Issaquah SE 62nd Street Extension

2020 CMAA Project Achievement Award
Transportation: Construction value less than $50 Million
Issaquah SE 62nd Street Extension

Owner: City of Issaquah, Wash.  |  CM: KBA, Inc.

The Construction team consisted of the client’s project managers, KBA’s Construction Management team, and the contractor’s project manager and 2 site superintendents for structures and grading. The CM team was the liaison between the client and the contractor. KBA’s ability to track documentation timeliness and cost provided solid back-up for the positions it took on construction issues. KBA developed strong working relationships with both parties.

There were two major value engineering cost proposals (VECP) on the project. The first was initiated by the contractor to change the bridge foundations from multiple small piles to fewer larger ones, resulting in a bridge that could be constructed faster, with less risk and impact on the wetland, resulting in saving the City $877,000. The design also allows for widening the bridge in the future, if needed. KBA’s involvement in the construction phase as an independent party from design was key to acceptance of the alternate proposal.

The second VECP was to change the concrete portals of the East Lake Sammamish Trail undercrossing to gabion rock retaining walls. The idea was collaboratively developed by the Resident Engineer and the contractor’s project manager. The end results were cost savings and better aesthetic blending of the gabion rock walls with the trail environment. The construction was more flexible and easier to build in accommodating necessary transitions that had not been completely designed.  

The City of Issaquah was very engaged with the project while completely delegating the construction management to KBA. The City recognized KBA’s leadership in the project construction management by interviewing KBA’s Resident Engineer in two project videos that described the elements and progress of the project for the general public. The videos were considered a success for the City’s public outreach.
An additional approach to the project delivery was to keep the contractor moving on work where possible. The contractor was often faced with a potential halt with all the changes, either because of time needed to resolve them or because it forced the contractor to change his work sequence. The team continuously worked with the contractor to help to find ways to keep his forces productive, while also working to bring about resolution to the issues.

A unique challenge was working with the Sammamish Plateau Water District on the east side of the project. Their existing sewer line easement in the roadway fell within the preload area. The contract had provisions for replacing the sewer line after the preload was finished. The City and the contractor believed replacement was not necessary after settlement measurements showed minimal settlement at the end of the preload period. There was a small window where the decision had to be made to leave it or replace it to keep the schedule on track. KBA coordinated the effort to objectively examine the effects of preloading on the existing sewer line, including bringing in one of its own experienced staff members from another project to review the results and provide an independent expert opinion.

KBA also endeavored to keep communication channels with the District open during the whole process. The City’s 5-year moratorium on construction through new pavement except in emergencies made the District more risk averse to potential secondary settlement issues with the pipe. The City ultimately decided the potential risk warranted replacing the pipe.