WASHINGTON (Reuters) - The Senate on Thursday approved a sweeping conservation measure as it tries to reverse years of rollbacks in environmental protection by the administration of outgoing President George W. Bush.

A day hiker leaps over the Gooseberry River downstream of the State Highway 61 bridge that spans the river, north of Duluth, Minnesota, August 5, 2007. REUTERS/Eric Miller

On a vote of 73-21, it passed a package of nearly 170 land and water bills and sent it to the House of Representatives, which was expected to give it final approval.

Barack Obama is set to sign it into law after he is sworn in as president on Tuesday, one of the first moves in what is likely to be a more aggressive approach toward the environment.

The Senate-passed measure would protect millions of acres (hectares) of America’s parks, rivers, streams and trails from development.

Critics accused Bush of slowing down efforts at wilderness designation, easing environmental regulations and declining to address global warming.

A centerpiece of the Senate package is the National Landscape Conservation System Act. It would make permanent a 26 million-acre (10.5 million-hectare) system composed of the U.S. Bureau of Land Management’s best lands and waters.

“Congressional recognition of the National Landscape Conservation System is long overdue and very much worth celebrating,” said William Meadows, president of The Wilderness Society.

Richard Moe, president of the National Trust for Historic Preservation, a nonprofit group, said, “The national monuments, wilderness areas, scenic rivers, trails, and historic sites that make up the National Landscape Conservation System have correctly been called BLM’s ‘crown jewels.’”

Senate Majority Leader Harry Reid, a Nevada Democrat, said the legislation, crafted by members of both parties, “will protect and improve America by land and by sea.”

There was some discontent in the Democratic-led Senate among Republicans who were refused a chance to offer amendments. Democratic pushed for passage after months of Republican delays.

“As we begin the new Congress, it’s apparent that its business as usual for the Democratic majority and the so-called change coming to D.C. is only in words, not action,” said Sen. Jim Inhofe, an Oklahoma Republican.

Democratic Sen. Jeff Bingaman of New Mexico called it one of the broadest conservation measures in decades. Mostly Republican critics, however, said it would deny access to lands for possible oil and gas drilling.

The measure would designate as wilderness more than 2 million acres in nine states -- from Virginia to California -- and declare former President Bill Clinton’s boyhood home in Hope, Arkansas, a national historic site.