STP: alternative to Hwy 30 in Oregon
 

I'll probably ride back to Seattle this year after the ride and google-mapped a route on the other side of the river to avoid hwy 30 between Portland and Longview. I'm not familiar with that area. Can anyone critique this route and tell me if it "goes" or not? Thanks!

https://www.google.com/maps?saddr=Po...&z=12&lci=bike

Having done STP 5 or 6 times myself, long ago in the eighties, I just can't imagine getting back on the bike to ride back. I guess it depends on how long you're staying in Portland.

As far as the route goes, I have no idea. Look where I live right now.

IMO your best bet would be to call one of the numbers LBS in the area for advice. My gut feeling however is that the STP management has planned for the best route already which as you know goes through Saint Helens, OR. Before I 5 was build there was a two land road that was quite nice, I believe it is highway 99, if it still exists in full that maybe ok to follow.

try using street view to look at it. Some points look OK with a shoulder, others look narrow. I didn't see any traffic in street view outside of Vancouver, but I only checked 3 places.

If it were me I'd do it. your route goes through a mostly rural area that is close to a major freeway. My experience is that roads like that are low traffic. Keep in mind I've not even driven the route you propose. Many of my best rides were "discovered" the same way you are choosing your proposed route.

The new Strava Heatmap shows where riders that posted their rides to Strava have ridden. (Blue lines, shaded to red for the most often traveled roads.)
Here's the Strava heatmap map zoomed in.

Some of the roads in blue or red are just the most convenient way (or the only way!) to get to another area, not necessarily the nicest bike rides. But at least, they are bikeable.

See if your proposed route is in blue or red on the map, and you'll know riders have done that route.

I live in and ride around the Portland area, both sides of the river. The route you mapped while doable is not one that I'd ride, especially on a weekday. The roads you've mapped are very narrow, lots and lots of tight curves as well as up and downs. None of that is bad in and of itself, however, they are also roads that see little to no bike traffic, for a reason. Drivers are not "kind" up that way because they don't expect to fly around a curve and there's a bike. The farther east of I-5 you go is where you find excellent cycling roads but the trouble with that is small "bumps" like Mt St Helens being in the way. If I "had" to ride back to Seattle I'd use Hwy 30 as my first option. Wide breakdown lanes to ride in and lots of bicycling usage which means the "locals" aren't surprised.
Hwy 30 is certainly not the prettiest route but in my mind it is the safest.

Thanks! I hadn't known about Strava heat maps. That's really handy.

My thinking is to avoid hwy 30 and reconnect with the STP route in the Kelso area. In all likelihood, I'll take hwy 30 but thought I'd look around. The east side of I-5 is definitely hillier! I have some vague recollection of a fatality along hwy 30 on Sunday morning of Stp a few years ago. I'm also not crazy about the Longview bridge.

One year, I did ride back through Vancouver and Battle Ground, up to St Helens and MRNP but that was a multi-day trip.

I've actually ridden the route that's been proposed--twice! And I don't share KRhea's dire opinion on it. It's not perfect, I will admit, but it's not horrible at the same time. Would I do it again? Yes. Here are my thoughts/notes:

Hope this helps!