With hot weather ahead, residents should think twice before dipping into the dangerously cold waters in this area.

Last Saturday, a young boy drowned in Lewis County, and two men are still missing after floating down the Green River.

Each year, King County residents die when they venture into these waters without appropriate lifesaving gear and lifeguard protection. In late spring, even as the weather warms up, King County lakes and Puget Sound are still extremely cold, and snowpack melt feeds rivers that are running deep, cold and swift. Public Health is urging all residents to use extreme precaution in activities around open water.

“No matter what the outside temperature reads, late spring is not a good time to be swimming in local rivers, lakes or in the Sound,” said Dr. David Fleming, director and health officer for Public Health — Seattle and King County. “Even the best swimmers with lifejackets are at risk for serious trouble in the cold water.”

In 2007, there were 24 unintentional drowning deaths in King County. Fifteen of the drownings took place in open water such as rivers, lakes, or Puget Sound. Six of them — 25 percent of the yearly total — took place during the months of May and June, when waters are still very cold from winter runoff.

Lakes and rivers are particularly dangerous before summer. Beaches do not have lifeguards yet and rivers are colder, swifter and more hazardous in general than later in the summer. Stay out of local lakes until lifeguards are in place in mid-June; for spring swimming, choose a pool that has lifeguards.

“River systems are not only extremely cold this time of year; they are constantly changing and may have new pieces of wood either submerged or spanning river channels that can present serious dangers,” said Theresa Jennings, director for the King County Department of Natural Resources and Parks. “Rivers will be running high and swift from snow melt. Swimming is not a good idea in these conditions, and people should exercise great caution when navigating or doing recreational activities on the river.”

Kayakers, rafters and other boaters should stay away from rivers unless they are highly experienced, or should sign up with professional touring companies. Professionals will know the river and be aware of common locations where treacherous logjams are located at this time of year.

In addition, children should never boat or float a river without the close supervision of an adult. River boaters should know and practice river rescue techniques, and be trained in rescue skills, CPR, and first aid with emphasis on recognizing and treating hypothermia.