THE CHALLENGE: After years of struggling for a solution to their water
supply source treatment requirements, the Portland Connecticut Water Division achieved a
solution through an interconnection with the Metropolitan District Commission (MDC).
THE SOLUTION: The initial process of the interconnection was to determine the physical and
financial feasibility. The Portland water system was modeled to determine what system improvements
would be required to connect to the Metropolitan District. Water mains of each Authority were
in economical proximity to one another, but system improvements were required to convey the 2-mgd
flow required for Portland's current and future needs. The modeling study identified size and
location of new transmission mains and storage tanks as well as required hydraulic grade lines
for a booster pumping station in the Metropolitan District system. With the required improvements
considered, project costs were estimated and an economic analysis made for the project..
With a firm understanding of the costs and benefits, the Town of Portland negotiated a
long-term contract with the MDC and proceeded with co-applicant MDC in the pursuit of a Diversion
permit from the Connecticut Department of Environmental Protection. Obtaining this permit was a most
critical element to this project's success. Nathan L. Jacobson & Associates, Inc. provided technical
support to the Portland Water Division through this lengthy process and negotiations with stakeholders.
Once the permit was issued, the preparation of the construction contract documents was begun.
Contract 1 was a construction contract for approximately 1-1/2 miles of 16-inch diameter water transmission
main in two different Portland locations. Nathan L. Jacobson & Associates, Inc. prepared the contract documents
and provided construction inspection and administration services.
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Contract 2 was a construction contract for approximately 1-mile of 16-inch diameter water transmission main in
Glastonbury with a meter and valve chamber constructed on the Portland / Glastonbury Town line. The MDC
provided administration of this contract.
Contract 3 was issued for the construction of two 0.5 million gallon water storage tanks. Steel tanks with
a three-coat interior epoxy paint finish and a cathodic protection system were chosen for the application. The
access drive to the tank site required construction of a timber bridge with 25 foot clear span over Reservoir Brook.
To preserve distribution system water quality, recirculation pumps were provided to promote turnover of the tanks and
chlorination facilities were provided on the site. The contract included a control system for tank level monitoring
and control of a well pump and an electric butterfly valve at the connection to the MDC. The system provides for
remote monitoring of flow obtained from the MDC, tank level, and chlorine residual at the tank. Nathan L. Jacobson
& Associates, Inc. prepared the contract documents and provided construction inspection and administration services
as well as start-up services.
After 16 months of construction, the project was completed in 2000 at a cost of approximately $3.0 million.
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