It is not just the alleged mayor of our city and his co-conspirator who want tracks all over town:
http://wweek.com/editorial/3345/9589/

So, if we do the math in reverse, that means a traffic-only bridge should only cost about 25% of the advertised price? I'm for that option.

A cross-section I saw showed two vehicle lanes (one in each direction) and four bike lanes. That'll go over big.

Did someone mention bikes, Allen L.? Here's a metaphor in need of blocking:
http://blogs.wweek.com/news/2009/11/02/bikes-viagra-for-the-urban-landscape/

The cross-section shows less than 1/3 of bridge's width is for vehicles and over 2/3rds for peds/bikes. But only about 5% of Portland's population bikes and walks for all trips combined. Sure makes sense here in Portland-huh?

Wouldn't it make more sense to have two 10 ft sidewalks shared between bikes and peds like the Hawthorne Bridge. Thus we would have separated bikeways separated from traffic that the bike lobbyists and planners say is the optimum. Plus, the reduced bridge size from 76 ft to 40 ft-42 ft would get the bridge price down to maybe $180 Million from the now projected $320 Million-back to where it was suppose to be.

Too simple.

Then, take the $200 Million that Sam is trying to steal from the state and feds for the so-called Bio Science Research Building in OHSU's failed SoWhat campus, and apply all or some to this bridge. Now that would be economic development.

There has to be some way to sue or something to stop this insanity. Spend however many hundreds of millions to rebuild a bridge, so that it has LESS capacity? Or rebuild the Columbia crossing for billions with the same number of lanes?

I am awestruck every day at how stupid so many people really are in this town.

I know a bridge we need. A bridge over the gap between how smart Portland do-gooders think they are, and how smart they really are. Can you make a bridge that long?

The cross-section shows less than 1/3 of bridge's width is for vehicles and over 2/3rds for peds/bikes.

Maybe, but if you look at how bridges are constructed, bicycle and pedestrian pedestrian pathways tend to be extended off the sides of the supports, while vehicular traffic passes over the tops of the bridge supports. That's because 150lb. people walking and running, and speeding bicyclist/bicycle combos weighing a couple hundred pounds don't produce as much stress on a bridge as a 100,000lb. MAX train, an 80,000lb. semi, or even a 2000lb. Smart car doing 40mph.

Snards, the problem with putting more than two lanes on the Sellwood Bridge is that the road leading east from the bridge, Tacoma Avenue, has only two lanes, and with 60 feet of right of way could only have four lanes if the entire street consisted of four traffic lanes (x 12 feet = 48 feet) plus two six-foot sidewalks (the current sidewalks are wider). No parking lanes. No bicycle lanes. In other words, something similar to West Burnside between the Park Blocks and 23rd street. I suppose the city could condemn land on either side of the street to make it wider, but that might be pretty costly too, don't you think?

lw, by your logic, since only 5% of our traffic is pedestrian and bicyclists (I think it's a little higher, but let's accept your numbers), then a 50 foot wide bridge section should have one 2.5 foot wide space for both bicyclists and pedestrians.

In other words, worse than the existing bridge.

Gordon, like I wrote, I used the 5% ratio to show the absurdity of what PDOT is advocating in the 1/3 to 2/3 ratio. I used logic and common sense in proposing two 10 ft ped/bike sidewalks. You missed the logic.

The problem with a combined 10-foot lane, lw, can be seen on the Hawthorne Bridge (and which I have seen both on a bike and on foot) - bike/ped conflicts, while not as deadly as bike/car and ped/car conflicts, still occur regularly.

If you wanted to limit bike/peds to 20 feet, you would be better off with 5-foot bike lanes on either side and one 10-foot ped lane on one side.

I bike and walk both bridges somewhat regularly. I would say that for 99% of the time the sharing works fine on the Hawthorne.

If bridge costs need to be reduced and common sense employed then I think having a raised curb protecting both peds and bikes on a crowded vehicle bridge makes better sense than splitting things up then having the cross-over problems of the two different uses at each end of the bridge. That conflict would probably cause more accidents than the few times of crowding on the two shared sidewalks.

Also, having bikeways right next to vehicle traffic with two 5ft paths with no curb or other separation is dangerous-especially on a bridge. Drivers tend to crowd the outside of their lanes, right into the bike lanes. The biker has no where to go but hit the curb and crash and worse.

@gordon: The west part of Tacoma Street used to have more lanes, but several years ago the city took them out and cut the street down to two lanes. The bridge itself has two lanes instead of four because the Burnside Bridge (completed the next year) turned out to cost far more than planned, and the county needed to save a few bucks.