Re: San Fran. Bay Bridge Toll Plaza Bypass

I looked at it again this morning. Hoping to nail down a few more
details....

Mark Roberts <[EMAIL PROTECTED]> had written:
| I also tried to take a closer look today, both on the way in and the
| way back home. However, my route is to and from the Oakland side.
| Hopefully we can get some convergence here....
| 
| Andrew Tompkins <[EMAIL PROTECTED]> had written:
|[from the Berkeley side] 

| | The separate carpool lane crosses over and rejoins the mainline 
| | from the right as a
| | single, non-merging lane marked with a diamond,

This appears to be correct.

| | Entrance ramp from I-580 joins the freeway from the left 
| | with 4 lanes (no merging),
| | the left most marked with a diamond,
| 
| The diamond lane actually starts at the foot of the 580 ramp onto 80.
| It actually opens up a new lane at that point.

Confirmed.
| 
| | The I-80 carpool lane (on the right) exits to the right again 
| 
| I looked tonight, and it wasn't clear from my vantage point (which
| is usually the leftmost carpool lane). There *is* an "exit" for a
| carpool and truck lane that, in reality, serves as a bypass around
| the main toll plaza. There's even a bus stop there. But as for
| whether that "exit" is connected with the carpool lane from the
| Berkeley direction -- I'd have to look again from a better vantage
| point.

[perspective westbound]
The right-side carpool lane exits the main road *before* the
on-ramp from I-880 enters the main road. It bends around, so to
speak, to allow the 880 on-ramp to join the main route.

What isn't clear to me is whether the 880 carpool lane joins the
Berkeley-side carpool lane at this point. That wouldn't seem
possible because the 880 carpool lane is the leftmost lane of the
on-ramp.

| | An additional lane exits to the right which does a 180 over 
| | the whole freeway and
| | connects to Grand Ave. (no connection to I-880 SB),
| 
| That's correct.
| | 
| | A lane exits to the left (from the diamond lane from I-580) which 
| | goes to the toll plaza employee parking lot,
| 
| Yes.
| | 
| | NB I-880 passes over the entire freeway,
| | 
| | I-880 joins the freeway along 3 roadways as the freeway spreads out 
| | for the toll plaza; 1 lane joins from the left into the 
| | leftside carpool lane from I-580
| 
| Actually, there are no lanes joining the left carpool lane from the
| Oakland side. So that can't be the present situation.

Confirmed.
| | 3 lanes join from the right
| | (non-merging); and one lane joins the separate I-80 carpool lane 
| from the left
| | (non-merging)
| 
| I think this is correct.

I'm not so sure now. I couldn't tell from my vantage point.
| | 
| | The freeway enters the main toll plaza with 3 lanes bypassing on the right,
| | 
| | The leftmost lane of the 3 bypass lanes spreads to 3 lanes 
| | and enters a secondary
| | toll plaza which is bypassed on the right by the remaining separate 2 lanes
| | (including the I-80 carpool lane),
| 
| I believe only one lane bypasses the smaller toll plaza. Again, my
| perspective today was from the left carpool lane, so it was hard to
| tell.

And I still really couldn't tell today. There is enough width for
two lanes but I couldn't determine if there was an actual usage of
two lanes.

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