Environmental Science & Engineering - www.esemag.com - November 2004
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Thames Centre builds new water treatment plant to meet new regulations
The Municipality of Thames Centre needed to build
a new water treatment plant and two water tanks, in
Dorchester, Ontario, in 2003, in order to meet
requirements for water under new regulations.
The Municipality had previously provided chlorination
and iron sequestering through the use of a small water
treatment plant. The plant did not provide enough treatment
for the anticipated growth of the community. In the
event of a power loss, the plant could only provide enough
water for one hour at peak flow rates. Additionally, the
water system did not provide enough chlorine contact time
under the new regulations.
While dealing with these issues, the Municipality hired
Stantec Consulting Ltd. from London, Ontario, to design a
new water treatment plant. The new water system provides
water for approximately 1,750 households or 5,500 people
in the Municipality. Also in the event of a power loss, the
new water reservoirs can provide enough water for 2-3
days at peak flow. The new rated capacity of the plant is
approximately twice the old plant and still provides chlorination
and iron removal rather than iron sequestering.
During the design stage, it was decided that the treated
water would be stored in glass fused to steel tanks due to their long life and cost-effectiveness. The tanks were
designed, sold and constructed by Greatario Engineered
Storage Systems of Innerkip, Ontario and were manufactured
by Engineered Storage Products Company (formerly
A.O. Smith) of Dekalb, Illinois. Temcor of Carson,
California, manufactured the aluminum geodesic domes.
The new system still did not provide adequate contact
time before the first user, so internal baffles were designed
and installed in the glass fused to steel
reservoirs. Notably, there are 120
sheets of glass fused to steel required
to build each tank and 80 sheets of
glass fused to steel inside each tank to
act as the baffle walls. The baffles
were specifically designed for contact
with potentially freezing water in
order to resist the spalling process.
Each side of the steel sheet was coated
with cold climate glass that is inherently
white in colour.
The curtain-wall baffles were
designed to meet a baffling factor of
0.5 under the new regulations. The
baffling calculations were provided by
Abacus Engineering of Stayner,
Ontario, and the tanks are used for
potable water storage and chlorine
contact time.
The complete water treatment plant
was built for $4.2 million by Envirocon
Ltd. of Guelph, Ontario, of which
$1.6 million was funded through the
OSTAR program and the remainder of
the money was debentured and paid by
the users.
Article by Scott Burn, Greatario
Engineered Storage Systems,
with the
help of Steve McAuley and Jarod
Craven, Municipality of Thames
Centre.
Contact, e-mail: sburn@greatarioengsys.com
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