Raisedeyebrows said:
now if they'd just start building some bike lanes with concrete barriers to actually protect cyclists from distracted drivers I'll be jumping up and down.
I wish I could say I think those barriers are a good idea, but they come with a bunch of problems in addition to the "protection" they offer. A few thoughts, that don't cover all the problems, below.
Some of this is based on what I see with construction barriers, which sometimes temporarily separate bike lanes and/or sidewalks and/or other areas from traffic lanes. Some of it is based on certain intersections, like some freeway crossings around here, where they have put protection barriers up so that pedestrians are protected from cars that collide with each other and skid and can otherwise impact/crush pedestrians standing and waiting to cross at a corner. (and to protect pedestrians from drivers taking the corners too sharply and running over those standing at the corner on the sidewalk, but that's a rarer thing than the collisions).
At those intersections, before the barriers were installed, pedestrians used to be easy to see, and drivers would generally slow a bit if one was standing there, and even stop to let them cross. Now, pedestrians are lucky to be able to cross even when they have a walk signal, as the drivers don't slow as much (or at all) and don't look for pedestrians much (if at all) even if they are already outside the barrier and starting to cross.
One problem with barriered lanes is that when you're riding to go somewhere, and you have to get out of the barrier area and into / across lanes of traffic to get to your destination (or to get on a different road), you first have to wait till you get to a gap in it, and if those are poorly placed, then you can end up "suddenly" in traffic (as far as the drivers on the other side of it are concerned). It's not really suddenly, but if the drivers are expecting bikes to now always be on the other side of the barrier, then when you have to ride on "their" side of the barrier, the hostility some drivers already feel would increase at these times (vs the way it was before the barriers were installed and they were already used to sharing the road).
If the gaps in the barriers are not frequent (like say, only at intersections), then a cyclist that needs to get to the other side of the street has to either go much further down than they want, then cross the street, then go back the other way to get where they're going. Or they have to exit the barrier at the previous intersection, and now they're trapped in the traffic lanes until they get to their destination.
This means that for those riders that have to be on the "car" side of them (because they can't get where they're going on the "bike" side), they now have nowhere at all to go when a driver does something that they could otherwise have escaped from--they'll be pinned against the barrier, or have to "escape" into a different traffic lane where some other driver could be surprised by them.
A further issue with having nowhere to go is when a pedestrian just steps right off the curb in front of you, and you might've been able to dodge them if the barrier weren't there. But now your choices are to hit them, or to crash into the barrier, or to attempt to ride up the curb and maybe hit some other pedestrian that hasnt' stepped off the sidewalk.
On most of the streets where traffic is really a problem, there's also lots of driveways. This means there would have to be frequent breaks in the barrier, which is good for the cyclists that need to get to the other side of the street (by changing lanes like any other traffic), but bad for the cyclists that are staying in the protected area. With driveways, and barriers like that, drivers that need out of the driveways are likely to pull out all teh way across the protected lane, blocking it, so that they can "see around" the barrier (even if it is very low, they'll still do it--this is what happens with construction barriers on road-edge repair around here). There are places here where traffic out of driveways is fairly constant, and without the barriers, the drivers stop at the edge of the sidewalk (most of the time) so a cyclist could keep riding past...but probably not able to if the barrier were there.
Also, drivers that are going to enter the driveway will suddenly just turn into it, and probably pay even less attention to the cyclists than they did before, because they're protected by the barrier, right? So all the cyclists have to do is stop, right? Meaning every cyclist will have to stop at every driveway if there's traffic that might turn into the driveway. While that can also be true of unprotected bike lanes, the riders will probably have to watch traffic even more than they did without the barriers, because now the traffic doesn't have to watch for them anymore. (not really true, but it'll be the perception)
So while they might keep some collisions from happening, they could actually cause others that wouldn't have happened without them.
Another problem with such barriers is that there's only so much space on a road, and the barriers themselves take up space too. Since it's unlikely space would be taken from the car lanes, the bike lane will be narrowed by the width of the barrier, at least. Some of the areas around here that are striped as bike lanes are already narrower than the handlebars of a typical bicycle, so on those a barrier that stands above, at, or near the height of handlebars would force the rider over into the gutter area (or into parked cars where the bike lane is trapped between traffic and a parking area, also common around here, and problematic in itself for obvious reasons). When in the gutter area, now the handlebars stick out over the sidewalk, so for areas where pedestrians use these there's risk of collision with them, or of idiots reaching out and pushing cyclists into the barriers, etc. (that particular problem happens even without the barriers, but at least a cyclist has somewhere to go then).
Cyclists will be unable to pass each other, except by either riding on the sidewalk, if there's no pedestrians and its' allowed in that area, or by exiting the barrier into traffic, until they can get back into the protected area however far down the road the next break is, assuming there's no other cyclists there at the time; if there are then the one reentering either has to stop and wait, with cars zipping by, or they ahve to ride to the next break, or the next, and so on. So now all bike traffic will happen at the speed of the slowest rider. Makes commuting impractical at that point.
When the inevitable wrong-way-cyclist comes down the lane, more chaos will ensue, since riders can't just go around each other anymore.
If they're wide enough for the above stuff to not be a problem, then they'll also be wide enough for cars to go down them, and that's going to happen, probably even if bollards are put in place.
In narrow places, many trikes and trailers will be unable to fit, unless the rightside wheel is up on the sidewalk, and that would probably mean riding at a walking pace to avoid either tipping over or falling off wherever the curb height suddenly changes (driveways, etc). (I'm not even talking about stuff like I build--just the commercial pedal-only stuff is too wide to fit inside some bike lanes, and sometimes bollards on paths are too close together to fit thru either).
There's also nowhere to go when the street drains and such are so wide and deep that riding thru them is outright dangerous, or even impossible.
One plus would be that as long as they repair the road before installing the barriers, a lot of the road damage that makes riding at the edge of the road unsafe wouldn't recur (from large vehicles braking and accelerating, causing pavement to migrate into hills and valleys like waves). Unfortunately I don't imagine they'd do the repairs first, and after they isntall the barriers, the machinery to do the repairs couldn't get in there to be able to fix them afterward.
Also, barriered areas collect more trash, debris, and other junk that can cause flats, etc. Streetsweepers cannot get into the barriered areas, so they are never cleaned except by rain/wind during the very infrequent storms. If the areas are made wide enough for sweepers, they're also wide enough for the rest of traffic, and there *will* be drivers that use them as an extra lane, and all the chaos and potential injuries and fatalities that will ensue from that.
Also, very infrequently, the freeway intersection areas get used as dumping grounds for large piles of trashbags and yard waste, completely blocking their use by pedestrians/etc. That doesn't seem to happen in the construction zones, but I expect it would with barriered bike lanes.
