A reading frenzy was kicked off Tuesday when a massive draft plan for managing the wild and scenic Merced River through Yosemite National Park was released, a plan park officials hope will end years of litigation over visitor impacts on both the river and the Yosemite Valley.

Reaction to the voluminous document was muted, as groups with interests in the final plan said they needed time to digest the draft. So big was the plan that Yosemite officials created a 20-page summary guide to help interested parties understand what was in the full draft.

Greg Adair, whose group, Friends of the Yosemite Valley, twice took Yosemite officials all the way to the 9th U.S. Circuit Court of Appeals over previous iterations of the plan, said he hoped that within the roughly 2,500 pages the Park Service had carefully studied both the visitor experience and the Yosemite Valley's ecosystems in arriving at a daily carrying capacity for visitation.

“We really haven’t seen them do that" in the past," Mr. Adair said during a phone call. "Our concern would be to see if they’ve finally done that.”

A review of the park's preferred alternative shows it would set a daily visitation cap of 19,900 to the Yosemite Valley, roughly equal to current levels. Additionally, the preferred alternative calls for a 37 percent increase in campsites in the valley, a 5 percent increase in day-use parking areas in the valley, and a slight, 2 percent increase in valley lodging.

At the same time, the draft notes the preferred alternative would restore 203 acres of meadow and riparian areas, the Sugar Pine Bridge upstream of the Ahwahanee Bridge would be removed "to enhance the free-flowing condition" of the Merced River, and 34 campsites within 100 feet of the river in the North Pines, Backpackers, and Lower Pines campgrounds would be removed.

A recreational vehicle loop with 36 sites also would be built in the Upper Pines Campground under the preferred alternative. And the draft plan calls for continued use of "rafts, kayaks, paddle boards, inner tubes, and inflatable mattresses" on the Merced River through the valley. If day-use parking areas continued to be overwhelmed, the draft plan says a permit system could be instituted.

Yosemite officials were deluged Tuesday afternoon with calls from reporters seeking comment and not immediately available to discuss the plan. But in the 20-page summary guide, they talked about the preferred alternative's approach to restoring heavily used areas of the Yosemite Valley.

A 150-foot riparian buffer, measured from the ordinary high-water mark, would be protected and enhanced corridorwide. Eroded riverbanks would be repaired through restoration, and vulnerable riverbanks and riparian vegetation would be protected from trampling. Visitors would be directed to use resilient areas, such as low-angle sandbar beaches. Ditches in meadows would be filled, six miles of informal trails in meadows and riparian areas would be removed, and abandoned underground infrastructure would be removed. Informal roadside parking along meadows and associated fill material would be removed to restore meadow area and protect meadows from informal trailing. Cultural resources, such as archeological sites would be protected from irretrievable loss.

The Merced River was designated a "wild and scenic river" in 1987. As such, park officials must protect the Merced's outstanding remarkable values, its stream flows, and its water quality. Differing views over those points have long delayed an updated management plan for the Yosemite Valley, as groups that opposed the Park Service's proposals successfully battled the agency in the court system.

The gist of the litigation -- which claimed the Park Service was allowing inappropriate development to intrude upon the wild and scenic river corridor-- began shortly after Yosemite officials completed their first Merced Wild and Scenic River Comprehensive Management plan in August 2000.

It was late in September 2009 when the Park Service and the Friends of Yosemite Valley and Mariposans for the Environment and Responsible Government settled their differences over the Merced River Plan and agreed to stop sending their lawyers to court.

Emily Schrepf, the Central Valley program manager for the National Parks Conservation Association, was cautiously optimistic Tuesday that the plan would succeed.

“A big part of the preferred alternative is to use a lot more public transportation, increased buses and shuttles, and an intelligent transportation system" to move visitors through the park in a less congested way than now is experienced, she said from her Fresno, Calif., office. “I think they’re really, really working to avoid any sort of limits that would turn people away."