Kayakers, canoeists and paddleboarders on the Brandywine must wear a U.S. Coast Guard-approved life jacket through April 30, 2027, under Pennsylvania's seasonal cold-weather mandate.

The requirement took effect Sunday, Nov. 1, the Pennsylvania Fish and Boat Commission (PFBC) announced. It covers anyone aboard a boat less than 16 feet long and anyone using a kayak, canoe or paddleboard, regardless of the craft's length, on all Pennsylvania waters. Life jackets must be worn while the vessel is underway or at anchor, according to MyChesCo.

Water temperatures can stay dangerously low through early spring, even on warm days. Cold-water immersion triggers an involuntary gasp reflex that can cause a person to inhale water immediately after falling in, according to the PFBC. The reaction can also produce panic and an impaired ability to swim.

Pennsylvania boating accident reports show nearly 80% of all boating fatalities occurred because boaters were not wearing life jackets, the commission reported. The PFBC also reported a significant reduction in cold-weather fatalities since the mandatory law was enacted in 2012.

The Brandywine Conservancy's water safety guidance advises paddlers to track their location using landmarks such as road crossings and bridges, noting that cell coverage is unreliable along some stretches of the river.

In an emergency on the water, call 911 and provide your launch point and how long you have been on the water.