Environmental Science & Engineering - www.esemag.com - November 2005
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Taking the bite out of infrastructure costs at Ontario’s “Big Apple”
By Duane Smith
Municipalities aiming to
attract higher assessment
uses and new businesses
to a community often face
difficulty in providing water and
wastewater services to a new or
expanding industrial park. Without
these services expansion plans can get
derailed and new commercial/industrial
businesses are less likely to take up
occupancy.
Providing full services to an industrial
park typically requires the municipality
to commit to a large initial capital
investment in an environment
where slow growth may occur. In addition,
municipalities will have to assess
any limitations to their existing surplus
sewer capacity at their wastewater
treatment plant. Where capacity is limited,
municipalities have to consider
whether it is prudent to give up the surplus
to existing users on private services,
only to face the possibility of having
to turn down new higher assessment
developments that might come
along in the future.
This was precisely the dilemma
faced by Cramahe Township during an
expansion of its Colborne Industrial
Park, located adjacent to Highway 401
between Kingston and Toronto and
notable for the “Big Apple” area landmark.
Current tenants of this Industrial
Park include CCC Plastics, a manufacturing
facility, a PetroCanada gas station
and car wash, a transformer manufacturing
facility, a greenhouse, a
dairy and other fuel, transport and distribution
companies.
Expansion plans and a second business
park were in jeopardy because
adequate sewer servicing was not in
place. The existing septic systems had
experienced failures and were already
considered to be an environmental risk
due to a high water table and its proximity
to a natural wetland. The
Township wanted to attract new businesses
to the area and was determined
to succeed, even though only a small
number of businesses required sewers
at the time.
The Township explored using conventional
sewers, but costs were an
issue. The Township did not have the
financial ability to fully assume the
cost of expansion. High costs were partly driven by the fact that conventional
sewer installation required that
the roads would be substantially
replaced as part of the construction
program. Affordability and business
operating continuity then became an
issue with both the municipality and
the business owners.
In addition to the capital challenges,
the project would commit nearly
all the remaining surplus capacity of
the Township’s sewage treatment plant
to the industrial park, thereby limiting
future growth opportunities. The
design allowance for infiltration by
employing a conventional sewage collection
system in the servicing plan
had a major impact on the ability of the
downstream infrastructure to accept
both the existing development and
future development. The combination
of these two factors, capital constraints
and limited sewage treatment capacity,
led the municipality to seek other
options for servicing.
After exploring alternative solutions,
the township selected the SBS™
system, a small bore sewer technology
developed by Clearford Industries Inc.
of Ottawa, Ontario.
Effluent in Clearford’s SBS (Small
Bore Sewer) system is discharged to a
network of small diameter (about 10 to
15 cm) HDPE pipes and transported to
a conventional sewer outlet. Piping is
pressure tested and completely sealed,
preventing groundwater infiltration
into the system and reducing the overall
volume of waste transmitted ultimately
to the treatment works. An onsite
clarifier at each building collects
solids and provides primary treatment
of the sewage prior to entering the collection
system. The clarifier has been
designed for a recommended 7-10
years cleanout cycle for the settled
solids and also serves to stabilize flows
to reduce system peaking factors.
Combined efficiencies of the sealed
system, stabilized flows and solid separation
allow system owners the flexibility
to reduce the size of their downstream
collection works and realize
cost and operating efficiencies not
available to them by employing historical
wastewater collection solutions.
The system helped the Township to
solve its challenge of providing serviced
industrial land within tight financial
constraints and within the limits of
available capacity at its wastewater
treatment plant. The key benefit of the
low-flow SBS system was the reduced
initial capital and lower ongoing operating
costs. An additional benefit of
the SBS system is that it can be
installed using horizontal drilling
methods, resulting in substantially
reduced disruption to existing business
activities and road surfaces.
Clearford was awarded a design-build
contract for under $400,000,
about 40% less than the original estimate.
Under the design-build arrangement,
Clearford became the single
source of accountability for the project.
It was constructed over the winter
months, with spring installation of the
tanks. A one year warranty was included
in the contract. Clearford worked
with all of the occupants of the industrial
park to determine their water
usage and service requirements and
designed the system to ensure that all
of their expressed requirements would
be met.
Since the installation, Clearford has
engaged PCL Constructors as its
national supply partner for construction
and project management services. The
partnership will combine Clearford’s
wastewater design capabilities with
PCL’s bid and build expertise to provide
municipalities and developers with
fixed price solutions and strong guarantees
for their sewage and water
requirements.
Small bore sewers have also been
effectively installed in areas where
septic tanks are failing in communities,
infrastructure needs upgrading, or
municipalities are in need of development
or are near capacity with their
wastewater treatment plants.
The small bore sewer system in the
Colborne Industrial Park is the first
installation of this kind in Canada for a
commercial/light industrial application.
With the system initially commissioned
in 2004, the park is now entering
into a new phase of development.
Private developers also have an
interest in the technology because it
allows for increased housing densities
in areas that would otherwise have
large lot sizes due to septic leach field
requirements.
Duane Smith is Research Director for
Clearford Industries.
Contact: dsmith@clearford.com
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