Redesign This: I-12 Westbound into I-10

[jbnv]

It looks like the original Redesign This thread has run its course, so I'll make a new specific thread instead of rebooting it.

Here's the situation heading westbound through the I-12 terminus towards downtown Baton Rouge:

Ahead of the terminus, the guide sign indicates "I-10 WEST Baton Rouge" even though you've already been in Baton Rouge for several minutes. It would make more sense for it to say "Downtown / Lafayette."

At the terminus, you're still approaching "Baton Rouge." Here's what's going to happen to the three lanes that are going from I-12 into I-10 westbound:

* The rightmost lane is going to exit-only onto College Dr.

* The center lane is going to exit-only onto Acadian Thruway about 2.5 miles ahead.

* The leftmost lane (the only lane of these that's actually going to downtown and Lafayette) is going to become the rightmost lane on I-10 west once the rightmost lanes peel off at their respective exits. Up ahead, people will be weaving leftward from the rightmost lanes as soon as they discover that those lanes are exiting only. They'll cross paths with I-10 traffic weaving rightward to get to the College and Acadian exists. This is a lot of fun during rush hour.

Here's your first indication that the rightmost lane is exiting only. Keep in mind that the center lane is going to exit only ahead and that the leftmost lane, which you need to be in to go to downtown or Lafayette, may be congested in fairly short order.

As I-12 ends, there is no indication that, depending on where you are going, you need to be...

* If you are going to Lafayette, in lanes 1 or 2.

* If you are going downtown or northbound via I-110 (which hasn't received any mention yet and won't for a few more miles), you need to be in lanes 2 or 3.

* If you are not exiting at College or Acadian and you are in lanes 4 or 5, you need to prepare to move to lane 3.

(Take this GMSV and imagine the lanes from I-10 are filled, and the leftmost lane from I-12 is filling up with people preparing for the rightmost lanes to split. That's what it looks like every evening during rush hour.)

It is not until the College Drive exit that you finally get warning that lane 4 is about to exit only. Notice in the May 2017 GMSV that traffic is already backed up in the Acadian Thwy exit-only lane. There surely are people in that queue that are trying to get over to the third lane to stay on I-10.

Notice also the reassurance marker. No mention of I-110 or downtown.

Your job, should you choose to accept it, is to create guide signs and other indicators to:

* Direct traffic coming from I-12 and proceeding through to downtown or to Lafayette into the leftmost lanes.

* Direct traffic bound for Lafayette into lanes 1 and 2 and bound for downtown into lanes 2 and 3.

* Alert these motorists of congestion through the stretch between I-12 and I-10.

* Alert motorists coming from I-10 to exercise caution if attempting to exit at College Dr. or Acadian Thwy. They will have to weave across two lanes to get to College and one for Acadian--lanes potentially containing high-speed traffic coming from I-12 attempting to merge left to stay on I-10.

* Alert motorists coming from I-12 of traffic crossing their path to get to the College or Acadian exits.

[NE2]

Ahead of the terminus, the guide sign indicates "I-10 WEST Baton Rouge" even though you've already been in Baton Rouge for several minutes.

Too fucking bad. Cities annex suburbia.

[Flint1979]

The signs for SB I-75 on 8 Mile Road in Detroit say Detroit even though your on the border of Detroit. South of there is where the signs start saying Toledo instead.

[Anthony_JK]

Fortunately, there are some plans afoot to relieve this situation.

First, the additional through lane in each direction planned for all of I-10 between the 10/12 and 10/110 Splits will certainly relieve the congestion overall.

Secondly, LADOTD has developed a plan for a dedicated ramp for traffic on I-10 westbound to Acadian Thruway which would begin before the 10/12 Split, cross over I-12, and then merge with the existing exit to Acadian from I-10. This would remove the need for traffic from I-10 westbound south of the 10/12 Split to merge across I-12 West traffic to reach the existing Acadian exit; leaving the latter for traffic from I-12 west.

As for signage....the main problem with putting "Downtown" reassurance signs on I-10 is that it doesn't quite reach downtown; it turns westward at the 10/110 Split to head over the river and towards Lafayette. That issue could be solved by placing "WEST I-10/TO I-110 NORTH; Downtown Baton Rouge/Lafayette" at the end of I-12 West (with the rightmost lane signed for the Acadian Thruway exit).

I'll defer to the pro sign makers for the prototypes. Just slinging ides.

[jbnv]

The plans involving construction aren't going to be implemented for several years. The signage could be resolved fairly shortly and

Secondly, LADOTD has developed a plan for a dedicated ramp for traffic on I-10 westbound to Acadian Thruway which would begin before the 10/12 Split, cross over I-12, and then merge with the existing exit to Acadian from I-10. This would remove the need for traffic from I-10 westbound south of the 10/12 Split to merge across I-12 West traffic to reach the existing Acadian exit; leaving the latter for traffic from I-12 west.

That's going to be a darn long ramp. Aside from the fact that this isn't Texas, where putting a long ramp over everything in its path is no big deal, how exactly is this thing going through the strip of hotels, restaurants and Gordon McKernan between I-12 and College? I don't see it happening, even if McKernan lets it.

As for signage....the main problem with putting "Downtown" reassurance signs on I-10 is that it doesn't quite reach downtown; it turns westward at the 10/110 Split to head over the river and towards Lafayette.

That doesn't seem to matter on the west side of the expressway:



I-12 doesn't even exist at this point, and DOTD managed to put I-12 ahead of I-10. I see no reason why we can't have a sign that says "WEST I-10 TO I-110 / Downtown / Lafayette."