Protecting water in the Great Lakes may cause Michigan to make concessions in its water use.

According to testimony heard this week before the Michigan Senate Natural Resources and Environmental Affairs Committee, lawmakers may need to enact water-use laws for the state to have a solid legal defense against water diversion challenges from other states.

The committee met Tuesday to discuss Annex 2001, the proposed changes to the Great Lakes Charter of 1985. Governors of eight Great Lakes states, including Gov. John Engler, and the premiers of Ontario and Quebec want to establish regulation for water diversion by 2004.

Tracy Mehan, director of Michigan’s Office of the Great Lakes, testified to the committee under international trade agreements, like NAFTA and GATT, and the Constitution’s interstate commerce clause, Michigan’s bans against water diversion would likely be deemed illegal if challenged.

“Any standard has to be applied evenhandedly,” Mehan said. “You can’t discriminate against diversion outside the basin but let it go inside the basin.”

Mehan said Michigan must implement the same consumption standards it expects others states to meet. Michigan’s water use is not subject to regulation by other states because the state is entirely within the water basin.

“We advocate a common standard tied to conservation and resource improvement,” Mehan said.

Committee chairman and state Sen. Ken Sikkema, R-Grandville, said the Legislature needs to proceed cautiously before changing state law to meet the requirements that have not been legally challenged in the past.

“It is not worth putting our water resources at risk to test that theory if there is another way we can do it that is protective of the Great Lakes,” Sikkema said.

Sikkema said the Legislature does not want to lose control of Michigan’s water if they do not comply with the accord.

Minority vice-chairman and state Sen. Gary Peters, D-Bloomfield Twp., said scientific data is needed to determine the detrimental effects of diversion on the Great Lakes.

“My concern is that we are moving away from the moratorium on diversion because we lack data,” Peters said.

If diversion increased significantly there could be an environmental impact, said Ken Silfven, spokesman for the Michigan Department of Environmental Quality.

“You could see loss of water in wetlands. There could be navigation problems for shipping and recreational boaters,” he said.

Silfven said those are the worst-case scenarios, but population growth in the South and West of the United States and diminishing aquafiers in the Plains means demands for fresh water could increase in the future.