Oak Grove station

Oak Grove opened on March 20, 1977, as the northern terminus of the Haymarket North Extension of the Orange Line.[1] Originally intended to run as far as Reading, displacing inner Haverhill Line service, the extension had been cut back to Oak Grove by the time the station was completed. However, a platform (sized for six-car Orange Line trains rather than lengthier commuter rail trains) was built to serve the single Haverhill Line track, for potential use should the remainder of the extension be built. In the fare mezzanine, a sign labels the platform as "Orange Line outbound". Malden Center was built with the same configuration; however, its platform is regularly used for commuter rail service.

Haverhill Line trains do not stop at Oak Grove unless the Orange Line or the Haverhill Line is disrupted between there and North Station, necessitating a transfer between modes. After the approach trestles at North Station burned on January 20, 1984, Oak Grove became the inbound terminus for the Haverhill Line. When North Station reopened on April 20, 1985, commuter trains no longer stopped at Oak Grove. Instead, most trains make a stop at Malden Center, which is closer to employment areas in downtown Malden.[1] The switch may have been made due to a request by John A. Brennan Jr., who was then constructing a large development near Malden Center station.[3]

Because of its Orange Line connection, Oak Grove can serve as a temporary inbound terminus for Haverhill Line service when commuter rail service is disrupted between Oak Grove and Boston's North Station. It served this role during the 2004 Democratic National Convention, when North Station was closed for a week for security purposes.[1]

The design of Oak Grove station was based on that of North Quincy.[4] In October 1997, Oak Grove was identified as a possible site for a parking garage, but this was never pursued.[5]

The 2014-constructed emergency exit

During 2013, the MBTA performed heavy maintenance on the Orange Line platform, which had substantially deteriorated during 36 years of operation. High-pressure water was used to strip away the top layer of concrete; a smoother top coat and new tactile platform edging were installed. The work was performed on one side of the platform at a time with no station closures.[6] The project also included new track lighting, guardrails, and expansion joints.[7]

The project, originally expected to cost $2.3 million, was issued a notice to proceed in December 2012. Phase 1, which lasted from April to August 2013, focused on the inbound side of the platform. Original plans called for an exit-only ramp on the north end of the Orange Line platform to be constructed as part of Phase 1; however, this was put off due to the discovery of buried utilities not present on site plans. Phase 2, from August to December 2013, focused on the outbound side of the platform.[7] From March 2 to June 30, 2014, the MBTA constructed the emergency exit ramp and a public restroom as Phase 3.[6]

The existing elevators, which connect the fare mezzanine to the Orange Line platform and the busway, were built with the station and renovated in 1987.[8][9] (This made Oak Grove the first Orange Line station to be accessible.)[10][11] Three elevators are being added to the station - an elevator between Washington Street and the mezzanine, a redundant elevator between the mezzanine and the platform, and a redundant elevator between the busway and the mezzanine - and one existing elevator renovated.[12] The MBTA awarded a $22.5 million construction contract in August 2019.[13] Construction is expected to last until mid-2021, with the Washington Street elevator completed by the end of 2020.[14][12]