With the success the Washington State Department of Transportation is saying it is having with the new express toll lanes on I-405, it begs the question: how long will it be before the state decides to add them to I-5?

Travel times in the general purpose lanes have decreased on I-405, according to data from WSDOT. In some cases the trip is 10 to 20 minutes faster. The toll lanes are running around 15 minutes faster than the general purpose lanes for a toll under an average of $2.

In the next few years, the state will extend those toll lanes all the way south from Bellevue to Tukwila to join the HOT lanes on SR 167.

“Eventually, give us a 40-mile express lane system all the way from the Sumner Auburn area down in Pierce County, all the way through Renton to Bellevue, up to Lynnwood…” tolling director Craig Stone explained.

But that would leave I-5 and I-90 as the only freeways in the region without tolls. How long before those routes get their own tolls?

“There is a longer range plan … that you would think about the HOV lanes and what there should be and how they should operate … but at this point in time there’s no strategies being put in place,” Stone explained. “No action by the Legislature or the department to put that into place.”

But tolling I-5 is in the consideration pile for the future as a way to manage the congestion. It might be way off, but it’s in the discussion.

What about the possibility of changing the HOV requirement on I-5, making it three-plus?

Stone says just making that move will not improve congestion. It would simply move people into the general purpose lanes and make things worse. That’s why the three-plus change on I-405 came with the addition of the toll lanes.

So drivers should not expect that change on I-5 by itself.

“No, there’s not an action at this point,” Stone said. “But I do think you need to learn from this from the standpoint of how do we take a facility that is not operating well (I-405) and what are the strategies that we can put in place. And this is demonstrating that we can return reliability back.”

You might not realize that portions of SR 520 are three-plus right now, and the original HOV lanes on I-5 were also three-plus before being bumped down to two-plus.