This post comes from MSN Money contributor Tanya Mohn.

Beach, Welfleet MA © Jeffrey Coolidge, Photodisc, Getty Images
Travelers hoping to enjoy the splendor of the great outdoors this spring and summer should be prepared for cutbacks at the nation's 398 National Park Service sites.

The cutbacks would result from the looming sequester -- automatic spending cuts that will take effect Friday if Congress can't agree on a plan to address the national debt. If this happens, the National Park Service would be cut by more than $110 million, according to estimates, which would affect every park in the system.

"A one-time cut of this magnitude is more damaging than any the Park Service has ever faced, at least in recent history,"said John Garder of the National Parks Conservation Association. "The mindless across-the-board cuts are so bad, they should never be allowed to happen."

The proposed 5.1% cut is especially worrisome, Garder said, because it would be on top of reduced funding that has occurred in recent years, and many parks already lack the resources necessary to operate.

Char Miller, a professor and director of the environmental analysis program at Pomona College, said the parks have "already been cut to the bone."

"The significant cutbacks will be felt by visitors to any national park, and will be visible from maintenance on trails and visitor services to the presence of park rangers," he said.

The Coalition of National Park Service Retirees has posted a detailed list of how sequestration-relate​d cuts are expected to be implemented. The information is based on internal National Park Service memos and other sources, said spokeswoman Joan Anzelmo.

Among them:

  • Yellowstone National Park will delay spring road openings in the park and to the west, south, east and northeast entrances. "Savings would come from a combination of reduced or delayed seasonal hiring, extended unpaid furloughs for employees, and reduced operating expenses including fuel, equipment and maintenance," the coalition says.
  • Grand Canyon National Park will delay opening the East and West Rim drives and reduce hours of operation at the main visitor center.
  • Yosemite National Park will delay the opening of the Tioga and Glacier Point roads by up to four weeks.
  • Glacier National Park will delay opening the Going-to-the-Sun Road by two weeks. It's the only road across the park.
  • In Grand Teton National Park, theJenny Lake Visitor Center, the Laurence S. Rockefeller Preserve and the Flagg Ranch Visitor Contact Station will remain closed for the summer.  
  • Great Smoky Mountains National Park will close five campgrounds and picnic areas. 
  • Cape Cod National Seashore will close the Province Lands Visitor Center for the season. Also, access to large sections of the Great Beach will be reduced.
  • Along the Natchez Trace Parkway, 25 comfort stations will be closed one day each week.
  • Mount Rainier National Park will close the Ohanapecosh Visitor Center.
  • Denali National Park willpostpone the opening of the Eielson Visitor Center.

If you're flying to a city near your national park of choice, sequestration could affect that experience too.

"These across-the-board cuts may punish travelers with flight delays, long security lines at Transportation Security Agency checkpoints and multi-hour waits to clear Customs and Border Protection," Roger Dow, the president and chief executive of the U.S. Travel Association, said in a statement. 

Park advocates say that not only the parks will suffer if Congress does not act in time. Communities and businesses that rely on park tourism would also be hurt if visitors, including international tourists, decide to go somewhere else.

"Our national parks generate $31 billion from tourism and recreation alone. Every dollar invested yields $10 of economic activity," said Garder, who recommends that people contact their members of Congress to ensure that national parks "don't fall through the cracks."

"If they do, long term it will ultimately damage the locations and the ability for families and others to visit these inspiring destinations, and the countless local economies that depend on them," he said.

A recent poll conducted by the association and the National Park Hospitality Association found that nine out of 10 Americans do not want additional cuts made to already strapped national park budgets. "National parks are widely supported across the political spectrum," Garder said.

Do you have a vacation planned to a national park this spring or summer? Have the looming budget cuts caused you to re-evaluate your plans?

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