KINGMAN – Sam Elters of Matrix Design Group presented City Council on Tuesday the construction delivery method analysis for the Rancho Santa Fe Interchange at Rattlesnake Wash project, and his recommendation of using design-bid-build was approved by a vote of 5-2 after much discussion.
Matrix considered three delivery options for the project: design-bid-build, construction manager at risk and design-build. Design-bid-build, the recommendation to Council, entails the property owner contracting with a designer and contractor separately, with the lowest bidder being selected for the work. CMAR also hires a designer and contractor separately, the key being starting the process as early as possible so the two entities can work together and explore options.
Design-build for this project, Elters said, means a contractor would bring on a designer, and the two would become a team for the one contract issued.
There were three “key assumptions” Matrix based their recommendation on, Elters said. The first and second were that the project scope is based on roadway improvements only from Louise Avenue to Industrial Boulevard, and Airway Avenue from Prospector Street to Rancho Santa Fe Parkway, and that the analysis did not consider other infrastructure improvements. The third was “the assumption that project funding would be secured in advance,” through the partnership with the City, ADOT and property owners by the time a contract is awarded.
Matrix’s analysis criteria also took into account that designs for the interchange are 95 percent complete. The design-bid-build is expected to take three to four months to complete designs, whereas CMAR would take four to six months, and design-build seven to nine months.
Design-bid-build is also the least expensive option to complete the project design. However, that option has the highest likelihood of cost escalation that would fall on the City should unexpected issues arise during construction, which was cause for concern for some councilmembers.
“If there is a change order, the risk allocation in a design-bid-build is more with the owner, in this case, it would be with the City and ADOT, Elters said. “In CMAR it’s usually shared, and then in design-build it’s usually allocated in the request for proposal.”
Councilman Travis Lingenfelter, citing his experience with the three project delivery methods, favored design-build.
“The factors that I would say warrant a design-build as opposed to a design-bid-build, the first would be the design, as you stated, still needs to be updated and finalized. The second would be the opportunity to include the funding component in the public procurement competition and not assuming that it’s already available,” Lingenfelter said, which would allow the City to compare teams and their approaches to funding.
He noted a guaranteed maximum price is decided on in design-build, so there is no potential for additional cost to the City.
“With design-build, there’s a low risk of potential surprises,” he said. “Design-bid-build, you’ve got a long stretch of undeveloped property, you could get into a situation with design-bid-build like unforeseen site conditions which leads to costly change orders.”
He also said that in using design-bid-build, there is a risk that the designer and contractor will not work well together.
“And who is the real loser there? It’s the owner,” he said. “And I don’t want to put the City in that position.”
Mayor Monica Gates expressed a different opinion.
“I believe it was at Council’s request we looked to engage Matrix and their team of professionals to come and give the City their very best advice as to how to guide this project along, I think to the tune of well over half a million dollars ($646,000),” Gates said. “My suggestion here is we engaged paid professionals because we are, although all elected, we are a lay body of individuals. We engaged these professionals to bring us their expertise, and I’m curious as to why we’re questioning that expertise.”
Vice Mayor Jen Miles and Lingenfelter voted against Matrix’s recommendation, but Council approved moving forward with design-bid-build as the procurement method by a vote of 5-2.