ALTERNATIVE DELIVERY METHOD FOR A SANITARY RELIEF SEWER, CITY OF SALEM, OREGON
This paper will describe the steps taken by City of Salem to implement an alternative delivery approach for this project, the preparation of the Request for Proposal for the Construction Manager/General Contractor (CM/CG), the project approach during design and construction,
and the successes and challenges regarding this approach.
On August 26, 2002, the City of Salem, Oregon adopted the Willow Lake Treatment Plant Facilities Plan (Facility Plan). The Facility Plan provided for compliance with the Mutual Agreement and Order (MAO) between the Department of
Environmental Quality (DEQ) and the City of Salem, executed January 5, 1998. The MAO required the City to eliminate sanitary sewer overflows to tributary streams of the Willamette River for up to a 5 year winter design storm and 10 year summer design storm. One element of the MAO required
the City to eliminate Sanitary Sewer Overflows (SSO=s) to Pringle Creek by December 31, 2004 (Pringle Creek is a tributary stream of the Willamette River and is located at the southern end of the heart of downtown Salem, Oregon). The Facility Plan determined that additional interceptor
capacity was required in the downtown area of Salem to eliminate SSO=s to Pringle Creek for storms greater than the design storms specified in the MAO. The solution was to build a new interceptor in the core downtown area of Salem. The interceptor was named the Downtown Interceptor
The project team (City and Consultant) determined that the conventional design-bid-build construction delivery approach would not likely deliver the DTI on time, consequently other delivery methods were considered, namely design-build (DB) and CM/GC. To use an alternative delivery
approach, the City was required to follow the process to provide an exemption from traditional competitive bidding as outlined in ORS 279.015. The City needed to adopt a finding that it was unlikely the exemption would encourage favoritism in the awarding of public contracts or substantially
diminish competition. Additionally, the City needed to show the award of the contract pursuant to the exemption would result in substantial advantage for the City. Consequently, the City staff prepared a report that showed the CM/CG approach would meet these requirements based on the following
The time constraint set forth in the MAO,
The complexity of the specialized construction requirements related to the size and depth of the pipe, and
difficulty in adequately addressing the interests of the property and business owners in the project (downtown) area.
In general with the CM/CG delivery method, the owner engages a design consultant to provide design services and engages a CM/CG
to provide preconstruction services related to construction methods, sequencing, cost estimating, and value engineering. In addition, the CM/CG holds the construction contract and during the procurement process, provides a Guaranteed Maximum Price (GMP) for the project.
documents prepared for the CM/GC delivery method included an itemized bid tab for the CM/GC=s cost related to installation of the 48-inch DTI, without materials such as pipe, backfill, manholes, etc. Allowances were setup to cover these and other items such as design changes,
changed conditions, paving, flagging, and so on. The CM/GC was required to advertise and get competitive bids on materials and labor for all items not included in the bid tabulation.
The CM/GC assisted the design team with the route selection through final design. This approach
permitted early construction packages to be released prior to finalizing the DTI design. The net result was that the project was completed four months ahead of the MAO required date and significantly under the City's capital improvement budget.
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