The Tunnel and Reservoir Plan (abbreviated TARP and more commonly known as the Deep Tunnel Project or the Chicago Deep Tunnel) is a large
civil engineering
Civil engineering is a professional engineering discipline that deals with the design, construction, and maintenance of the physical and naturally built environment, including public works such as roads, bridges, canals, dams, airports, sewa ...
project that aims to reduce flooding in the metropolitan
Chicago
(''City in a Garden''); I Will
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area, and to reduce the harmful effects of flushing raw
sewage into
Lake Michigan by diverting storm water and sewage into temporary holding
reservoir
A reservoir (; from French ''réservoir'' ) is an enlarged lake behind a dam. Such a dam may be either artificial, built to store fresh water or it may be a natural formation.
Reservoirs can be created in a number of ways, including contro ...
s. The
megaproject
A megaproject is an extremely large-scale investment project.
According to the ''Oxford Handbook of Megaproject Management'', "Megaprojects are large-scale, complex ventures that typically cost $1 billion or more, take many years to develop and ...
is one of the largest
civil engineering
Civil engineering is a professional engineering discipline that deals with the design, construction, and maintenance of the physical and naturally built environment, including public works such as roads, bridges, canals, dams, airports, sewa ...
projects ever undertaken in terms of
scope
Scope or scopes may refer to:
People with the surname
* Jamie Scope (born 1986), English footballer
* John T. Scopes (1900–1970), central figure in the Scopes Trial regarding the teaching of evolution
Arts, media, and entertainment
* Cinem ...
, cost and timeframe. Commissioned in the mid-1970s, the project is managed by the
Metropolitan Water Reclamation District of Greater Chicago
The Metropolitan Water Reclamation District of Greater Chicago (MWRD), originally known as the Sanitary District of Chicago, is a special-purpose district chartered to operate in Cook County, Illinois since 1889. Although its name may imply other ...
. Completion of the system is not anticipated until 2029, but substantial portions of the system have already opened and are currently operational. Across 30 years of construction, over $3 billion has been spent on the project.
History
19th century
The Deep Tunnel Project is the latest in a series of civil engineering projects dating back to 1834. Many of the problems experienced by the city of Chicago are directly related to its low level topography and the fact that the city is largely built upon marsh or wet prairie. This combined with a temperate wet climate and the human development of open land, leads to substantial water runoff.
Lake Michigan was ineffective in carrying sewage away from the city, and in the event of a rainstorm, the water pumps that provided drinking water to Chicagoans became contaminated with sewage. Though no epidemics were caused by this system (see
Chicago 1885 cholera epidemic myth
__NOTOC__
The Chicago 1885 cholera epidemic myth is a persistent urban legend, stating that 90,000 people in Chicago died of typhoid fever and cholera in 1885. Although the story is widely reported, these deaths did not occur.
Lake Michigan was ...
), it soon became clear that the sewage system needed to be diverted to flow away from Lake Michigan in order to handle an increasing population's sanitation needs.
The
Illinois and Michigan Canal
The Illinois and Michigan Canal connected the Great Lakes to the Mississippi River and the Gulf of Mexico. In Illinois, it ran from the Chicago River in Bridgeport, Chicago to the Illinois River at LaSalle-Peru. The canal crossed the Chicago Po ...
was built from 1836 to 1848 to divert some sewage water from the
Chicago River
The Chicago River is a system of rivers and canals with a combined length of that runs through the city of Chicago, including its center (the Chicago Loop). Though not especially long, the river is notable because it is one of the reasons for ...
. In 1900, to improve general health standards, the flow of the main branch of the Chicago River was reversed to drain water from
Lake Michigan, as opposed to having the river flow into Lake Michigan. This further improved the sanitation of Lake Michigan, and helped to prevent further waterborne epidemic scares.
Between 1864 and 1867, under the leadership of
Ellis S. Chesbrough, the city built the two-mile
Chicago lake tunnel The Chicago Lake Tunnel was the first of several tunnels built from the city of Chicago's shore on Lake Michigan two miles out into the lake to access unpolluted fresh water far from the city's sewage.
Waterborne disease in early Chicago
In the ear ...
to a new water intake location farther from the shore. Crews began from the intake location and the shore, tunneling in two shifts a day. Clay and earth were drawn away by mule-drawn railcars. Masons lined the five-foot-diameter tunnel with two layers of brick. The lake and shore crews met in November 1866, less than seven inches out of alignment. A second tunnel was added in 1874.
20th century
The construction of the
Sanitary and Ship Canal (1892–1900), enlargements to the
North Shore Channel
The North Shore Channel is a drainage canal built between 1907 and 1910 to flush the sewage-filled North Branch of the Chicago River down the Chicago Sanitary and Ship Canal. The sewage carrying duty has been largely taken over by the Chicago ...
(1907–1910), the construction of the
Cal-Sag Channel
The Calumet River is a system of heavily industrialized rivers and canals in the region between the south side of Chicago, Illinois, and the city of Gary, Indiana. Historically, the Little Calumet River and the Grand Calumet River were one, the ...
(1911–1922), and the construction of
locks
Lock(s) may refer to:
Common meanings
*Lock and key, a mechanical device used to secure items of importance
*Lock (water navigation), a device for boats to transit between different levels of water, as in a canal
Arts and entertainment
* ''Lock ...
at the mouth of the Chicago River (1933–1938) brought further improvements to the sanitary issues of the time. These projects blocked further amounts of sewage from draining into Lake Michigan. The projects also brought fresh lake water to inland waterways to further dilute sewage that was already in the waterways.
Surrounding farmland also engaged in
flood control
Flood control methods are used to reduce or prevent the detrimental effects of flood waters."Flood Control", MSN Encarta, 2008 (see below: Further reading). Flood relief methods are used to reduce the effects of flood waters or high water level ...
projects. The
Illinois Farm Drainage Act of 1879 established
drainage districts. These districts were generally named for the basin they drained—for example, the
Fox River Drainage District. After
World War II
World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposin ...
, suburban communities began to realize the benefits of separating
stormwater
Stormwater, also spelled storm water, is water that originates from precipitation (storm), including heavy rain and meltwater from hail and snow. Stormwater can soak into the soil ( infiltrate) and become groundwater, be stored on depressed la ...
from sewage water and began to construct separate sewer and storm drainage lines. The primary benefit of wastestream separation is that storm water requires less treatment than sewage before being returned to the environment.
Flood damage grew markedly after 1938, when surrounding natural drainage areas were lost to development and human activity. Serious flooding has occurred in the Chicago metropolitan area in 1849, 1855, 1885, 1938, 1952, 1954, 1957, 1961, 1973, 1979, 1986, 1987, 1996, 2007, and 2008—but most record-setting
crest
Crest or CREST may refer to:
Buildings
*The Crest (Huntington, New York), a historic house in Suffolk County, New York
*"The Crest", an alternate name for 63 Wall Street, in Manhattan, New York
*Crest Castle (Château Du Crest), Jussy, Switzerla ...
s occurred after 1948.
In the 1960s, the concept of Deep Tunnel was studied and recommended as a solution to continuing flooding issues.
Status
Phase 1, the creation of of
drainage tunnels ranging from in diameter, up to underground, was adopted in 1972, commenced in 1975, and completed and operational by 2006. Phase 2, creation of reservoirs primarily intended for flood control, remains underway with an expected completion date of 2029. Currently, up to of sewage can be stored and held in the tunnels themselves while awaiting processing at sewage treatment plants, which release treated water into the
Calumet
Calumet may refer to:
Places United States
*Calumet Region, in northern Illinois and Indiana
**Calumet River
**Calumet Trail, Indiana
** Calumet (East Chicago)
* Calumet, Colorado
*Calumet, Iowa
* Calumet, Michigan
*Calumet, Minnesota
* Calumet ...
and
Des Plaines
Des Plaines is a city in Cook County, Illinois, United States. Per the 2020 census, the population was 60,675. The city is a suburb of Chicago and is located just north of O'Hare International Airport. It is situated on and is named after the ...
rivers.
Additional sewage is stored at the Thornton Composite Reservoir, and the Gloria Alitto Majewski Reservoir near
O'Hare International Airport
Chicago O'Hare International Airport , sometimes referred to as, Chicago O'Hare, or simply O'Hare, is the main international airport serving Chicago, Illinois, located on the city's Northwest Side, approximately northwest of the Chicago Loop, ...
. The
McCook Reservoir was completed in 2017 and will be expanded to by 2029.
Because the reservoirs are decommissioned quarries, construction has been delayed by decreased demand for the quarried gravel. Upon completion, the TARP system will have a storage capacity of .
Reservoirs
Effects
Severe weather events have forced water management agencies to pump excess wastewater into the lake and river in order to prevent flooding. These incidents have decreased in frequency as more of the Deep Tunnel system has become operational. Long considered an open sewer, the Chicago River now hosts more than 50 species of fish and increased wildlife along its shores. Substantial development is occurring along many portions of the riverfront. Canoeing is once again allowed on the waterway, but swimming is still prohibited due to high pollution levels.
On October 3, 1986, a heavy thunderstorm drenched the southern portion of the Deep Tunnel area with several inches of rain in a short period of time. While the Deep Tunnel system performed satisfactorily by absorbing excess water, water within the system itself rushed past the north side of Chicago and near the
Bahá'í Temple in
Wilmette
Wilmette is a village in New Trier Township, Cook County, Illinois, United States. Bordering Lake Michigan and Evanston, Illinois, it is located north of Chicago's downtown district. Wilmette had a population of 27,087 at the 2010 census. The ...
.
Geyser
A geyser (, ) is a spring characterized by an intermittent discharge of water ejected turbulently and accompanied by steam. As a fairly rare phenomenon, the formation of geysers is due to particular hydrogeological conditions that exist only in ...
s of over were reported in both locations for up to an hour as the water was redistributed more evenly through the system. A geyser erupted downtown at the corner of Jefferson and Monroe, trapping a woman inside her car as it filled with water.
A system of watertight bulkheads has since been installed to prevent the event from occurring again.
During the
Chicago Flood of 1992, the water from the Chicago River that leaked into the long-disused
underground freight tunnel system was eventually drained into the Deep Tunnel network, which itself was still under construction.
Sources
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References
External links
Set of photos of the Morrison Knudsen segment of the tunnelMetropolitan Water Reclamation District of Greater ChicagoVideo of TARP on YouTubeVideo of TARP on YouTube
{{DEFAULTSORT:Tunnel And Reservoir Plan
Government of Chicago
Buildings and structures in Chicago
Flood control projects
Flood control in the United States
Waste processing sites
Planned developments
Engineering projects
Proposed infrastructure in the United States
Tunnels in Illinois
Proposed tunnels in the United States