Yellowstone National Park vehicle traffic nearing capacity

Matthew Brown / AP

CHEYENNE, Wyo. — Sometime within the next four to six years, Yellowstone National Park is expected to reach its capacity for being able to handle all the vehicles that tourists drive through the park to see sights like Old Faithful, wild wolves and grizzly bears and spectacular scenery.

Potential solutions include instituting a reservation system or passenger shuttles to control the number of visitors during peak times for the busiest attractions in the park, but no decisions will be made for at least a couple of years, according to the National Park Service.

"Historic and recent trends demonstrate that visitation will increase over the long-term, therefore, it is imperative for us to plan now," Yellowstone Superintendent Dan Wenk said in a statement. "Good visitor use management will allow the park to protect resources, encourage access, and improve experiences."

The agency on Thursday released a pair of studies looking at traffic and parking in the nation's first national park and visitor demographics and expectations.

Based on conservative estimates of visitor growth to the park, the traffic study said the nation's first national park should expect to exceed its overall vehicular capacity by 2021-2023.

"The more popular areas of the park are already over capacity under current conditions during peak season," the study noted.

Two-thirds of the more than 1,250 visitors surveyed in August 2016 said that finding available parking is a problem and more than half think there are too many people in the park.

The report recommended additional traffic studies within the park and the Greater Yellowstone region to help park officials develop solutions that could include developing a plan that "evaluates and defines visitor capacities for key locations in the park."

One suggestion the report made was that park service officials might consider managing the number of visitors to the busy geyser basin attractions during peak time through "reservation systems."

Using shuttles, which have been adopted by some other national parks, is another possible solution.

The park service pledged to gather more information through 2019 that "will guide the park in evaluating trade-offs in visitor experience and developing the most appropriate strategies to address summer season visitor use challenges." It promised to listen to all concerns to help shape any actions.

Yellowstone spokeswoman Morgan Warthin said Thursday that no decisions are imminent and that the park considers the matter to be in a "pre-planning phase."

More than 4.25 million people visited Yellowstone in 2016.

According to the survey of park visitors, 83 percent of Yellowstone's visitors come from the United States and 17 percent come from abroad with people from Europe and China the top two respectively among international travelers.