ST. PAUL, Minn. - Boats will be hitting the water all across Minnesota during the coming 4th of July week, and with the invasion comes a warning:

Slow down.

The Minnesota DNR says water levels on a number of Minnesota lakes and rivers are expected to remain high through the holiday weekend, so boaters are being advised to slow down and use caution.

"People should always wear their lifejackets while boating, but especially during times like this," said Tim Smalley, DNR boating safety specialist. "The waters are higher and moving faster than people are accustomed to, and that can create dangerous situations."

High water conditions on the Mississippi, Minnesota and Lower St. Croix rivers can bring special hazards to recreational boaters.    

"River and lake debris could include trees as well as man-made items," Smalley advised. "Debris will often float just at or below the surface, so a boat traveling at high speed may not be able avoid it in time. Hitting a deadhead or snag at high speed could result in anything from a broken propeller to a ruined lower unit or worse; serious injuries to boat occupants."

High water levels can also wreak havoc on lakeshore property when boaters don't keep their speeds and wakes down. Under both state and federal law, boat owners are legally responsible for their wakes.

"During high water on a river, boat waves are not dissipated by the gentle slope of a beach but instead slam directly into the steep face of the bank," explained Scot Johnson, Mississippi River hydrologist for the DNR. "Much of the energy contained in the wave is conveyed to the bank. This contributes to an accelerated rate of bank erosion."

A 1992 Mississippi River study by the DNR near Red Wing showed that during high water, a large wake (25 inches high) from a cruiser or houseboat can be 30 times more destructive then a smaller 5-inch wake.

Boaters can reduce wave impacts by:

• Limiting boating activity on rivers until water levels return to normal summer conditions.
• Maintaining slow no-wake speeds (less than 5 mph) during high water.
• Staying close to the center line of the river. This will allow some wave energy to be dissipated as it travels through the water.
• If speeds greater than 5 mph are absolutely necessary, accelerate to planing speed as quickly as possible and stay on plane until reaching destination.
• If houseboat or cabin cruiser does not have a planing hull design or adequate horsepower, maintain slow no-wake speeds until water levels return to normal summer conditions.

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