Clark College is quite near I-5, but I have not used I-5 bridge as a bike route., The most problematic issue (besides safety, being only separated from cars by a railing...) is crossing the slough bridge (which is between Hayden Island and Portland (Delta Park)). I think the bridge approaches might be time consuming on I-5, but it could be good to find a spot on Hayden Island to live and then you just have to negotiate the interstate bridge, Once in Vancouver, If you can use the new pedestrian bridge over SR14 (near pedestrian walkway of I-5 bridge) you would be real quick to Clark, with no traffic hassles on Vancouver side.
The I-205 route is nice, but steep, high winds, and long. Once in Vancouver, you can bike McLoughlin (wide, light traffic) if you can climb the hill at Ellsworth. Evergreen Blvd is a flatter route in from the east, but narrow in spots. Portland has a decent bike trail along I-205, but its not the most friendly for commuting, as bike path designers don't think 'timely commute', and their crossings of major roads often result in delays. The 205 bike route is pretty optimal and well used.
BTW - why would you live in OR and school in WA? Kind of an expensive option. Especially if you are working and paying income tax.... you might as well utilize those well fed Portland colleges that you are paying for. Clark is considered superior in some subjects, especially math, but decent EDU programs in north Portland (Both public and Private).
Good luck,
I would ride both routes, and also blog onto some PDX biking sites, I turned from an avid (Daily) cyclist to a very infrequent rider
when I moved to PNW from Colorado 28 yrs ago. Dark, wet, narrow roads, + very inconsiderate drivers who are not used to '
SEEING
' cyclists. If you appreciate drivers giving you space, you will not be pleased with motorists in PNW. I have found only 10% will give you the courtesy of a couple feet, even if there are no cars approaching or next to them. Plus there are no 'snow' shoulders on the country roads on the west side of Cascades.
Wear bright colors, blinking lights, a side mounted flag, a helmet, and expect to be clipped.
Be careful, lots of folks can tolerate the danger of bike commuting in PNW, but since I gained the 'responsibility' of being a parent the same time as my move here... the bike commute had to go, and the life insurance had to increase. (yet another sacrifice from the 'freedom' of single-hood...
). Colo was heaven for cyclists, especially Boulder where they had full use of the right lane, and cars that don't move over got ticketed
I didn't live near there, but enjoyed riding through. We did 40-50 mile rides 2x / week on the way to work, and swam 72 laps on the other 3, I WAS in great shape, then
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Bussing and bikeing from Portland to Vancouver
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