Aren't all HOV lanes separated? Any that I've seen in Canada and the eastern US only allow you to merge at dedicated locations. The new ones on the 400 in Canada actually have a merge lane appears for a few hundred metres before shrinking down again, even though there's no physical barrier, it's all just paint.
I don't think that's the kind of separation they're talking about. It's technically illegal to cross that yellow line, but I've never heard of anyone getting in trouble for crossing out and back in to go around a grandpa going 45 in a 70. There are some HOV lanes in Florida that actually split into an entirely separate side road and some that have those soft rollover columns you can drive through but it will scratch up your car so it's really only for emergencies.
Exactly. There is a difference between not allowed to merge and not physically able to merge.
Merging not being allowed is still dangerous because people don't always follow the rules. It might even be more dangerous than lanes that always allow merging because then at least drivers in the faster lane can prepare themselves to expect merging.
A separated lane makes it impossible (or at the very least potentially damaging to the vehicle) to merge.
Here is an example of what I think is the ideal HOV setup[1]. There are two lanes so a single slow driver can be overtaken and there are physical dividers that prevent unexpected merging. You can also see the toll signs mentioned in the article that display the passenger number set on the transponders as discussed in the article.
Yeah that's a pretty good HOV lane in my opinion (as a non city planner lol). Sometimes you still get two slowpokes side-by-side, but it's pretty rare.
No. There are several HOV facilities where it's just a regular lane, especially for 'part-time' HOV facilities (which are basically "this lane is HOV during rush hour, regular otherwise"). For example, HOV lanes on the NJT: https://goo.gl/maps/pKzjvAgFUhac1bva7
Before the changes talked about in this article, the HOV lanes on US101 in NorCal were all "open access". You could enter and exit them at any place you wished, just like any other lane.
That's the case for many other highways with HOV lanes in NorCal as well.
I imagine the main difference is that most of these "open access" HOV lanes are time-limited; outside of the morning and evening weekday rush hours they're not HOV lanes. It makes more sense to have stronger separation for full-time HOV (or toll) lanes.
