A handful of visitors walk and watch the surf on Sand Beach in Acadia National Park on Sunday, Jan. 21, 2018. Credit: Bill Trotter

A bipartisan bill backed by U.S. Sen. Angus King proposes to generate up to $18 billion to eliminate the maintenance backlog at national parks.

Following a blueprint created by the Trump administration, the bill proposes to eliminate the National Park System’s $11.93 billion deferred maintenance deficit with revenue derived from energy produced on federal lands and waters.

King, an independent who caucuses with Democrats, called the bill “a practical step to help clear the existing maintenance backlog” that would also protect the parks.

[Acadia on track for another big year with visitors]

“For more than a century, our national parks have inspired and amazed countless visitors,” King said in a statement released Wednesday. “Unfortunately, these parks don’t take care of themselves — they need maintenance to ensure that future generations can experience the same wonder that so many Americans already have.”

About 330 million people visited the 417 National Park Service sites across the country in 2017. The service ​completed more than $650 million in maintenance work last year, but aging facilities, ​high visitation and resource constraints have kept the backlog at $11 billion to $12 billion since 2010, officials said.

One of three major park service holdings in Maine, Acadia National Park has a maintenance backlog of about $71 million, park officials have said, although a park service report said that as of September 2017, the deficit was a hair under $60 million.

[Trump’s interior secretary proposes hefty entrance fee hikes at Acadia]

Another holding, Katahdin Woods and Waters National Monument, hasn’t made it into a federal budget yet. Created in August 2016, Katahdin Woods is being built out largely with money donated by the Quimby family. A third holding, St. Croix International Historic Site, has a backlog of $875,104, according to the report.

Interior Secretary Ryan Zinke joined King, ​​U.S. ​Sen. Lamar Alexander, R-Tennessee, U.S. Rep. Mike Simpson, R-Indiana, and Rep. Kurt Schrader, D-Oregon, in introducing the bill on Wednesday.

Wednesday’s proposal is the third advocated by the Trump administration to reduce the park maintenance backlog. Zinke drew national attention in October when he proposed creating a new set of visitor-pass fees at 17 national parks, including Acadia. The new fee structure would raise national park revenue by $70 million annually, he has said.

[Park service cutting free entrance days at Acadia]

The steepest would increase Acadia’s weekly vehicle pass from $25 to $70 between June 1 and Oct. 31. U.S. Sens. Susan Collins and King as well as Maine U.S. Reps. Chellie Pingree and Bruce Poliquin signaled opposition to the plan by promising to review it.

The park service announced in January plans to reduce to four the number of days that visitors can gain free access to 118 of the service’s 417 units, including Acadia. That’s down from 10 free days last year and 16 in 2016, the year the system celebrated its 100th birthday.

Pingree is still studying the bill, according a statement from her spokeswoman.

“She is well aware of the need for more maintenance funding,” spokeswoman Victoria Bonney said. “She believes legislation is needed now to address improvements, from roads and trails, to wastewater systems and water pipelines.”

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