President Obama signed legislation Monday setting aside more than 2 million acres in nine states as protected wilderness.
The bill includes $8 million to $12 million to create an interpretive geologic trail that tracks the Ice Age floods that carved out much of the unique geography of Eastern Washington.
The 600-mile Ice Age Flood Trail would include interpretive centers, signs and markers so motorists can track the trail of the massive floods caused when an ice dam in what is now Montana collapsed, draining glacial Lake Missoula's 500 cubic miles of water.
The floods 13,000 to 18,000 years ago cut the coulees, ridges and buttes of today's Eastern Washington, including the Columbia River Gorge. The National Park Service will oversee the new trail.
Obama called the new public lands law among the most important in decades "to protect, preserve and pass down our nation's most treasured landscapes to future generations."
At a White House ceremony, Obama said the law guarantees that Americans "will not take our forests, rivers, oceans, national parks, monuments, and wilderness areas for granted, but rather we will set them aside and guard their sanctity for everyone to share. That's something all Americans can support."
The law -- a collection of nearly 170 separate public lands, parks and water measures -- represents one of the largest expansions of wilderness protection in a quarter-century. The measure confers the government's highest level of protection on land in nine states -- almost as much wilderness as designated during the past eight years combined.
Land protected by the 1,200-page law ranges from California's Sierra Nevada and Oregon's Mount Hood to Rocky Mountain National Park in Colorado and parts of the Jefferson National Forest in Virginia.
Land in Idaho's Owyhee canyons; Pictured Rocks National Lakeshore in Michigan; San Miguel County, N.M.; Zion National Park in Utah; and the Monongahela National Forest in West Virginia also won wilderness protection.
In addition, more than 1,000 miles of rivers in several states, including Vermont, Massachusetts, Wyoming, Arizona, Oregon, California, Utah, Virginia and Idaho, were designated wild and scenic. The law expands wilderness designation -- which blocks nearly all development -- into areas that previously were not protected.
The law also protects land in Alaska under a contentious land swap that lets the state continue with a planned airport access road in a remote wildlife refuge near the Bering Sea. Critics call the project a "road to nowhere."
Environmental groups and lawmakers in both parties said the law will strengthen the national park system, restore national forests, preserve wild and scenic rivers, protect battlefields and restore balance to the management of public lands.
Opponents, mostly Republicans, have called the legislation a "land grab" that would block energy development on vast swaths of federal land.
Mike Matz, executive director of the Campaign for America's Wilderness, said the new law is a remarkable achievement. The largest acreage protected is in California, where three separate measures will preserve more than 700,000 acres as wilderness and designate 73 miles of wild and scenic rivers.
The largest single parcel is in Idaho, where about 517,000 acres in the rugged Owyhee Canyonlands in southwestern Idaho will be protected.
"The depth of support for this law by people from all walks of life, as well as the size, scope and diversity of the lands protected, are a clear indication Americans recognize that our wild lands must and do serve many purposes -- not the least of which is as a place to hunt, fish, hike, camp, watch birds and just find solitude," Matz said.