Maryland Gov. Larry Hogan said Wednesday that a state takeover of the Baltimore-Washington Parkway is the only “viable long-term solution” to fixing the pothole-ridden highway and bringing relief to the hundreds of thousands of commuters who use the route between Washington and Baltimore.

Hogan (R) is asking the state’s congressional delegation to support a transfer of the National Park Service’s portion of the parkway to the state. In turn, Hogan says, the state will make significant upgrades to the worn-out road — chief among them adding up to four toll lanes.

“We have reached a breaking point, with potholes, congestion, crashes and debris creating driving conditions so hazardous that the speed limit between Routes 197 and 32 had to be lowered to 40 miles per hour,” Hogan said in a letter to the state’s congressional delegation Wednesday. “These conditions are unacceptable for Maryland commuters.”

The Park Service this month lowered the posted speed limit to 40 mph from 55 mph after determining that the potholes were so bad in that five-mile stretch that it was unsafe to travel the posted speed. This winter’s dramatic temperature swings and repeated freezing and thawing created perfect conditions for the craters to multiply.

Park Service officials say that they have had a plan to resurface the road for a decade and that repaving has been done in segments as funding has become available. The section of parkway that is in the worst shape and where the speeds were lowered is expected to undergo a major repaving starting in the fall.

The number of motorists who have become stranded because of flat tires or damaged rims has been growing since last month, according to AAA crews. Some drivers have turned to Twitter to complain, calling the scenic parkway “hell on earth,” “a hot mess” and “downright dangerous.”

Sen. Chris Van Hollen (D-Md.) got so many complaints from constituents that he wrote to the Park Service last week, urging the agency to fix the road and calling its timeline for repairs unacceptable.

“It is an unsafe situation that needs to be remedied immediately through expedited action by the National Park Service and its federal partners,” Van Hollen wrote to Park Service acting director Dan Smith. “Lowering the speed limit is not an adequate substitute for repair, and it will not ensure the safety of Maryland commuters and other vehicles on this heavily traveled highway.”

The Park Service said this month that crews used more than 60 tons of asphalt to patch potholes in February and work on it daily as the weather allows. But the road has continued to deteriorate, the agency said. The Park Service owns the 19 miles of the roadway from the District line to Fort Meade.

Hogan criticized the Park Service’s response.

“NPS has increasingly demonstrated it is simply not up to the task of maintaining MD-295,” Hogan wrote in his letter. “It is clear that the state taking ownership of the parkway is the only viable long-term solution to these problems. We want to take over the road because it is the best way to take care of the road.”

In June, Maryland and the Interior Department announced an agreement to explore giving the state control of its portion of the parkway. The transfer would allow the state to pursue its plan to add four toll lanes to the parkway, which carries about 120,000 commuters daily. The Maryland Transportation Authority would build, operate and maintain the lanes.

Separately, Hogan is proposing to add four toll lanes on Maryland’s portion of the Capital Beltway and on a portion of Interstate 270 in Montgomery County.

Several business groups in Maryland and the Washington region have voiced support for the takeover and for the road expansion, saying it will help address congestion on one of the busiest thoroughfares in the region for commuting between Washington and Baltimore. The parkway connects to several major job centers, including NASA’s Goddard Space Flight Center, the National Security Agency at Fort Meade and Baltimore-Washington International Marshall Airport.

“The project will transform MD-295,” the Maryland Retailers Association said in a letter to Rep. C.A. Dutch Ruppersberger (D-Md.) last summer, echoing the message sent to various members of Congress in support of the state takeover of the highway.

“This transfer will allow the State to increase safety by upgrading the existing highway and to build and operate new express toll lanes, which will provide commuters with improved, expanded travel options between Baltimore City and Washington, D.C.,” the group said.