Motorized recreation in America's national parks long has been a controversial topic, with groups that back snowmobiles, personal watercraft, all-terrain and off-road vehicles maintaining they have a right to head to the parks with their machines to play. Many conservation groups, however, point to these uses as inappropriate because of their noise and pollution and the resource damage they can inflict.

Today, in an action sure to inflame some national park visitors, Friends of the Earth and The Wilderness Society sued the National Park Service to reinstate bans against personal watercraft at Gulf Islands National Seashore and Pictured Rocks National Lakeshore.

Just eight years ago the National Park Service concluded that Jet ski use was a “controversial, recreational” activity and inappropriate in most areas of the National Park System. The agency deemed Jet skis, aka personal watercraft, “high performance vessels designed for speed and maneuverability and are often used to perform stunt-like maneuvers.”

When the Park Service back then to ban PWCs from Gulf Islands, it said in part that “PWC use poses considerable threats to estuarine flora and fauna, pollutes waters essential to estuarine and marine health, poses unacceptable risks of injury to operators and bystanders, and conflicts with the majority of other longstanding uses of the Seashore.”

And yet, in 2006 the Park Service changed course and began finalizing regulations to allow the water toys back into these park units.

According to TWS and Friends of Earth, these reversals violate both the 2006 Park Service Management Policies and a settlement agreement reached in 2001 by the Park Service and Bluewater Network, which is a division of Friends of the Earth.

“The decisions to re-open Gulf Islands and Pictured Rocks to Jet skis appear to be based on politics, not sound science,” said Danielle Fugere of Friends of the Earth. “Eight years ago, the Park Service concluded that Jet skis are dangerous and cause environmental harm, yet, without any new evidence, the Park Service changed course to allow jet skis back into these sensitive parks. "

Over at The Wilderness Society, Kristen Brengel says "the National Park Service has lost sight of its mission. The agency should have upheld its mission the conserve park resources and restored the protections for Pictured Rocks and Gulf Islands by reinstating the prohibitions on jet skis. We need to make sure the Interior Department and National Park Service serves the American public by ensuring these places are safe and protected.”

Both Interior Secretary Dirk Kempthorne and National Park Service Director Mary Bomar have said that science will guide agency decisions, and yet that doesn't seem to be the case in PWC-related matters nor, for that matter, in snowmobiling in Yellowstone National Park..

Here are some of their words from 2006, voiced when the Park Service launched its Centennial Initiative:

* Stewardship and science will guide decisions, Mr. Kempthorne said in his cover letter regarding the Centennial Initiative to the president. An inventory of all wildlife in parks will be completed, a vital baseline to monitor change and adjust management. Strategic acquisitions will protect landscapes.

* Much has been accomplished and more remains to be done to fulfill a common American dream -- to leave things better for those who follow us, added Ms. Bomar in her own letter.

* This is not only a report to the president, but a pledge to the American people, who are the shareholders in the greatest system of parks and special places in the world ... a pledge that the men and women of the National Park Service will continue in preserving these wonderful places for the generations yet to come, Ms. Bomar added a bit later.