Costly train safety upgrades will force some MBTA service disruptions

BOSTON — Commuter rail riders can expect some weekend closures starting next spring as the MBTA embarks on a $459 million effort to bring the sprawling system into compliance with a federal safety mandate.
The commuter rail line leading to Providence, R.I., is the only line with positive train control, a requirement of the Federal Railroad Administration, according to Bradley Kesler, chief railroad officer for the T.