When you head to the beach or pool with a baby, your natural reaction is probably to grab a pack of disposable swim nappies. But they absorb little to nothing, so what's the point? A reusable swim nappy makes a lot more sense.
This adorable swim diaper comes from Bummis Cloth Diapering. I also have one just like it that I made myself. Mine has raccoons.
Neither one will keep pee out of the water; they're not designed to. Their job is to keep poop from leaking out into the pool, and both do an OK job of it. Reusable swim nappies are made of a mostly-waterproof fabric, and they Velcro on like a regular nappy. If the kid poops, the poop is contained; you just have to dump the poop and rinse out the nappy.
With a disposable, you can throw the nappy out and grab a new one, thereby saving yourself about 30 seconds worth of effort -- and that's the end of its advantages. You need to keep buying the disposables, and keep an eye on the supply to make sure you don't run out. On the other hand, you can keep a reusable swim nappy with the kid's swimsuit, washing and wearing them together.
A reusable swim nappy costs $17.60 from Baby BeeHinds, which is only $7 more than the $11 Woolworths is charging for a package of 12 disposables. The reusable is cheaper in the long run, and more convenient. Come on, how often does that happen? Consider buying yourself (or the parent in your life) a reusable, but also double check your pool's rules: Some only allow one type or the other.