Great Lakes governors have tightened their plan to regulate water diversions, hoping to lure Canadian and environmental support for an international agreement.

The revised plan, unveiled Thursday, tightens the spigot on the governors' original water use plan announced last summer.

The changes were made after thousands of comments said the original plan didn't go far enough to stop diversions out of the region or to promote water conservation within the region.

While last year's version only limited diversions out of the region, the new version effectively bans diversions, with limited exceptions.

The new plan also calls for the eight Great Lakes states and two Canadian provinces to adopt common standards governing water use within the states and increases commitments to reduce water use and bolster conservation in the Great Lakes watershed. It further recognizes tribal rights and involvement.

The plan allows exceptions for diversion to communities outside the Great Lakes watershed but within counties that lie at least partly in the Great Lakes basin.

Emily Green, director of the Sierra Club's Great Lakes Program, said her group has suggested additional changes but that the revised version is much better than last year's.

"This version is effectively a prohibition on diversions while last year's version set out steps on how water could be diverted. And this version has a lot more emphasis on responsible water use and conservation," Green said.

"Communities not far outside the region already are experiencing water shortages and water quality problem because they didn't live within their means. We don't want that to happen here," Green said. "And we don't want to have to send water to places that didn't live within their means. We shouldn't ever send water so there can be golf courses in the desert."

Wisconsin Gov. Jim Doyle, co-chairman of the Council of Great Lakes Governors, said in a statement releasing the plan that it was tightened to accommodate Great Lakes region residents who consider the lakes a special resource to protect. "... their voices have been heard loud and clear," Doyle said.

But others said the new version still doesn't go far enough to protect water from being taken out of the region. Melissa Scanlon, director of Madison-based Midwest Environmental Advocates, said one little-known provision in the draft agreement with Canadian provinces makes an exception allowing unlimited diversions of bottled water.

"It's a terrible precedent to treat bottled water differently," she said. "This provision is buried and we don't think a lot of people are going to notice it. But it needs to be dropped."

After reaching accord on the principles of a water-protection plan in 2001 -- the so-called Annex 2001 agreements -- the Council of Great Lakes Governors last summer released a blueprint for putting the plan to work as an interstate compact, and as an international agreement with Canadian provinces that border the lakes.

The original draft didn't prohibit diversions, but imposed limits on diversions outside the Great Lakes basin. It still allowed projects to pump more than 1 million gallons per day out of the region with some restrictions.

After several public hearings, including one in Duluth in October, plus 10,000 written comments, it was clear to the governors that their plan needed work. The original draft was doomed when officials from Quebec, Ontario and the Canadian federal government said it lacked adequate protections. Several American Indian tribal leaders also panned the agreement, saying they hadn't been given enough input.

The new version could be reworked again after the 60-day public comment period. Eventually, a final version will be sent for all eight governors and two provincial premiers to sign.

Even then, however, the water plan will be far from law. To make it a viable interstate compact, all eight state legislatures must approve the deal -- without amendment -- and then it must pass Congress, also without changes. That could be well into 2006, or later, if at all.

To become a truly international agreement, Ontario and Quebec officials also must sign on.