Paving Picks Up in Seattle

Story and Photos by Carl Molesworth | September 28, 2010

As a very busy road construction season nears its end in Seattle, city officials are calling 2008 the biggest year yet for improvements made possible by the Bridging the Gap transportation levy.

In all, the city planned to break ground on 338 transportation improvement projects, large and small, with a total estimated cost of $92 million this year. Seattle Department of Transportation crews will build 15 to 18 blocks of new sidewalk and repair many more. Crews also will install new street signs at 1,071 intersections, build 30 new miles of bike lanes and plant 800 street trees.

But the heart of this year's construction program has been four major paving projects.

Work began this spring to pave 15th Avenue from the Ballard Bridge to downtown, making way for bus lanes later this year. The paving project spans 18.6 lane miles and includes stretches of Denny, Western and Elliott avenues. Gary Merlino Construction, Seattle, is the contractor for this $6.6-million job.

The three other major paving projects were:

  • Fifth Avenue through downtown, $2.7 million; contractor Wilder Construction Co., Everett, WA;
  • First Avenue through the SODO area, $3.8 million; contractor ICON Materials Inc., Kent, WA;
  • Boren Avenue and East Madison Street on First Hill, $3.9 million; contractor C.A. Carey Corp., Issaquah, WA.

These four roadways were selected for paving this year so that critical streets will be ready when Alaskan Way Viaduct construction work begins, according to an SDOT press release. All four paving projects, totaling 41 lane miles, were expected to conclude in late fall. The projects will feature bike-friendly grates, bike-sensitive traffic detector loops and pedestrian upgrades. Last year, the city paved 27 miles of roadway. The city used to pave between four and eight miles a year, the release added.

“These transportation projects will get Seattle moving,” Mayor Greg Nickels said in April. “This year, we are shifting into high gear to create a transportation system that makes it safer and easier to bike, bus, walk, and drive.”

Competitive Bids

Putting the major paving projects out to bid in early 2008 helped SDOT avoid problems with rising asphalt prices and uncertain availability that have been reported in other parts of the Northwest recently.

“This year we benefited from bidding early in the year,” said Jessica N. Murphy, P.E., the SDOT project manager in charge of the paving program. “We got competitive bids. The price curve stayed pretty even with last year. We're paying $90 to $100 per ton (for asphalt).”

When PB&E visited the Boren Avenue project on a Saturday morning in late August, a crew from Lakeside Industries was finishing up an overnight paving session between Denny Way and Seneca Street. A lot of work had been done on the roadway before any asphalt went down.

“First we identify areas of pavement failure and repair them,” Murphy said. The next step is to grind two inches off the existing pavement, look for more failures and fix them as well. After the crew handles the cut-ins, the roadway is ready to pave.

“This minimizes the time that the ground surface is exposed,” Murphy explained. Otherwise, traffic running over the exposed areas beats them up more and causes further failures.

SDOT specifies 1/2-inch hot mix asphalt for the overlay, but each paving contractor submits its own mix design for approval by the city. The mix standards are very similar to those used by the Washington State Department of Transportation, she added.

The city's smoothness requirement allows for 1/8-inch variation on a 10-foot straight edge longitudinally, and 1/4-inch on a 10-foot straight edge for the transverse slope.

Downtown Work Next Year

Murphy said she is keeping a close eye an asphalt prices, because they have a direct effect on the amount of paving the city will be able do next year.

“The dollar in construction doesn't go nearly as far as it used to,” she observed. “We're having a hard time even estimating project costs, due to the volatility of the market. If prices go up, we may have to push projects back to the following year.”

But the city keeps designing projects at the same rate, so that if prices go down there will be projects ready to go.

SDOT's paving program for 2009 will include a lot of work in the downtown area, with significant partial and full reconstructions, Murphy said. She mentioned the following four projects:

  • Partial reconstruction on Stewart Street, with half of the roadway paved in full-depth concrete where it is subject to heavy bus traffic;
  • A combination of reconstruction and mill/overlay on 2nd and 4th avenues in the Belltown area;
  • Full reconstruction in concrete on Pike Street between 1st and 2nd avenues;
  • Full asphalt reconstruction, with drainage and water main replacements, on 1st Avenue South, which will cost $8 million to $10 million.

Also in design is work on Fauntleroy Way in West Seattle, which SDOT hopes to build next year, Murphy said.

Approved by voters in 2006, the $365-million Bridging the Gap levy enables much-needed work by SDOT, such as roadway paving, sidewalk development and repair, bridge upkeep, and tree pruning and planting. It also supports the Bicycle and Pedestrian Master Plans, the Safe Routes to School program, enhanced transit connections, and large Neighborhood Street Fund projects.