The train replacement project is designed to increase capacity on the two metro lines and is part of a wider programme approved by state governor Mr Deval Patrick to improve two highways and replace a road bridge in Boston.

A pre-bid meeting will be held on December 3 for the procurement of the trains. MBTA requires 152 cars for the Orange Line, plus 74 cars for the Red Line with an option for an additional 58 cars.

MBTA says it wants the new cars to provide improved reliability, accessibility and energy efficiency. It wants increased capacity and additional seating compared with the existing trains, wider and electrically-operated doors, four accessible areas per car, LED lighting, modern HVAC systems and advanced passenger information and announcement systems. MBTA expects to award the contract by winter 2014-15, and has stipulated that final assembly should take place in Massachusetts. Following extensive pilot train testing, Orange Line car delivery is scheduled to begin in winter 2018-19 with the delivery of the Red Line cars following in autumn 2019.

"Our customers on the Orange and Red lines have been waiting for years to see these long-discussed investments become a reality," says MBTA general manager Dr Beverly Scott. "New cars will provide reliable service while increasing seating capacity and accessibility for all riders."