The project would connect Boston's South and North stations.Photo – Massachusetts Department of Transportation
The Massachusetts Bay Transportation Authority's (MBTA) proposed North South commuter-rail project could cost $12.3 billion to $21.5 billion, according to an ongoing feasibility study.
The project calls for building 2.8-mile-long tunnels to connect Boston's North and South stations. The cost estimates cover tunnel construction, new or additional locomotives or coaches, improvements to support higher service levels and risk contingencies, MBTA officials said in a press release.