Friday, May 12, 2017

Planning I-5 construction work around Seattle’s busy schedule

by Marqise Allen

Somewhere between zero and one.

That’s the average number of weekends in June, July and August where there isn’t a game, concert or some event happening in the Seattle area. These warmer and drier months also happen to be primetime for highway construction. So how do our traffic engineers plan projects given the near impossibility of an open weekend in the summer, while still trying not to affect drivers too badly?

“A line from the movie ‘Argo’ comes to mind,” said Mike Swires, one of our traffic engineers. “It’s about picking the best bad plan.”
A major part of the northbound I-5 rehab project from Kent to Seattle is replacing aged concrete panels.
Indeed, it takes months of working with project staff to figure out how to fit all the needed work in while also avoiding major events like Seafair weekend, Independence Day weekend and the Bite of Seattle. Keeping as many highway lanes open as possible during those huge events is important, but it starts to cut in on viable work time.

One of the biggest projects in the Seattle area this summer will be #ReviveI5. The northbound I-5 pavement preservation project between Kent and Seattle will require 10 weekends of lane closures, eight of those this year. These weekends are necessary because some of the work, like replacing expansion joints, simply can’t be done overnight. Two hours on the front end and back end to set up and take down the traffic control and heavy equipment would leave only a few hours to do the job and would also extend the timeline and raise the cost of the project significantly.

Getting creative

Crews will replace old expansion
 joints on northbound I-5

between Kent and Seattle.
I-5 has lasted 51 years, but it’s time to give the highway some much needed work. As significant as the actual repaving and panel replacement is, scheduling this critical preservation work is equally important. When we schedule weekends, where drivers are traveling for particular events, other projects as far away as Tacoma, and local city and county projects are happening at the same time all have to be taken into consideration. We all want to take advantage of the few drier months of the year but we can’t all work at the same time.

It’s akin to trying to fit a bunch of puzzle pieces together – accounting for all the variables to put everything together to avoid conflicts between projects, as well as schedule closures so that the effects to events are kept to a minimum. And the infamous Washington weather is a major variable that is out of our control. The schedule is tight enough, but pushing work back due to rain, forces those closures up against bigger event weekends at times.

“We try to think outside the box as much as we can,” Swires said.

What’s the best way to complete the work? Do we close one direction of I-5 completely one weekend to cut down on the total number of weekend closures? Do we close a ramp here or there? What about partnering with the city and detouring traffic through surface streets? Could they handle the 100,000 vehicles that use this section of I-5 each day?

These are all challenging questions to address and the population boom in the area hasn’t made the task any easier. While we try to keep our closures outside of heavier travel times, with as much growth as our area has seen, road work will always impact someone.
Planning major summer roadwork around big events like the Bite of Seattle is a huge challenge.
 (Photo courtesy of Bite of Seattle).
Team effort
Drivers have a part to play in these closures too. Engineers do their best to dodge a minefield of events, but travelers need to know before you go. They can ease congestion during the busy construction weekends by carpooling, using alternate routes and planning their trips accordingly. By planning ahead and knowing what’s going on on the highways, we can all get the most out of a busy and fun summer.

This is the last in a four-part series on highway preservation work starting this month on northbound I-5 from Kent to Seattle. The others are: