The MTA announced a formal feasibility study on July 17 to add a second track and electrify the single-track diesel LIRR branch between Ronkonkoma and Riverhead, with findings expected in early 2027. The announcement came at the ribbon-cutting for the new Yaphank-BNL station, the first new LIRR station on Long Island since 2021.

The LIRR branch east of Ronkonkoma is a different railroad from the one most commuters know: a single track, diesel power, and service frequencies that don't match the electrified main. The MTA took the first formal step toward changing that Thursday, announcing a feasibility study for double-tracking and electrifying the branch — timed to the ribbon-cutting of a new station in eastern Suffolk that itself took half a century to materialize.

The Yaphank-BNL station opened July 17, 2026, replacing the old Yaphank stop and relocating it closer to Brookhaven National Laboratory and the Long Island Expressway interchange. Revenue service began the morning of July 18, with the first trains departing Yaphank-BNL at 5:36 a.m. to Greenport and 8:02 a.m. to Ronkonkoma. The station is the first new LIRR stop on Long Island since the Elmont-UBS Arena station in 2021, and only the second to open in 50 years.

At the ceremony, MTA Chair and CEO Janno Lieber announced that a feasibility study is now underway covering the Ronkonkoma Branch east of Ronkonkoma Station. The study is evaluating three potential upgrades: signal and communications modernization; adding a second track along all or part of the Ronkonkoma-to-Riverhead corridor; and electrifying a portion of the branch. A completed second track would extend the LIRR's Double Track Project, which brought two-track operations to the Farmingdale-to-Ronkonkoma corridor, into the diesel territory east of it.

"Now that it's open, we can ramp up the feasibility study now underway that's exploring new ways to improve and increase service on the Ronkonkoma branch," Lieber said in the official statement.

The study will also model the supporting infrastructure electrification would require — power substations among them — and weigh costs against projected benefits. Results are expected in early 2027. The work is funded by the MTA's $68 billion 2025-2029 Capital Plan, fully appropriated by Governor Hochul and the legislature in the FY 2026 budget.

The announcement came four days after the MTA confirmed a separate $7.5 million federal grant to fund preliminary design on eliminating three at-grade crossings west of Ronkonkoma — at Brentwood, Wyandanch, and Central Islip. Taken together, the two moves represent the most concentrated capital attention the full Ronkonkoma Branch has seen in years: grade separation and double-track design on the electrified western segment, a formal study for the single-track diesel stretch to the east.

For riders east of Ronkonkoma, the early-2027 findings won't be a capital commitment — the MTA says they will inform "future conversations with the public about investment priorities." What those findings will provide is a cost-and-feasibility number that hasn't existed before: what it would actually take to run electric trains on two tracks from Ronkonkoma to Riverhead.