GRAND HAVEN, MI -- In the aftermath of the Lake Michigan drownings of a kayaker here and two swimmers in Gary, Ind. Saturday, the Great Lakes Surf Rescue Project has ramped up its plea: If you are going out onto one of the Great Lakes, wear a life preserver.

"These things are so heartbreaking because they are so preventable," said Bob Pratt, director of education for Great Lakes Surf Rescue Project.

Of 478 drownings the group has tracked since 2010, only four were wearing life jackets, Pratt said.

"If you have a life jacket on, your chances of drowning in one of the Great Lakes is almost zero, it's less than 1 percent," Pratt said.

"If we could get all boaters, kayakers and poor swimmers in life jackets," he said, drownings would be greatly reduced.

Neither the kayaker who drowned after capsizing July 9, nor the man kayaking with him who made it to shore, wore flotation devices, the survivor told police.

Pratt said life preservers were not in use in Lake Michigan drownings near Gary, either. Three others were rescued along Indiana Lake Michigan beaches, according to a story about the drownings in the Chicago Tribune.

Lake Michigan beaches were under a hazardous conditions warning Saturday, and a small craft advisory was in effect as well.

"We had issued a statement the night before talking about the possibility of dangerous waves on the lakes Saturday," Pratt said.

"Waves have already started to pick up on Lake Michigan," the group posted on its Facebook page early Saturday morning. "It will be a dangerous day on the Lakes. PLEASE put your kids in life jackets. Stay within your ability.

Respect the power of the Lakes!"

Pratt said people are quick to underestimate the power of the Great Lakes, and to over-estimate their own abilities. He said with no buoyancy provided by salt water, and waves that come twice or three times more frequently than ocean waves-- every four to five seconds-- the Great Lakes can be more treacherous than oceans are.

Although staying clear of the water when warnings are in place is the best line of defense, Pratt said people who have driven to the beach on a day off may be determined to go ahead with their plans, in spite of conditions and warnings.

A life jacket in those cases should be a must, he said.

He also advised that everyone familiarize themselves with the strategy of "flip, float and follow" for escaping water dangers. "First flip over on your back, which allows you to breathe and see approaching waves," Pratt said. "Then float, to conserve energy and calm panic. Then follow a safe path to shore."

When paired with a life jacket, that strategy will keep swimmers and capsized boaters alive long enough for help to arrive, Pratt said.

Rosemary Parker is a reporter for MLive. Contact her at rparker3@mlive.com.