As one of the most important—and most problematic—interlockings in the system, it seems only appropriate to start this series with Rogers Junction. Rogers Junction lies near beginning/end of the IRT Eastern Parkway Line (very close underneath Rogers Av on the surface), between Franklin Av and Nostrand Av or President St, depending on which way you go. It is at this point that the (2) (3) (4) (5) services join together into one line. The (2) and (5) turn south down Nostrand Av and continue a couple miles before terminating at Flatbush Av, while the (3) and (4) keep going east under Eastern Parkway just a couple stops to Utica Av.
Rogers Junction - Upper Level
Flying Junction
Rogers Junction has proved problematic over the years as the IRT chose to build it in a cheaper and more antiquated manner. A modern version of this junction would have made use of a flying junction, wherein lines only merge on the track that they need to merge on, and any other grade crossings are eliminated. The photo on the left shows an example of a flying junction outside of Delancey St/Essex St, where the (M) line merges with the (J) (Z). Although the routes are simpler here, the principle is the same and could be applied at Rogers. With the current service pattern of the Eastern Parkway line, the (5) merges with the (2) (3), and then the (2) and (5) switch to the Nostrand Av line and turn south. This causes a major bottleneck at peak hours when all lines are running at capacity, especially as the (2) (3) (4) (5) remain some of the busiest lines in the system. When there is any delay at Rogers, no matter how slight, it causes bigger delays down the lines as wait times add up more and more and crowds build, causing further delays. Furthermore, when there is a malfunction, things get very complicated. Just a few weeks ago, on July 22nd, a switch malfunction at Rogers Junction (supposedly caused by extreme heat in the tunnel, which I can certainly vouch for after being there in person) caused major disruptions and service changes starting mid afternoon and running late into the night, ruining many evening rush hour commutes. (2) trains were terminating at South Ferry in Manhattan and (5) trains at Bowling Green. (3) and (4) trains were running express on all of Eastern Parkway with extreme delays due to a slow speed order in the vicinity of Rogers Junction. This cascade of problems, at least for the most part, could be avoided with a rebuild of the interlocking.
Unfortunately, there are only really two solutions. The interlocking cannot simply be reconfigured. Not only would it be obscenely expensive to do so (the full reconstruction option costing nearly $1.6 billion and the lesser option still over $340 million), but it would also require at least a partial demolition and rebuilding of Eastern Parkway on the surface, and the tunnel would have to be completely reconstructed. On top of that, both the Nostrand Av and President St stations occur within extremely close proximity to the interlocking, meaning one, if not both, of these stations would need to be closed in order to rebuild the junction. The other solution would be to change the service pattern of IRT Brooklyn trains. Some (3) trains would be sent to Flatbush Av and the (5) would always be sent to Utica Av via the express, so the (4) and (5) would continue down the Eastern Parkway express while the (2) and some (3) trains would go down Nostrand Av, and some (3) would stay on the Eastern Parkway local. This would eliminate the bottleneck and allow the lost train capacity on the Brooklyn lines to come back, but it would be unfavorable for Nostrand Av Line residents and is probably less likely to be pursued than an incredibly expensive reconstruction.
No matter how many problems it causes, there is no denying Rogers is one of the most important interlockings in the system, which is demonstrated by the level of disruption it has the potential to cause.
Click here to read the official study done by the MTA for the rebuilding of Rogers Junction.
