I-5 Between Tacoma and Vancouver(WA)

[Plutonic Panda]

Interstate 5 Mounts Road to Steilacoom-DuPont Road Corridor Improvements Project will begin:

https://www.thenewstribune.com/news/local/traffic/article315739849.html?link_source=ta_first_comment&taid=6a0b7e508d027a0001f7e7f5&utm_campaign=trueanthem&utm_medium=social&utm_source=facebook&fbclid=IwdGRleAR56VBleHRuA2FlbQIxMQBzcnRjBmFwcF9pZAo2NjI4NTY4Mzc5AAEegqxiwsH4dhPoqwKF3Fs7lSG9EKGmVjTH090cs72xnQWlshSe2wrGQHBRkQw_aem_qmyI9No8eXuXV4iyIquufg

Project website: https://wsdot.wa.gov/construction-planning/major-projects/i-5-mounts-road-thorne-lane-ic-corridor-improvements

[stevashe]

Interstate 5 Mounts Road to Steilacoom-DuPont Road Corridor Improvements Project will begin:

https://www.thenewstribune.com/news/local/traffic/article315739849.html?link_source=ta_first_comment&taid=6a0b7e508d027a0001f7e7f5&utm_campaign=trueanthem&utm_medium=social&utm_source=facebook&fbclid=IwdGRleAR56VBleHRuA2FlbQIxMQBzcnRjBmFwcF9pZAo2NjI4NTY4Mzc5AAEegqxiwsH4dhPoqwKF3Fs7lSG9EKGmVjTH090cs72xnQWlshSe2wrGQHBRkQw_aem_qmyI9No8eXuXV4iyIquufg

Project website: https://wsdot.wa.gov/construction-planning/major-projects/i-5-mounts-road-thorne-lane-ic-corridor-improvements

That news article is about some closures happening this month as part of the project, but work actually started in 2023 and it's scheduled to be complete later this year.

This is still a decent time to start this thread though as WSDOT is looking into alternatives to build a new crossing of the Nisqually River and potentially widen I-5 immediately South of that project: https://wsdot.wa.gov/construction-planning/search-projects/i-5-marvin-rd-mounts-rd-planning-and-environmental-linkage-nepa

[Plutonic Panda]

Interstate 5 Mounts Road to Steilacoom-DuPont Road Corridor Improvements Project will begin:

https://www.thenewstribune.com/news/local/traffic/article315739849.html?link_source=ta_first_comment&taid=6a0b7e508d027a0001f7e7f5&utm_campaign=trueanthem&utm_medium=social&utm_source=facebook&fbclid=IwdGRleAR56VBleHRuA2FlbQIxMQBzcnRjBmFwcF9pZAo2NjI4NTY4Mzc5AAEegqxiwsH4dhPoqwKF3Fs7lSG9EKGmVjTH090cs72xnQWlshSe2wrGQHBRkQw_aem_qmyI9No8eXuXV4iyIquufg

Project website: https://wsdot.wa.gov/construction-planning/major-projects/i-5-mounts-road-thorne-lane-ic-corridor-improvements

That news article is about some closures happening this month as part of the project, but work actually started in 2023 and it's scheduled to be complete later this year.

This is still a decent time to start this thread though as WSDOT is looking into alternatives to build a new crossing of the Nisqually River and potentially widen I-5 immediately South of that project: https://wsdot.wa.gov/construction-planning/search-projects/i-5-marvin-rd-mounts-rd-planning-and-environmental-linkage-nepa

Interstate 5 Mounts Road to Steilacoom-DuPont Road Corridor Improvements Project will begin:

https://www.thenewstribune.com/news/local/traffic/article315739849.html?link_source=ta_first_comment&taid=6a0b7e508d027a0001f7e7f5&utm_campaign=trueanthem&utm_medium=social&utm_source=facebook&fbclid=IwdGRleAR56VBleHRuA2FlbQIxMQBzcnRjBmFwcF9pZAo2NjI4NTY4Mzc5AAEegqxiwsH4dhPoqwKF3Fs7lSG9EKGmVjTH090cs72xnQWlshSe2wrGQHBRkQw_aem_qmyI9No8eXuXV4iyIquufg

Project website: https://wsdot.wa.gov/construction-planning/major-projects/i-5-mounts-road-thorne-lane-ic-corridor-improvements

That news article is about some closures happening this month as part of the project, but work actually started in 2023 and it's scheduled to be complete later this year.

This is still a decent time to start this thread though as WSDOT is looking into alternatives to build a new crossing of the Nisqually River and potentially widen I-5 immediately South of that project: https://wsdot.wa.gov/construction-planning/search-projects/i-5-marvin-rd-mounts-rd-planning-and-environmental-linkage-nepa

Thank you for the correction and I'm glad this project is coming along and almost finished. Google Maps is a bit out of date I was looking around the area and I was bit confused.

Also good to hear about the next projects coming to widen the road to three lanes each way. I did the gap where it's only 4 lanes total which is a bit surprising but I figured they were going to get on it soon. Doesn't look like they have much left to widen.

[stevashe]

Interstate 5 Mounts Road to Steilacoom-DuPont Road Corridor Improvements Project will begin:

https://www.thenewstribune.com/news/local/traffic/article315739849.html?link_source=ta_first_comment&taid=6a0b7e508d027a0001f7e7f5&utm_campaign=trueanthem&utm_medium=social&utm_source=facebook&fbclid=IwdGRleAR56VBleHRuA2FlbQIxMQBzcnRjBmFwcF9pZAo2NjI4NTY4Mzc5AAEegqxiwsH4dhPoqwKF3Fs7lSG9EKGmVjTH090cs72xnQWlshSe2wrGQHBRkQw_aem_qmyI9No8eXuXV4iyIquufg

Project website: https://wsdot.wa.gov/construction-planning/major-projects/i-5-mounts-road-thorne-lane-ic-corridor-improvements

That news article is about some closures happening this month as part of the project, but work actually started in 2023 and it's scheduled to be complete later this year.

This is still a decent time to start this thread though as WSDOT is looking into alternatives to build a new crossing of the Nisqually River and potentially widen I-5 immediately South of that project: https://wsdot.wa.gov/construction-planning/search-projects/i-5-marvin-rd-mounts-rd-planning-and-environmental-linkage-nepa

Interstate 5 Mounts Road to Steilacoom-DuPont Road Corridor Improvements Project will begin:

https://www.thenewstribune.com/news/local/traffic/article315739849.html?link_source=ta_first_comment&taid=6a0b7e508d027a0001f7e7f5&utm_campaign=trueanthem&utm_medium=social&utm_source=facebook&fbclid=IwdGRleAR56VBleHRuA2FlbQIxMQBzcnRjBmFwcF9pZAo2NjI4NTY4Mzc5AAEegqxiwsH4dhPoqwKF3Fs7lSG9EKGmVjTH090cs72xnQWlshSe2wrGQHBRkQw_aem_qmyI9No8eXuXV4iyIquufg

Project website: https://wsdot.wa.gov/construction-planning/major-projects/i-5-mounts-road-thorne-lane-ic-corridor-improvements

That news article is about some closures happening this month as part of the project, but work actually started in 2023 and it's scheduled to be complete later this year.

This is still a decent time to start this thread though as WSDOT is looking into alternatives to build a new crossing of the Nisqually River and potentially widen I-5 immediately South of that project: https://wsdot.wa.gov/construction-planning/search-projects/i-5-marvin-rd-mounts-rd-planning-and-environmental-linkage-nepa

Thank you for the correction and I'm glad this project is coming along and almost finished. Google Maps is a bit out of date I was looking around the area and I was bit confused.

Also good to hear about the next projects coming to widen the road to three lanes each way. I did the gap where it's only 4 lanes total which is a bit surprising but I figured they were going to get on it soon. Doesn't look like they have much left to widen.

Tacoma to Olympia is already 6 Lane minimum. This project would add HOV lanes to make it 8.

The 4 lane section you are thinking of is between Olympia and Portland. As far as I know, there is no plan to close that gap completely, but there is a potential project to widen a small portion in Chehalis

[jakeroot]

It appears the wild new Steilacoom-Dupont Road DDI interchange is substantially or totally complete.

In addition to the DDI, this continues WSDOT's improvements to I-5 through the bases. I-5 in this area was previously 6 lanes, it is now 9 after the addition of two HOV lanes (now continuous from Gravelly Lake Drive to here) and a southbound auxiliary lane. The signal at Wilmington & Barksdale was also downgraded to an all-way stop.

Besides roadway improvements, the new bridge also eliminates the prior at-grade railway crossing. This has an additional positive benefit of allowing the entire freeway to be rebuilt flat, so that it no longer has to dip below the old overpass, which created flood issues.

It would not surprise me if this project wins some kind of award. It is genuinely one of the most interesting things I've seen built anywhere in a long time.

Portions of it are on Google Street View: https://maps.app.goo.gl/iiJfeVpAic32vJ7F6

Minor note: the 'yield ahead' pavement marking was painted backwards. Oops.  It was previously painted correctly.

Image from WSDOT's Flickr:


I-5 - Mounts Rd. to Steilacoom-DuPont Rd. - Corridor Improvements by Washington State Dept of Transportation, on Flickr

[stevashe]

That Steilacoom-Dupont Road DDI is in fact substantially complete. The interchange opened on March 22, and the HOV lanes opened in June.

It's definitely an impressive and unique project, but I'm a little sad that I can't use the east side of the interchange without running into the military base's gate...

[jakeroot]

It's definitely an impressive and unique project, but I'm a little sad that I can't use the east side of the interchange without running into the military base's gate...

The east (south?) side of the interchange does have a U-turn option at the traffic light. It's marked as a right turn, and I'm 100% sure it's for traffic that went that way accidentally, not intending to enter the base. It's quite unusual (ie this might be the first) to see this type of turn permitted at a DDI crossover, because there would normally be a conflicting signal from the off-ramp. Luckily that movement is a free-flow slip lane, so traffic can do that U-turn without conflicting with anyone.

Until very recently, before the final paving happened, this was not a permitted movement. But you can see it in the above image (double left turn towards the base gate, with the right lane also having a right-turn arrow).

EDIT: If you do take the time to go out there, and want to wander around as a pedestrian, let me know how the crosswalks work on the south/east side of the interchange. As designed, there would always be conflicting traffic with both crosswalks; the lower crosswalk would require the off-ramp double right turn to have a flashing yellow arrow to allow any kind of movement. Otherwise, everyone gets a red when that is activated. I'm a little confused they didn't design the crosswalk to cross into the much larger island (to the left in the image above), where both crosswalks could active simultaneously with traffic without any conflicts. I guess they don't expect much pedestrian traffic.

[stevashe]

EDIT: If you do take the time to go out there, and want to wander around as a pedestrian, let me know how the crosswalks work on the south/east side of the interchange. As designed, there would always be conflicting traffic with both crosswalks; the lower crosswalk would require the off-ramp double right turn to have a flashing yellow arrow to allow any kind of movement. Otherwise, everyone gets a red when that is activated. I'm a little confused they didn't design the crosswalk to cross into the much larger island (to the left in the image above), where both crosswalks could active simultaneously with traffic without any conflicts. I guess they don't expect much pedestrian traffic.

That is quite strange. I might have to investigate next time I travel south.