Washington State Department of Transportation blog post written by Stafanie Randolph and Jamison Murphy.
Did you know that Washington is the true home of fish and chips? If you travel on state highways this summer, there is a good chance you will come across a fish passage barrier removal or chip seal project. Like crispy fried fish and chips, both types of projects are better when it’s hot. We talk more about fish barrier removal in other blog posts so let’s focus here on chip seal. You’ll keep seeing these projects on our roads through the end of summer, and then they’ll be back again next year. Here’s why you see these projects during popular travel months, and what it means for how you drive.
What is chip seal and why is it important?
These chips aren’t delicious, but they do make our road surfaces a little more fresh. Chip seal applies a special protective surface to existing pavement. Basically, we lay down a sticky surface on the road and cover it with small chips of rock. Not only does it preserve road surfaces, it even improves traveler safety. The protective coat restores traction to prevent skidding, particularly on wet roads. It maximizes visibility by providing an anti-glare surface during wet weather and an increased reflective surface for night travel.
While my doctor advises against chips every day, it turns out that chip seal is great for roadways. It minimizes wear from aging by making the road more durable and preventing water from penetrating the road. Without chip seal, we would see more potholes during the winter.
Chip seal is the best way to preserve roadways and extend their lifespans. It’s very effective and low cost – 15 to 20 percent of the cost of pavement overlays. We use chip seal to make the most out of our maintenance and preservation budgets.
What does this mean for travelers?
Unlike a basket of fried food, chip seal work takes some time. Crews must shut down lanes to perform the work. Typically, only one lane will be available for traffic in both directions, which means one side of the highway is let through the zone at a time. This traffic flow is guided by a pilot car and flaggers who will lead you through the zone in a manner safe for travelers and the crew.
The speed limit is typically reduced to 35 mph around the clock until a project is complete. The slower travel is not only safer for the people working on the road, it reduces the chance of damage to vehicles. Expect delays of at least 15 minutes, go slow and travel really early or late if you can.
Keep an eye out for loose chips of gravel on the road until the end of the project. Rollers start to embed them in the chip seal oil that will hold them place. Even with the high-pressure rolling, some gravel will not become embedded in the asphalt. Your tires will help to move the rocks around and fill the small gaps in the new surface. Make sure you drive slowly to keep the aggregate on the ground until it can be swept off the road.
Why do we chip seal during popular travel times?
You know how sometimes your fries come out a little soggy, or not cooked all the way through? That’s because the temperature wasn’t just right. We must chip seal within certain moisture and temperature ranges, too. It has to happen during the day and during the time of year we have the least rain. So if the weather’s nice, we’re probably somewhere taking advantage of the weather window and laying down a brand new chip seal on a highway.
We’re mindful of inconveniences caused by delays, and we hope travelers will consider the long-term benefits of protecting the roads for smoother travel and longer lifespan. Until the work is complete, you can help prevent delays by traveling early in the areas we’re doing chip seal, using alternate routes and consolidating trips. You can check for work on your route to the nearest fish and chips stand with our Real Time Travel Map.
Read the original story and see the photos on the WSDOT Blog page here.