Design-Build Aspects of WSDOT Projects

DOTs in Oregon and Washington are making projects less complicated by relying on design build contracts that leave most of the planning and design in the hands of private industry.

by Adrian MacDonald

Seven years ago, the Washington State Department of Transportation tested its first pilot project using the design-build delivery method. Now, the department has about $1 billion in design-build projects under way, and is set to expand its use of the method as transportation work continues to heat up.

Proponents of design-build say the projects—including a $217-million contract for HOV lanes on I-5 in Everett, a $1.4-billion program of improvement projects along the length of I-405, and the $615-million Tacoma Narrows Bridge — are being built faster and with more innovation than they would be under the traditional design-bid-build approach.

Fred Tharp, WSDOT’s assistant construction engineer for design-build, says the central advantage to the department in using the method is that DOT doesn’t need to significantly ramp up its design and construction management staff.

“As a government agency we don’t hire and fire people with great frequency, we’re pretty static,” Tharp says. “With design-build, many of our responsibilities as owners are transferred to the design-builder.”

Atkinson is design-builder for the Everett project in a joint venture with CH2M Hill of Bellevue, and recently won another design-build contract for $124 million in improvements to I-405 in South Bellevue.

“There are inherent efficiencies in the design-build contracting method that allow the industry as a whole to deliver transportation projects in a shorter period of time and with fewer overall work hours than the traditional design-bid-build methods,” says Bob Adams, vice president for Guy F. Atkinson of Bellevue.
Adams says one of the inherent efficiencies of design-build is that when a private company is hiring to staff a new job, it can choose people specifically geared to the way it builds a project. In traditional design-bid-build, where the owner completes the design before sending it out to bid, the owner’s staff has to be more generic and work harder to accommodate the style of all potential contractors.

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“For example, we may prefer pre-cast concrete structures, where another firm might be into cast-in-place or steel frames,” Adams says. “With design-bid-build, the DOT might have to design all three.”

Contractors agree, however, that design-build is best on large projects.

“It takes a critical mass of project size to be able to afford a design-build team that has all the necessary features,” Adams says. “It doesn’t make sense on small stuff. There’s too much burden in terms of overhead and indirect cost.”

A design-build team for a WSDOT project typically includes design and construction in addition to quality assurance and quality control, materials documentation, freeway maintenance, environmental inspection, and public relations. On traditional projects, WSDOT staff and consultants would provide many of these services.

In summer 2006, the state legislature passed a bill allowing the department to test design-build on projects as small as $2 million. Previously, the method was only allowed on projects of at least $10 million. To date, the department has not used its new authority.

Tharp says that when the legislature made the $10-million cutoff in the late 1990s, “industry was concerned that we would impact their 'bread & butter' projects if we allowed all projects to be design-build.” He adds that the new allowance is intended primarily for electrical-mechanical retrofits, simple paving jobs, and projects where the department would otherwise have to outsource the engineering.

For smaller contractors, gearing up to bid a design-build project can be a challenge. On WSDOT’s first design-build pilot project in 2000, Max J. Kuney Construction of Spokane won the $23 million contract by teaming up with the engineering firm Entranco of Bellevue, which was acquired by DMJM Harris in 2005. The project was a single point urban interchange on State Route 500 Thurston Way in Vancouver, Washington.

Unlike typical public bidding, the design-build regulations do not require WSDOT to take the lowest bidder. The department assesses bids on both price and technical score—although observers say the low bidder has won all the department’s projects so far.

WSDOT offers a stipend to the losing bidders, although Kuney says this is normally less than half the amount of money a team puts into a proposal. With the stipend, the DOT essentially buys the losing proposal “in case there’s any good ideas in there,” Kuney says.

Once a team wins a bid, it then takes on a much higher level of risk on the project than it would if a contractor  only executed the design drawings, say experts.

“The risk of mistakes in your plan lies with you, not with DOT,” says Kuney. “It’s just part of your evaluation. Reward is commensurate with risk. There’s a contingency in addition to your usual markup. Every team has its own theory. You might spend your contingency and not make any more money.”

Adams says one of the biggest risks a design-builder takes on is quantities of materials. Where in a traditional project the DOT would pay for the actual amount used of materials like asphalt—however off it may be from the estimate—in design-build projects the design-builder pays for any shortage or surplus.

“Sometimes it’s a problem for us, but you do the best you can,” Adams says. “You estimate the best you can, and set up internal controls.”

But one of design-builders’ favorite aspects of the process is how much room it leaves for creativity on the project.

“The DOT is actively looking for innovation,” says Tim Weckerlin, senior project engineer with Kiewit-Pacific’s Pacific Structures group in Renton, Wash. “That’s the fun part, from my perspective. It’s a fun challenge to do it better and quicker, while you still fulfill the basic configuration.”

As design-builder for a $47.5-million phase of road widening work on I-405 in the Kirkland area, Kiewit-Pacific put together its project team by creating an internal joint venture of its Pacific Structures, Northwest, and General Construction divisions and drawing staff from its offices around the country.

Weckerlin says the biggest innovation on that project was a way to realign Forbes Creek—which runs underneath the roadway through a culvert—into a more natural stream. At the start of the project, the culvert had a 3-foot outfall that blocked fish passage, and the most obvious solution was to install a fish ladder to meet permit requirements.

“We realized we could use a series of natural pools to mitigate the elevation difference and take out the ladder,” Weckerlin says.

Since the Kirkland section of I-405 runs through a built-up urban area, reducing impact to third parties was also a prime consideration and another source of innovation. “There’s ways you can shift the alignment to reduce the impact,” Weckerlin adds. “As the designer we have the power to do that.” The design makes extensive use of noise walls and retains as many trees in the corridor as possible.

On the South Bellevue portion of I-405, Atkinson is finding throughout the design-build process ways to shift alignments and geometries to save time and money. In one section, plans called for widening the roadway to the median. Instead, the team discovered it could widen to the outside lanes, saving itself the construction of a soil nail wall and the relocation of a sewer main. The team also was able to shorten a bridge over I-90 and replace the spans with mechanically stabilized earth walls.

“It’s constantly evolving,” says Adams of WSDOT’s design-build program overall. WSDOT maintains a review committee comprising members of the Associated General Contractors of Washington and the American Council of Engineering Companies. Adams and Weckerlin are members, and Kuney is co-chair.