If we ever do get regional rail service on the inner Fitchburg, the whole Belmont-Waltham-Lexington triangle seems a good candidate for better bus service. While it's not the densest area, there are some decent-sized pockets of jobs and homes. The calculus for bus frequency changes massively when you can can connect to frequent rail on the Fitchburg Line rather than running extended routes to the Red Line or downtown.
If RER can't fix a broken, dysfunctional, Lynn Terminal, RER is not going to fix the broken, dysfunctional, Waltham Terminal.
Like with Lynn, RER from Waltham does not follow the path of where all of Waltham's buses and urban densities go. Look at the Waltham streetcar map above. All of Waltham's historical streetcar lines, with it's urban densities, are all oriented towards Watertown Sq. and Newton Corner, and not the CR to Belmont. RER is not going to fix the broken Watertown Sq. bus terminal, since there is no CR at Watertown Sq. RER does not hit all color change transfers, neither Waltham or Newton Corner CR have a Blue Line connection, and Newton Corner CR also lacks a GL connection. RER fare integration with bus + subway is problematic, compared to just bus + subway.
One can electrify the Fitchburg & Worcester Lines, plop in an infill in Newton Corner on the B & A, and run 7.5 minute headways as much as desired on both of the RER lines. Yet all of Waltham's bus headways are still going to be eaten up by the 70, the 505, and in the pre-COVID era, all of Waltham's 55x buses, making distended super-extended runs to Cambridge and Downtown. Waltham's buses cannot cycle efficiently back and forth to Waltham Terminal because those super extended runs means all of Waltham's buses get stuck in Mass Pike traffic, or getting bunched making the long 16 kilometer slog through Arsenal St. and Western Ave. to hit all of those color change rapid transit transfers bringing riders where they want to go. The 70 bus to Waltham is
among the top 10 most bunched routes in the MBTA system, because 16 kilometers of street running in mixed traffic kills reliability completely, and running a 16 kilometer route on KBR headways under BNRD is going to consume a lot of buses. Why did
the 70 between Watertown Sq. and Waltham get KBR status in BNRD, and not the 54 to Belmont that parallels the CR? It's because riders from Waltham Center want to get to Watertown Sq. and Newton Corner, not Belmont.
CR/RER to Belmont does not bring Waltham riders where they want to go, so RER can't possibly fix the broken Waltham bus terminal. Riders constantly fill buses to Watertown Sq. from Waltham and buses to Wonderland from Lynn. The historical
Watertown Branch Railroad is one of the few branch railroads to ever have seen such signficant heavy traffic it had to be double tracked the entire length, serving as the primary railroad connection to Waltham, not the main line via Belmont.
The 55x bus routes were cut back to Newton Corner due to COVID, WFH, & the lack of bus operators. BNRD is going to cut back and reduce Waltham's bus system (mostly the 55x routes being axed), aside from upgrading the 70 to KBR. This essentially causes all those last mile shares from Waltham to be inaccessible to the rapid transit system and killing potential ridership, since one has got to take two buses to reach those rapid transit color transfers, or pay an extremely expensive bus fare + CR fare with no free/discounted transfer + an additional transfer from RER to the Red/Orange to hit the Blue/Green transfers.
Given how F-Line comments about RER vs HRT to Lynn, I'm under the impression that with no rapid transit to Watertown Square, Newton Corner, or Waltham Terminal, means that one is never going to get any meaningful bus headways for last mile shares out from Waltham Terminal, even with RER. Only a proper HRT extension hitting all 3 terminals are ever going to give one any meaningful bus headways for last mile shares in the Waltham area. High frequency urban rail from Waltham has got to hit Watertown Sq., not Belmont.
If one wants better bus service to Waltham, one has got to start with bringing rapid transit to Newton Corner and Watertown Square, then extend one of those rapid transit lines all the way to Waltham Terminal.
If one can pull off BLX to Newton Corner via the B & A alignment, one will be able to instantly nuke all of those express buses, and get balanced 1:1 bus cycling out from the Newton Corner terminal. The bus headways redistribution will instantly be able to provide a rudimentary level of service across the Waltham area & prop up demand for those last mile shares.
GLX from Union to Watertown Sq. via Porter could help, potentially allowing the 70 bus to be split into 2 separate routes at Watertown Sq. and finally allowing Watertown Terminal to have balanced 1:1 bus cycling. The western segment of the 70 to Waltham would still be load bearing. That could be fixed with an extension of rapid transit from Watertown Sq. to Waltham Center, whether with BLX from Newton Corner via Watertown Sq., or GLX from Watertown Sq. to Waltham Terminal.
Once one has got a Waltham - Watertown rapid transit extension, the western segment of the 70 bus would no longer be load bearing. Now at last, all those bus headways are now finally freed up and can be reinvested across the entirity of the Waltham area to provide increased frequencies for all those last mile shares, and possibly add crosstown routes to Lexington and Arlington, with balanced 1:1 bus cycling out from Waltham Terminal.
No rapid transit to Newton Corner, Watertown Sq., or Waltham, likely means no improved bus service in the Waltham area. It's only fixed with rapid transit extensions hitting all three bus terminals finally allowing bus service to be improved in the Waltham area with balanced 1:1 bus cycling from all of the terminals, and get those last mile and crosstown shares. It was back in 1972 when the MBTA decided to extend the 70 all the way to Waltham, dragging out Waltham's buses all out onto super-extended distended runs to Cambridge and Downtown and destroying Waltham bus headways & reliability, 52 years ago.