Rep. John Shadegg, R-Ariz., says he wants public hearings on the National Park Service plan to designate nearly 95 percent of the Grand Canyon National Park as wilderness.

Shadegg said Thursday the plan was based largely on information gathered in the 1980s and that no public hearings on the matter have been held in 22 years.Even though part of the park should get the designation, the wide range of ramifications makes doing it without public input unacceptable, the Arizona Republican said.

"I think a person in my district is almost totally unaware of its far-reaching implications," Shadegg said.

The Park Service said in June that by the end of the year it hoped to be treating 94 percent of the 1.3 million-acre park as if it had been designated a wilderness area.

The effect, among other things, would be to prevent development of roads and buildings. Also, motorized vehicles would be prohibited in the portion being treated as wilderness, and more than 120 miles of old roads would have to be turned into trails or restored to their natural condition. It also could mean rangers would have to use picks and shovels rather than mechanized equipment to repair trails.

Five of the roads lead to overlooks, and their conversion would make handicapped access difficult to those spots, some say.

Rafters also are concerned that a corresponding wilderness treatment plan for the Colorado River will end commercial motorized boat travel.

Kim Crumbo, Grand Canyon National Park wilderness coordinator, said the road closings are necessary to preserve some of the last old-growth ponderosa pines in the United States.

Crumbo said there are other roads on national park property and adjacent public lands to provide alternative access for the disabled into the trail areas and to other overlooks.

Other officials have said the wilderness move is needed because of constant pressure to open the park to new uses, including such projects as helicopter landing pads, a gondola from the rim to the river, new hotel lodges and even floating casinos.

Actual designation of 1.1 million acres as wilderness would require congressional approval, and the service said it hopes to get that. In the meantime, treating the land as if it were so designated is within Park Service authority, officials said in June.

A spokeswoman for park superintendent Robert Arnberger said he will initiate serious discussions about increasing public involvement in the wilderness planning process and will review any questions brought up.