BOAT-COMPARATOR Guide

Running aground in a rental boat: what to do if you touch bottom

Hitting a sandbank or a rock with a rented boat: the first moves, when to free yourself, who to call, and why you should never hide it from the operator.

Touching bottom — with the keel, the outdrive or the rudder — is one of boating's most common incidents, and one of the most stressful in a rental: the security deposit immediately comes to mind. The good news: handled well, a grounding on sand usually ends with no damage at all. The bad news: handled badly, or hidden from the operator, it can get very expensive. Here's the drill.

Sand or rock: two very different situations

Contact with a sandbank or mud at low speed is generally benign: the boat slows, stops, the hull doesn't suffer. Contact with rock, even slow, is another matter: keel, outdrive or rudder take a point impact that can crack, bend or loosen structures — sometimes with nothing visible from deck. It's no accident that groundings are among the most studied types of maritime accident: a literature review by Mazaheri, Montewka and Kujala published in 2014 in the WMU Journal of Maritime Affairs (see the study on Google Scholar) surveys decades of research on grounding risk and highlights the decisive weight of human factors — course-keeping, lookout, preparation — in whether they happen at all.

The first moves, in order

Stop (neutral), and resist the reflex of slamming into full reverse: on rock you make the damage worse; on sand you pack the propeller and the cooling intake with sediment. Tilt up the outdrive or lift the centreboard if the boat allows it. Check the crew (a hard grounding throws passengers about), then lift the floorboards and look into the bilges: any ingress of water, however modest, changes everything — if it's there, lifejackets on everyone and an immediate call to the coastguard on channel 16. Note the time and the position: you'll need both for everything that follows.

Free yourself or wait?

On sand in calm weather, the classic manoeuvre is to heel the boat (crew on one side) and back off gently, or simply to wait for the rising tide on Atlantic coasts — our guide to tides for renters explains how to read the hour that will set you free. In the Mediterranean, with no tide to help, don't force it under engine: this is exactly the scenario where you call for help — see our guide to towing and assistance at sea for who to call and who pays. On rock, or with the slightest doubt about watertightness, don't try to carry on as if nothing happened.

Telling the operator: always, even if "it seems fine"

This is the point too many renters get wrong. A keel strike can be invisible to the naked eye and discovered weeks later — or by the next renter, who will set off on a weakened boat. Call the operator as soon as it happens: they know their boat, will tell you what to check, and will decide whether to cut the trip short. At hand-back, mention the grounding during the check-out inspection. Hiding the incident and being found out (grounding damage has a recognisable signature) exposes you to a dispute far heavier than the excess — our guide to withheld deposits covers those situations.

Deposit, excess, insurance: what to expect

Grounding damage falls under the boat's deposit and insurance: your maximum exposure is normally the excess, not the full repair — unless there's a characterised fault (sailing in an area explicitly excluded by the contract, for instance). If you're cruising rocky waters — Brittany, Croatia, Greece — excess waiver insurance pays for itself quickly.

Avoiding it: three habits

Keep the chart in front of your eyes rather than in the back of your mind, treat shoaling water near beaches and channel entrances with suspicion, and set your depth alarm sensibly (2 m under the keel, not 0.5). Modern navigation apps overlay your track on the chart: a glance every couple of minutes is enough.

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