Elastoplast waterproof strips are a strong bandaid that stays on and is also protected from water.A brilliant brand to buy for all sorts of bandaids.

Elastoplast have a good range of fabric strips for all sorts of cuts and abrasions. We like to have a good supply and variety of fabric strips in the first aid kit, including these ones which work well.

It’s not entirely waterproof when I used it some time ago. But it covers the wound and stops the nasties getting into it which is what you’re after