone quarry visible from I–80 near Hodgkins, will be completed in 2015. When fully operative, the Thornton reservoir will hold approximately 7.9 billion gallons of stormwater, reducing combined sewer overflows for nine villages. The McCook Reservoir, adjacent to I–55, is being excavated and will be completed in two stages. The first stage, due to be finished in 2017, will capture 3.5 billion gallons of stormwater overflows. The second stage, bringing the total capacity to 10 billion gallons, will be completed in 2029.

When these reservoirs are fully online, CSOs into the Chicago waterways should be eliminated or significantly reduced.

However, we are witnessing increasingly intense rainstorms in northeastern Illinois that I believe may be a symptom of climate change. (The Intergovernmental Panel on Climate Change’s report suggests that the Midwest may see a change in the period of rainfall and more intense rain events, but not necessarily more overall precipitation.)

The sewer and water pipes laid beneath the streets in every village and town in Cook County are owned and maintained (or should be) by each municipality. The 554 miles of larger interceptor pipes owned conveying wastewater and stormwater to sewage treatments plants are owned and maintain by the MWRD. But the local pipes are generally designed to hold as much water as is produced by a five–year storm — what is calculated to be 3.8” in a 24–hour period.

The more severe storms afflicting Cook County have dumped far more rain in a shorter period of time, overwhelming the capacity of any local sewer system to deal with them. The result? Widespread flooding and basement backups; property damage and ruined goods.

In 2004, the Illinois General Assembly granted authority to the MWRD to manage stormwater for Cook County, with an additional taxing authority (up to $46.6 million in the 2015 budget). Stormwater management takes the District aboveground and into people’s homes and businesses in a way that sewage treatment had not.

The challenge we face is this: Will the MWRD see itself as a garbage collector, gathering a waste product (stormwater) and disposing of it by sending it into the sewers where it gets contaminated by mixing with sewage? Or will the MWRD see itself as a bank, collecting deposits of precious liquid assets (rainwater) and investing them wisely in our communities?

In 2013, the District adopted a Watershed Management Ordinance for Cook County that sets minimum standards for retention and detention of rain on sites where development and redevelopment is taking place both to prevent additional flooding and to enhance water quality in area waterways. Additionally, the ordinance should help to reduce future flooding by promoting use of green infrastructure, a suite of techniques such as rain gardens and green roofs that seek to mimic the way nature works.

As with most public agencies, the MWRD faces significant budget challenges — an unfunded pension obligation, rising health care costs for employees and energy costs for operations, aging infrastructure and declining revenues. Unlike most utilities, which charge fees for the services they provide, the Water Reclamation District’s operating budget — roughly $450 million in 2014 — comes principally from Cook County property taxes. While the District’s tax base is broad and diverse, permitting it to earn and retain two AAA bond ratings, a tax cap, limiting its ability to generate new revenues, also binds the agency. (MWRD’s total 2015 budget, including capital projects and revenues from leasing of land, user charges, and a few other sources, came to $1.2 billion.)

Such challenges also provide opportunities for MWRD to remake itself as a resource recovery agency, converting solid waste to energy and looking for ways to reuse the water leaving its treatment plants.

The Facts…

…About Water and Water Use

  • As Midwesterners, we are in charge of a unique and precious resource. The five Great Lakes contain about 90 percent of the U.S. water supply and 20 percent of the world’s fresh surface water. The lakes hold 5,500 cubic miles, or 6 quadrillion gallons, and span more than 94,000 square miles. Only the polar ice caps contain more fresh water.
  • Lake Michigan, the second largest in volume, is the only Great Lake entirely within the United States, making it one of the region’s most magnificent treasures.
  • Most people use between 70 and 100 gallons of water a day.
  • Flushing a toilet uses between 2 and 7 gallons of water. To reduce the amount of water required to flush, you can add a displacement device (a water-filled plastic bottle or bag) to your tank. Even better, replace an older toilet with a new dual-flush model.
  • Washing dishes by hand uses about 5 gallons per person; A dishwasher uses 9–12 gallons per load.
  • A shower uses 2–5 gallons a minute; a bath uses about 50 gallons.
  • Most people use about 2 gallons to brush their teeth.

…About the MWRD

  • The Metropolitan Water Reclamation District of Greater Chicago (MWRD) treats an average of 1.4 billion gallons of wastewater every day and has the capacity to treat over 2 billion gallons a day.
  • A staff of 2,000 work under the direction of an executive director and nine elected commissioners to carry out this mission.
  • The District serves 5.3 million people — plus the commercial/industrial equivalent of 4.5 million people, and a combined sewer overflow equivalent of .5 million people. That’s the equivalent of 10.1 million people!
  • The District serves an area of 872 square miles, which includes the City of Chicago and 125 suburban communities. The District's 547 miles of intercepting sewers (large pipes underground) range in size from 12 inches to 27 feet in diameter, and are fed by approximately 10,000 local sewer system connections.
  • The treatment plant in Stickney, one of seven owned and operated by MWRD, is the largest wastewater treatment plant in the world. It serves 2.38 million residents of Cook County.
  • The District's Tunnel and Reservoir Plan (TARP, aka “Deep Tunnel”) is one of the country's largest public works projects for pollution and flood Control. 96 miles of tunnels, 9 to 33 feet in diameter and 150 to 300 ft. underground, have been constructed and are in operation.
  • The District controls approximately 76 miles of navigable waterways, which are part of a national system connecting the Atlantic Ocean and the Great Lakes with the Gulf of Mexico.
  • Sidestream Elevated Pool Aeration (SEPA) Stations add oxygen to the waterways by lifting the water and allowing it to cascade over a series of waterfalls. These "urban waterfalls" increase the dissolved oxygen in the water, thereby improving the quality, aesthetics, and aquatic environment of these waterways.
  • The MWRD also runs the Biosolids Disposal and the Prairie Plan. The District's water reclamation processes produce a by-product known as biosolids (what used to be called "sludge"). Biosolids consist of solids that are removed from the wastewater and are processed by various methods to produce a stabilized, nuisance-free product suitable for disposal.

…About Our Region’s History of Water Reclamation

  • From 1833 (when Chicago was incorporated as a Village) to 1855, Chicago had no sewers. Waste flowed into streets and ditches.
  • During the period 1860–1890, Chicagoans suffered from epidemics of typhoid fever and cholera. In 1889, the Illinois legislature passed an Act establishing the Sanitary District of Chicago. In 1892, ground was broken to construct the main channel of the Sanitary and Ship Canal.
  • In 1900, the main channel of the Sanitary and Ship Canal was completed and the last barrier between the Des Plaines River and Lake Michigan was removed, reversing the flow of the Chicago River. Water was diverted from Lake Michigan to dilute sewage and flush it downstream. In 1911, the North Shore Channel was built to divert more lake water to aid dilution. Interceptor sewers were completed, and Lake Michigan was largely protected from contamination.
  • In 1985, the District’s 31-mile Mainstream tunnel system began operation; it is capable of storing one billion gallons of combined sewage and storm water.
  • In 1986, the District's TARP tunnel system (“Deep Tunnel”) received the National Award as "Outstanding Civil Engineering Achievement of 1986" from the American Society of Professional Engineers. The District's 9.2-mile Cal-Sag segment of the Calumet Deep Tunnel began operation.
  • In 1989, the District celebrated 100 years of protecting water. As part of the Centennial Celebration, the District changed its name to the Metropolitan Water Reclamation District of Greater Chicago and built Centennial Fountain on the north bank of the Chicago River at McClurg Court in Chicago. The District also established a 26-mile Centennial Trail along three historic waterways — the Des Plaines River, the Sanitary and Ship Canal, and the Illinois and Michigan Canal. The American Academy of Environmental Engineers awarded its Grand Prize for Planning to the District for the Urban Waterfalls (also known as Sidestream Elevated Pool Aeration stations), which aerate the water in the main and Cal-Sag channels to enhance the aquatic environment, improve and protect fish populations, and reduce odors.
  • In 1991, the MWRD dedicated the first two streamside elevated pool aeration (SEPA) stations along the Cal-Sag Channel.
  • In 2006, the final stage of Deep Tunnel was completed and all 109 miles were placed in operation.
  • In 2007, the Lockport Powerhouse celebrated its centennial. The District still generates hydropower from turbines located at the powerhouse.
  • In 2011, the MWRD Board approved the installation of disinfection technology to kill more bacteria and other pathogens in the treated wastewater at the O’Brien and Calumet treatment plants.
  • In 2013, the District began planning for a new nutrient recovery project at the Stickney plant to remove phosphorus from treated water and convert it into a slow–release fertilizer that can be sold
  • In 2014, the Watershed Management Ordinance regulating development and redevelopment on parcels of a certain size threshold went into effect.