Okay, so this is one part of my soft-proposal for a shuttle underneath Fordham Road and Pelham Parkway, with potential additional service to Pelham Bay Park to completely connect to the 6. I need to do more research before I can make a full-length proposal in any form, but I do think this community should add to it and voice opinions about it.

The Idea

The Bx12 bus is easily one of, if not, the single most used bus route in The Bronx. It's an essential crosstown route that also experiences dangerous overcrowding, no matter where you board or exit from. People pushed against the doors, passengers standing directly next to the driver, and that's not even factoring in wheelchairs or the backpacks that hadn't been taken off. The regular Bx12 runs from Sedgwick Avenue to Pelham Bay Park, while Bx12-SBS runs from Inwood-207 Street to Bay Plaza, both via Fordham Road/Pelham Parkway. Both roads are heavily used, and extremely dense in population as the BX12 provides direct service between the A/B/D/1/2/4/5/6 and Metro North (no other Bronx bus route does that to my knowledge, the Bx36 doesn't even reach the A and has no direct connection to the 4 as there's no stop at Tremont Avenue for the Jerome Avenue line).
Let's recap: The Bx12 is the only crosstown line to connect SEVEN subway lines to each other and Metro North. It's also horrendously overcrowded, no longer ADA accessible as a result during midday and rush hours, and was chronically slow due to the traffic. How can we solve this?
A crosstown shuttle.
This shuttle would run from Sedgwick Avenue to Eastchester Road - maybe potentially Pelham Bay Park - via Fordham Road and Pelham Parkway, serving the busiest (and some ignored) Bx12 stops and streets. The shuttle would run 24/7 on this route, serving some of the busier Bx12 stops, and providing consistent service along the route, whereas the Bx12 is prone to skipping some stops even if there's people waiting at the stop that's skipped.
This shuttle would also provide direct connections to all lines the BX12 connects to within the Bronx.
So, without further introduction, I'm ready to present:

The Fordham/Pelham Shuttle

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The general route, with 207th Street included as proof of concept. Connecting 207 to Fordham may not be possible due to the limitations of the bridge and the possible depth of the river, but that bit of service can be sacrificed.
Stops (with details):
[Phase 1]

• Sedgwick Avenue - Western terminus for BX12 during the day.
• University Avenue
• Jerome Avenue (Transfer to 4)
• Grand Concourse - Valentine Avenue (Transfer to B/D) - A transit hotspot, this area is where the Bx1/2, Bx12, Bx22, Bx34, and Bx9 meet and where the B/D stops at. But instead of stopping at either Grand Concourse OR Valentine Avenue, this would stop at the stretch between them, with exits at either side making Fordham Road on the Concourse line a complex.
• Webste3rd Avenue - Fordham University (Connection to MNR, Transfer to BX41-SBS) - The same logic applies here as is with GC-Valentine above; This area is where the Bx9, Bx12, Bx15, Bx17, Bx22, and Bx41 meet. This also serves as a terminal for the Bx15 and Bx17, with a connection to the Harlem and New Haven lines, and would enable a much faster commute to Fordham University for students.
• Arthur Avenue
• Southern Boulevard - Bronx Zoo - This area is the last part where the Bx9 runs on Fordham, where it turns onto Southern Boulevard and joins the Bx19. This is also the second to last (or sometimes the last) stop on the Bx19, so this is a transfer point for those who board the Bx9 - where the Bx12 does not reach - on Kingsbridge looking to get to a stop along Fordham or Pelham much faster. This area also contributes to the extreme overcrowding
• White Plains Road (Transfer to 2/5) - This functions as a major transfer area as well, as passengers getting off the 2 train transfer to the Bx12 for service toward Pelham Bay Park. But this can also be an area where the potential crowding on the crosstown shuttle would ease up for those looking to get to Wakefield or for service to the South Bronx.
• Bronxwood Avenue
• Williamsbridge Road (Transfer to 5) - The last stop for Phase 1, this would provide direct service to the 5 from Jerome Avenue without needing to rely on the Bx12 or the 4 to transfer.

[Phase 2]

• Wilson Avenue
• Eastchester Road
• Stillwell Avenue
• Mayflower Avenue - Does not receive service from the Bx12
• Pelham Bay Park* (Transfer to 6) - Eastern terminus of the Bx12

*Possible but not necessary.
Some of these areas are filler stops, such as Bronxwood Avenue, Wilson Avenue, Stillwell Avenue, and Mayflower Avenue. But the others are very important and densely populated areas with tons of shops and foot traffic.
There may be some concern, as this essentially IS the local Bx12 route. However, both the Bx12 and Bx12-SBS make some stops this shuttle would bypass to keep even spacing between stations. And to add on, this would be the route 24/7, while the local Bx12 gets extended during nights to Inwood and Bay Plaza, providing additional service the shuttle cannot provide.
Fleet: This line can use a small fleet of R68s at half length (four cars, as opposed to eight) and can be connected to the Concourse yard, with a small layup yard akin to that of Church Avenue on the G either near Sedgwick Avenue or Eastchester Road/Pelham Bay Park.
The stretch I'm most concerned about is from Jerome to Webster.
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This section on the Bx12 is the busiest portion, leading to my well warranted concern.
This specific stretch of the Bx12 is where everyone starts packing together far too closely, where everyone starts getting pushed against the doors. Children and the elderly and senior take the Bx12 to commute, making this section incredibly dangerous to board or exit. On top of this issue, it's extremely hard to breathe when there is 90+ people crammed onto one single bus. Increasing frequency does not solve this either, as the Bx12-SBS runs back-to-back, and no matter how close or how far apart they are, they're all crowded beyond reasonability.
Another issue is accessibility for the disabled.
Because of the crowding, those in wheelchairs or walkers cannot safely board and use the accessible areas. And when you include the parents who refuse to close their strollers or those who bring very full shopping carts on the bus, it progressively gets more and more dangerous.
This shuttle would not replace Bx12 service, but rather supplement it, as they would take the traffic that would normally go on the Bx12. Residents and employees of the area now have an option between the Bx12 OR the shuttle, depending on their destination. The shuttle would skip some stops the Bx12 would make, such as Elm Place, and the base plan would not go past Sedgwick Avenue (meaning Cedar Avenue would not be served), but the shuttle also serves some stops the Bx12 directly does NOT (Mayflower Avenue and Arthur Avenue).
The Harlem River requires some more research, so if anybody has any info regarding its depth and terrain they can provide, please do comment on this. That's crucial for extending the shuttle beyond Sedgwick Avenue to Inwood. Hopefully we can create a full proposal together, should anyone agree with me on this idea.

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