A swim platform makes an excellent addition to any pond or swimming hole. Using materials that have been treated against water will ensure a long-lasting platform. The size of the platform will depend on several factors like your budget. Float barrels can be found at most hardware stores or pool supply stores. The heavier the platform, the bigger the barrels you will need to use. Putting a cover like AstroTurf will soften the sitting surface and help protect the wood.