Boring - Trenchless International

Under Chicago
Chicago, the Windy City, is situated on the south western shores of Lake Michigan and is the
capital of Illinois. The city, founded in 1833, has depended on the lake for water and sanitation.
Here Trenchless International provides an overview of the development of the city’s water and
wastewater networks, as well as looking at current projects.
Water works
North america
April 2010 - Trenchless International
Bordering on Illinois, Indiana,
Michigan, and Wisconsin, Lake Michigan
is the only Great Lake to be located
entirely within the United States. It is the
second largest Great Lake by volume,
with a capacity of 1,180 cubic miles of
water, and the third largest by area.
The City of Chicago utilises Lake
Michigan as its source of drinking water.
Water is treated via two plants – the
Jardine Water Purification Plant serves the
northern areas of the City and suburbs,
while the South Water Purification Plant
serves the southern areas of the City and
suburbs.
Water is distributed throughout Chicago
via century-old pipes that require ongoing
maintenance. The City of Chicago commonly
uses trenchless techniques such
as sliplining and CIPP, together with CCTV
inspection and condition assessment to
inspect and maintain the system. In addition,
the City has implemented the Tunnel
and Reservoir Plan (TARP), also known
as the Chicago Deep Tunnel, which aims
to reduce flooding of the city and prevent
raw sewerage from entering Lake
Michigan by diverting the flow to holding
reservoirs.
In the pipeline –
a short sewer history
The Chicago Sewers Collection has collated
a history of the development of the
wastewater network.
From the establishment of Fort Dearborn
in 1803 along the Chicago River to the
present day, water and sanitation have
always been crucial to Chicago. Chicago’s
low-lying location combined with the livestock
and waste of the settlers resulted
in a serious waste disposal problem. The
Collection states that by 1845, Chicago
was facing an environmental crisis and
then experienced two cholera epidemics.
In 1855, the Chicago City Council
employed Boston engineer Ellis S
Chesbrough to design the first comprehensive
system of underground sewers in
the United States. The Board of Sewerage
Commissioners adopted Mr Chesbrough’s
plan to drain sewage into the Chicago
River, in order to limit the cost and extent
of the proposed sewer system. The level
of Chicago’s streets was raised from six
to ten feet to accommodate sewer pipes,
gas and water mains. Owners lifted buildings
to meet the new street level; in some
cases whole blocks were raised at a time.
By 1930 Chicago’s sewer system
was the most extensive in the world.
Today the Chicago Department of Water
Management continues to employ new
technologies in inspection, materials and
maintenance.
Planning for future
Despite the reversal of the Chicago
River and the construction of the largest
water treatment plant in the world, polluted
combined sewer overflows (CSOs)
persisted in Chicago throughout the first
half of the 20th century.
In 1972, in order to improve the Chicago
Area Waterway System (CAWS), the TARP
was adopted by the Metropolitan Water
Reclamation District of Greater Chicago
(MWRD).
MWRD explained that construction of
Phase 1, primarily for pollution control,
began in 1975 and was completed in
2006. The total length is 176 kilometres
(109.4 miles) of deep, large diameter,
rock tunnels providing 2.3 billion gallons
of volume to capture CSOs. The tunnels
were bored using tunnel boring machines
(TBMs), with pipe diameters ranging from
9–33 feet. MWRD says that the TARP tunnelling
work led to major improvements to
the TBMs, and pushed them beyond their
then-proven capabilities. For example the
Mainstream tunnel was mined three times
faster than the 0.6 metres per
hour that had been estimated
in 1975.
Mining records were set on many of the
TARP contracts. On the last tunnel leg
completed on the Calumet system (Little
Calumet), the TBM crew broke several
world records for a machine of its size.
In addition to contributing to an increase
the speed of mining, the TARP project
has led to improvements in accuracy. The
TBM used on the Little Calumet leg used
a laser target system to permit continuous
steering control and monitoring of line
and grade – a huge improvement from
the machines used on the first tunnels of
the TARP, which had to be adjusted at the
end of each push. Phase 2 of the TARP
is in construction and is expected to be
completed by 2019.
In late 2009, Governor of Illinois Pat
Quinn and Illinois Environmental Protection
Agency (EPA) Director Doug Scott
announced grants and loans for environmental
projects to improve wastewater
quality in Illinois, using funds from the
American Recovery and Reinvestment Act
of 2009 (ARRA). The recovery program
was authorised in 2009 by the United
States Congress and President Barack
Obama. Illinois EPA receives approximately
$US180 million for wastewater
projects and $US80 million for drinking
water projects through ARRA.
The same year the Department of Water
Management completed a city-wide computer
model of its large auxiliary sewers
(42 inches in diameter and larger) and
CSOs. This dynamic flow model represents
the best available information on the
hydrologic and hydraulic characteristics
of the sewer system. The model will be
used as a planning tool to regulate development
and investigate the need for future
sewer projects.
Chicago’s main sewers convey flow
to interceptor sewers. These interceptor
sewers are owned and operated by the
MWRD. The interceptor sewers convey
dry weather flow to MWRD’s treatment
plants for treatment and release to local
waterways. During storm events, flows in
excess of the capacity of the interceptor
sewers discharge into the MWRD’s TARP
system for storage.
Dr A S Paintal, a sewer engineer with
MWRD spoke with Trenchless International
about maintaining Chicago’s sewer
network. MWRD is responsible for approximately
550 miles of the sewer network.
Pipe diameters range from approximately
18 inches up to 24 feet, with the majority
between 5 and 7 feet in diameter. Dr
Paintal explains that, as the sewer network
was built in the early part of the 20 th century,
the engineering department needs
to use trenchless techniques such as slip
lining and CIPP to maintain the network.
Mayor of Chicago Richard Daley says
“We are proud of our efforts to renew
Chicago’s infrastructure with the installation
of new water and sewer mains.”
1803: Establishment of Fort Dearborn,
water is taken from the Chicago River
and private wells.
1834: By the order of village trustees a
village well is dug – the first attempt at a
public water supply.
1836: The Illinois State Legislature
grants a 70 year charter for incorporating
Chicago Hydraulic Company, a
private enterprise, to supply water to the
City of Chicago.
1842: Construction is completed on
Chicago's first water works. The water
mains are made of cedar and the water
intake is located about 150 feet into
Lake Michigan.
1851: The Illinois State Legislature
grants the City a charter to build and
operate its own water works system.
1854: The water system, consisting of 8
3/4 miles of cast iron pipe and one iron
reservoir, is put into operation. The new
intake is made of timber and extends
600 feet into Lake Michigan.
1863: The Chesbrough plan is adopted
to construct intake cribs and deep tunnels
two miles offshore of Lake Michigan
to avoid shoreline pollution.
1867: The “Two-Mile” crib and tunnel
are successfully put into operation.
1871: The Great Chicago Fire.
1889: Annexation gives the City two new
intakes, two new tunnel sections are dug
to serve the northern and southern sections
of the City.
1900: The flow of the Chicago River is
reversed so water is carried away from
Lake Michigan.
1901: The Central Park and Springfield
pumping stations are built in conjunction
with recently completed northwest land
and northeast lake tunnel expansion.
1909: The Blue Island tunnel is put into
service; Chicago’s first long, concretelined
tunnel.
1911: The Edward F Dunne intake crib
for Chicago’s southwest side is put into
operation to supply the southwest lake
and land tunnel.
1912: Chlorination of Chicago’s water
begins on the City’s southwest side.
1918: The Wilson Avenue tunnel and
Mayfair pumping station are completed.
1922: Construction begins on the largest
tunnel to date, in the City of Chicago,
to accommodate the Dever intake crib.
1926: Construction begins on the City’s
south side for Chicago's first experimental
water filtration plant.
1947: Chicago becomes one of the
first cities in the nation to utilise modern
state-of-the-art filtration technology
when the South Water Plant opens.
1964: The James W Jardine Water
Purification plant opens. It is the largest
purification plant of its kind in the world.
North america
April 2010 - Trenchless International
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