By Sarah Hannon-Nein
Great news for the saga of I-5 pavement replacement in Clark County! The infamous southbound I-5 pavement between 179th Street and the I-5/I-205 split has been a rough ride for a long time—but after a recent project, and more planned in the years ahead, we have updates about the highway that just keep on giving – or, in this case, cracking.
Aged-out I-5 pavement in Clark County
If you live in or travel through Clark County, you’re probably familiar with the bumpy surface between Ridgefield and the I-5/I-205 split. We put up Rough Road signs earlier this year. This stretch of highway includes 8,400 concrete panels which are 50 to 70 years old and past due for replacement, and well beyond their expected lifespan.
These panels, which carry some of the highest traffic volumes in the state, are worn out, cracked and need repair or replacement. Working on thousands of panels takes time and money, so we're using multiple contracts over multiple years. With increased traffic and extreme weather, the panels fail faster each year, and we don't have enough funding to fix them as quickly as they are failing. With only about 40% of the funding needed to maintain our highway system, we have to make hard choices about what we can fix and when.
The good news!
WSDOT contractor crews spent this fall putting $2.3 million to use to address the “worst of the worst” panels and, by taking advantage of favorable materials cost, took care of over 80 panels instead of the 40-45 previously planned. Will you still notice a bumpy ride? Yes. But the panels in the roughest shape have been replaced! It’s a small, but important improvement.
Our next project is slotted for 2026 and while it will be a big challenge, it will bring a long-term solution for a smoother and safer drive. We'll also be doing something new in this stretch of highway to reduce traffic delays and keep costs low so we can fix more of the problem sooner.
Enter the crack, seat and overlay process.
In summer 2026, all southbound lanes and shoulders between 179th Street and the I-5/I-205 split will be paved with asphalt over the existing concrete panels. This marks a major step for this troubled section of I-5.
So why are we using asphalt instead of replacing all those concrete panels? Replacing every panel would be a never-ending project with a very high cost, meaning it would take more contracts and more years to complete as funding became available.
Here’s how the crack, seat and overlay process will work:
Crack: We start by cracking the old concrete panels. This is done using a machine that essentially breaks the concrete into smaller pieces. It looks like a small guillotine dropping a heavy weight onto the panels every few feet.
Seat: Once cracked, a large 35,000-pound steel compactor on wheels rolls over the broken pieces, pressing them down to make sure they’re firmly seated into the ground.
Overlay: We lay down a few inches of new asphalt, building it up gradually until we reach 9 inches. This slow layering is important to ensure the new overlay is packed in tightly, creating a smooth and durable driving surface.
This process will take time and every bit of dry weather we can get. Hopefully if funding can be identified in 2027, the work will continue between Ridgefield and 179th Street.
This isn’t a quick fix, and we’re looking at more years of work to finish repairing this stretch of I-5. Until then, you’ll still see Rough Road signs as we continue to do this work. We’re making progress–one crack at a time. Thank you for your patience while we work on this major improvement for Southwest Washington!