Healey’s plan, which would see $8 billion spent over the next 10 years, does not include tax increases. Instead, her office said the plan will maximize funds generated through the state’s Fair Share Amendment, also known as the “millionaire’s tax,” through borrowing and other existing resources.

The Bay State will spend upwards of $8 billion over the next ten years improving its roads, bridges and regional transportation services if a proposal announced by the governor Tuesday is passed by the legislature.

Gov. Maura Healey plans Wednesday to roll out a new plan to stabilize the MBTA's troubled finances and supercharge other transportation investments with billions of dollars in borrowing, fueled almost entirely by a voter-approved surtax on high earners.