As the region heads into Memorial Day weekend, Metro cautions that the water temperature of the Wild and Scenic Sandy River at Oxbow Regional Park is 46 degrees Fahrenheit (8 degrees Celsius).
That’s cold enough to induce “cold shock,” a phenomenon in which sudden immersion in cold water causes the body to gasp, hyperventilate, lose motor control, and potentially drown.
Body heat can be lost four times as quickly in cold water as it is in cold air. Cold shock can be just as severe and dangerous from water temperatures of 50-60ºF (10-15ºC) as it is from water at 35ºF (2ºC). In addition to the symptoms listed above, cold shock can induce a sudden spike in heart rate and blood pressure, leading to heart failure and stroke in vulnerable people.
“People don’t always realize that even when the air has warmed up, the glacier-fed rivers around here can still be dangerously cold,” said Metro Parks and Nature director Jon Blasher. “That’s why it’s so important to understand the risks of natural water and to take proper safety precautions.”
Even when water temperatures warm up later in the summer, lakes and rivers have hazards like hidden snags, strong currents, and sudden drop-offs. Whether you’re boating, floating, or just splashing around, remember these safety tips:
- Wear a life jacket
- Enter natural water cautiously and feet-first
- Keep a close eye on children in or around water
- Swim with a buddy
- Boat and swim sober
During the summer, Metro Parks and Nature stocks life jackets that visitors can borrow for free at all of its boat ramps and parks with water access.
Learn more about water safety