Gov. Larry Hogan announced Tuesday he will spend $461 million to ease congestion on the northern rim of the Baltimore Beltway.

The plan would convert 19 miles of the fast lane shoulders in both directions on I-695 into new travel lanes between I-70 and Parkville, a move state officials said would cut about 15 minutes off rush hour delays that can stretch an hour or more.

Hogan’s plan would also nearly double the length of the northbound express toll ways on I-95 — from White Marsh to Bel Air — in order to speed traffic along, and rebuild the interchange at I-70 and I-695 to mitigate a daily bottleneck there.

Commuters would also see stop lights at on-ramps to help manage traffic flow. Five bridges would be rebuilt, and new four new sound walls would be installed.

Construction would begin no later than late summer 2018, state officials said.

Ragina Cooper-Averella, spokeswoman of AAA-Mid-Atlantic, said her organization supports the road investments as “good news” for motorists, and she supports them as a commuter who sits in that congestion from her Bel Air home to her Towson office.

“The congestion is horrible in that area, it really is,” she said. “Every time I take those express ways, I wish they extended further.”

But some transportation advocates questioned whether widening the Beltway would solve congestion long-term or simply invite more motorists to start using the roadway.

Brian O’Malley, president and CEO of the Central Maryland Transportation Alliance, said his group is “agnostic” about which mode of transportation is best, but added there’s little evidence across the country that additional traffic lanes reduce gridlock for long.

“No one has been able to build their way out of their congestion,” he said.

Maryland Transportation Secretary Pete K. Rahn described the administration’s strategy simply.

“We’re targeting congestion,” Rahn said.

The Baltimore plan announced Tuesday does not require legislative approval.

The most costly piece of the plan extends express toll lanes on 7.75 miles of I-95. That $210 million project will be overseen by the Maryland Transportation Authority, whose projects are generally paid for with money from tollways.

Hogan, who announced the plan at State Highway Administration headquarters in Hanover, described the plan as part an ongoing effort to improve road infrastructure in the state.

Earlier this year, Hogan announced a $9 billion idea to install express toll lanes on the Capital Beltway through the Washington suburbs and to widen the Baltimore Washington Parkway.

The governor, a Republican, campaigned in 2014 against the gas tax increase that is now being used to finance road projects across the state. In his first year in office, he attempted to roll back part of that increase.

On Tuesday, Hogan said he still did not support the tax, but that since the state has the money “we’re spending it as wisely as we possibly can.”

Hogan has come under fire from transit advocates for heavily investing in roads and the expense of other transportation options.

In addition to the $9 billion plan to add toll lanes to major highways, transit advocates continue to criticize his 2015 decision to cancel the proposed $2.9 billion Red Line light rail project in Baltimore, which he called a “boondoggle.”

Instead, Hogan earlier this year revamped the city’s bus system at a cost of $135 million.