Comprehensive Water System –
Joliet, IL
The City of Joliet serves approximately 110,000
customers in northeastern Illinois. It is the largest
water system in the state that does not meet federal
limits for radium in drinking water. We have been
working closely with the City since the mid-1990’s to
meet both quantity and quality requirements.
Program Management
This project deals with every component in the water
system and through the SCADA system, many of the
wastewater collection and treatment systems. The
timing of design, City review, IEPA approvals, and
multiple contractors on multiple sites, while
maintaining full supply of safe water to the City, is a
daunting task.
System Studies
The City considered two approaches to meet its water
needs without violating the radium standard. One
was to convert the system to surface water supply using
the Kankakee River as a source. The second was to
treat and remove the radium.
Radium Removal Process Evaluation
The Radium Removal Process Evaluation included a
reconnaissance-level evaluation of alternatives to
remove radium from the water supply. These included the
Best Available Technology (BAT)’s, lime softening, ion
exchange softening, and reverse osmosis. Other
alternatives evaluated include co-precipitation with
Hydrous Manganese Oxides (HMO’s) and selective removal
using Water Residuals Technology Z-88 and DOW RSC media.
The initial evaluation indicated that removal using
HMO’s would be the most cost-effective and provide the
added benefit of removing iron and manganese as well.
Water Treatment Equipment Design and Procurement
The City wished to package the bidding of the water
treatment plants into several separate construction
contracts. The City also wants to have identical water
treatment and chemical feed equipment at all locations.
To accomplish this, the City bid the treatment equipment
and is assigning the equipment as packages to the
building contractors as they become known. This breaks
the water treatment facilities into units that local
contractors can compete on, but gives the City full
control over the selection and manufacture of treatment
equipment.
Pumping Station Design and Construction
The City has nine booster pumping stations. After system
improvements are made, the Prairie Street and Ruby
Street booster stations can be abandoned. The existing
Bluff Street booster will be removed and replaced with a
5 MGD facility. Two other booster stations will be
upgraded to 9 MGD each, along with replacement of
electrical gear, revisions to the adjacent ground-level
reservoirs, piping, and valves. The pumps at Washington
Street will be upgraded to 2 MGD. The existing Fairmont
and Garvin booster will be demolished and replaced with
a 5 MGD facility that includes permanent and standby
disinfection equipment. The Richards Street booster will
have a pressure sustaining valve added. Only the 1 MGD
Parkwood booster station will not be modified during the
project.
Standpipe Storage
Two standpipes have been constructed in the Joliet Water
System. The Ridge Road System holds a total of 3
mg of water. The Fairmont and Garvin standpipe
replaces two aging reservoirs. Fast-tracked to
eliminate concerns with the existing tanks, this
facility has a volume of 4 mg.
Both standpipes are equipped with a central flow
mixing tube and peripheral baffling to provide better
water turnover, better temperature control, and
conservation of chlorine residual.
Water Main
Route selection was an important consideration during
design. Much of the main runs through fully
developed urban areas. Conflict with existing
infrastructure was minimized during design.
Another aspect of the project was evaluation and
analysis of several hundred thousand feet of Reinforced
Concrete Cyliner Pipe (RCCP). Due to the overflow
elevation of the Fairmont and Garvin standpipe, the
pressure on the pipe was increased. Evaluation
found that the pipe would withstand the increased
service pressure.
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