BOAT-COMPARATOR Guide

Swimming from the boat: the safety rules at anchor

Engine off, ladder down before anyone jumps, a watchkeeper on board: the simple rules that keep swimming at anchor as safe as it is glorious.

Swimming at anchor is the real reason people rent boats: that turquoise water away from the beaches, all to your own crew. It's also the moment of the day when most serious leisure-boating accidents happen — not because the sea is dangerous there, but because everyone's guard is down. Five simple rules keep the best part without the worst.

Rule 1: engine off — not "in neutral", off

Nobody gets in the water while the engine is running, even out of gear. A propeller can engage by accident (a knee against the throttle, a passenger grabbing for balance), and propeller wounds are among the worst in recreational boating: the reference study by R. J. Mann published in 1980 in The American Journal of Sports Medicine (see the study on Google Scholar) documents multiple, deep, parallel lacerations, mostly to the limbs, with amputations in severe cases. Cutting the engine removes that risk entirely — and it only restarts once everyone is back aboard and counted.

Rule 2: ladder in the water before the first dive

The freeboard of a modern boat, even a small one, is nearly impossible to climb from the water. Fold the swim ladder down before anyone jumps, and check it can be used from the water. It's the summer version of the reflex described in our man overboard guide: a swimmer who can't get back aboard is a swimmer in trouble, even ten metres from the boat.

Rule 3: someone always stays on board

A "swim watchkeeper" who isn't swimming: they count heads, watch the drift and can manoeuvre if needed. A boat at anchor is not stationary — it swings around its anchor with the wind and can move astern faster than a tired swimmer can follow. In a fresh breeze, stream a floating line from the stern (a swimmer's "lifeline"): anyone caught out by the current has something to grab. And if the anchor starts dragging mid-swim, the watchkeeper applies our guide to a dragging anchor — one more reason they should know where the windlass control is.

Rule 4: pick the right place to swim

You don't swim in a channel, near a busy harbour entrance, or in the middle of a tightly packed anchorage — an arriving RIB cannot see a head between hulls. Anchor at the edge of the field, clear of the traffic; inside the 300-metre band boats are limited to 5 knots precisely to protect swimmers, but don't stake your life on it. Our guide to anchoring properly helps you pick the spot that protects both your anchor and your swimmers — and if children are heading ashore, the dinghy and beach landing guide completes the picture.

Rule 5: lifejackets, children, alcohol — the obvious things forgotten at 30 °C

Buoyancy aid or lifejacket for children and unsure swimmers, including for "just a paddle by the ladder"; no head-first diving into water whose depth you haven't checked; and the apéritif after the last swim — our guide to alcohol, fatigue, wind and sun explains why those four add up faster at sea than ashore. For towed toys and snorkelling, the specific rules are in our guide to paddleboards, snorkelling and water toys.

If some of your crew can't swim, the swim stop needs different planning — our guide to renting a boat when you can't swim is written for them. And to find that perfect calm anchorage, compare the offers at your destination: Boat-Comparator queries Boataround, SamBoat and Click&Boat live for every port.

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