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Maine DOT Finds Success With Portland
Connector
A $25-million bridge connector project
cements state's use of design-build for highway projects
By Sheila Bacon
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The $25-million Portland
Connector project links the Outer Congress Street exit
of Interstate 295 with West Commercial Street and Portland,
Maine's working waterfront. The project was completed
using design-build, shaving nearly two years off the project
schedule.
Photo by Mark Shain |
Completion of a complex road- way construction project in
Portland, Maine, has eased congestion, improved waterfront
access and proven the effectiveness of the design-build process
on highway jobs.
The Maine Dept. of Transportation's use of design-build on
construction of the $25-million Portland Connector-which links
the Outer Congress Street exit of Interstate 295 with West
Commercial Street and Portland's working waterfront-enabled
the project team to bring the roadway to completion nearly
two years earlier than what would have been expected under
traditional design-bid-build.
The scope of work included construction of nearly 1 mile
of new roadway, three new bridges and the replacement of a
traffic rotary with an at-grade intersection. The job also
included more than a mile of pedestrian and bicycle trails,
furthering the vision of a long-anticipated Fore River Trail
that will connect the Fore and Stroudwater River trails to
Portland's Old Port.
The key to the project's success was the ability to start
construction on portions of the project well before design
was finished elsewhere, which would have been impossible under
traditional procurement methods that put a project out to
bid only when the entire design was complete, says Shawn Smith,
project manager with the Maine DOT.
Here, contractors got moving early on an 18-month preload
of the road bed, which consolidated the site's marine clay
in preparation for construction. While the site was compressing,
designs were finalized on other portions of the project and
work was able to start on the new intersection.
Designers and contractors also were able to craft a complex
traffic management plan, one that involved detailed input
and expertise from more than 40 stakeholders.
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The building team sets
steel on Bridge 3, one of three bridges along the Fore
River.
Photo courtesy of Maine DOT |
With all team players working together in the design-build
environment, efficiencies not typically associated with publicly
bid work were realized.
"We were all pushing on each other to get answers,"
says Mark Barnes, project manager with Associated Constructors
of Maine member firm Shaw Bros. Construction, of Gorham, the
job's earthwork subcontractor. "We were able to manage
things much faster and get things accomplished much quicker."
Past Success
Maine DOT became familiar with the design-build method in
2000 with the construction of the Sagadahoc Bridge between
Woolwich and Bath. Its smooth completion and substantial time
savings made the project a success, so when the Maine legislature
later approved design-build for highway construction, the
DOT began its search for a team that could handle the Portland
Connector job.
"Bridges are complex," Smith says. "[The Sagadahoc
Bridge project] proved that the design-build method can be
useful and showed us what a team can come together and do."
The DOT advertised the highway job in August 2002 and in
less than a year had found its team: general contractor Cianbro
Corp., Pittsfield, Maine; earthwork contractor Shaw Bros.
Construction; the Manchester, N.H., office of engineering
firm Louis Berger Group; and geotechnical engineer S.W. Cole
Engineering, Gray, Maine. Work began two months later.
"All the candidates' proposals indicated multiple tasks
going on all the time, but the Cianbro team had a better consistency
to it," Smith says. "Right off the bat, they got
the geotechnical program working."
Extensive Prep Work
The area's clay-rich soil required considerable attention
before work could begin. Crews preloaded portions of the roadway,
adding fill atop the spongy soil. The nearly year-and-a-half-long
exercise squeezed excess water from the soil and compressed
the ground to minimize future settling.
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Crews start construction
of a retaining wall as part of the Portland Connector
project.
Photo courtesy of Maine DOT |
While the future roadway site was compressing, design continued
elsewhere on the project. Crews performed utility relocations
and focused on Veteran's Circle-one of the busiest traffic
rotaries in Maine. A multi-stage plan to demolish the rotary,
remove two flyover bridges and construct a new intersection
was put in place-all while maintaining the flow of more than
20,000 cars through the area each day.
Construction of the project's three bridges followed, finishing
with the roadway connecting the entire project.
A detailed plan to alleviate congestion at the busy Veteran's
Circle was the focus of a half-day planning session held before
work started. Representatives from the city, state, design
and construction team, and surrounding businesses and neighbors
came together to talk about specific needs and potential impacts.
Business owners detailed where and when their deliveries might
be affected by construction, and municipalities shared rush-hour
traffic patterns with the group. This pre-planning discussion
helped form the eventual phasing of work and resulted in a
process that kept traffic moving throughout construction.
"That's one of the things the DOT can't do in the design
phase [under a typical design-bid-build scenario] because
we don't know how the contractor is going to attack a project,"
Smith says. "In this case, because we have the contractor
right there, we can work some of these things through immediately,
months before construction has even started."
"What could have been a massive hemorrhage of traffic
problems turned out to be a smooth-flowing plan," says
Lou Campbell, project manager with Associated Constructors
of Maine member firm Cianbro Corp.
Before road construction started, Shaw Bros. used a satellite
global positioning system to perform the majority of the layout
and grading of the site, cutting surveying time by at least
50% and greatly reducing the possibility of human error, says
John Allen, the firm's grade layout foreman.
Surveyors used Real Time Kinematic GPS to take measurements,
a system relatively new to highway construction applications,
which provided a 95% confidence level within an inch on horizontal
measurements, Allen adds. Maine DOT was so impressed that
it asked Allen to make a presentation detailing Shaw Bros.'
use of the system on construction projects to its surveyors
at a DOT conference.
The use of GPS allows one person to map the site remotely
instead of sending two people into the field with stakes and
survey equipment.
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An aerial view of the
Portland Connector project shows the completed job from
west to east.
Photo by Don Johnson Photography |
"It's a complete 180° change from how things have
been done on DOT projects," Allen says.
Substantial Savings
The general contractor's early involvement in the conceptualization
and design of the Portland Connector helped economize several
aspects of the project, Campbell says.
For example, the ability to offer value-engineering input
resulted in a completely different approach to construction
of the Danforth Street portion of the job than crews had initially
anticipated. Crews expected to remove all the asphalt, curbing
and other components of the existing road before building
the new section. However, it was discovered early on that
the existing roadway was fairly new, enabling the contractor
to reuse curbing and scale back planned excavation and paving
work.
"It represented quite a savings for the people of Maine,"
Campbell says.
In-person collaboration with the stakeholders, neighbors,
owner and builders was vital, says Dale Spaulding, design
project manager and Berger vice president. The design-build
process made that interaction possible, something that wouldn't
have happened in a conventional design-bid-build situation.
"Typically, as designers, we work with design reviewers
at the state agency who never have input from the contractor,"
Spaulding adds. "Eighty percent of the time the contractor
comes on board and wants to do things a different way. Here,
we all came up with a plan that was real instead of working
in a box with a bunch of traffic engineers saying, 'This is
the way it should go.'"
Relationships formed among the design-build team and dozens
of business owners and neighborhood groups during preliminary
studies were strengthened through formal gatherings as well
as informal partnering sessions. The outreach proved to be
more than a good will gesture.
Discussions at one of the meetings resulted in a complete
redesign of truck storage lanes near the Cassidy Point business
district to accommodate the needs of the area's business owners
while creating a more efficient traffic scheme.
"The term 'teamwork' can sometimes sound like a cliché,
but the meaning is true when it's applied wholeheartedly,"
Spaulding says.
The Portland Connector opened to traffic on Nov. 18, 2005.
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