Canyoncreek in the past conversation on islands a year or so ago on pond boss I have a complete description and pictures of how I built this island. The whole thing cost about $60. Basically is is built of 2" x 4' x 8' close cell building foam, pink or blue, you can buy at any big box store. Close cell foam will not absorb water. My first island has been in the water for 4 years. The cover on top of the foam is a walmart black rug made in Equipt and is quite rugged. Holding the rug to the foam is Gorilla Glue plus 4 bolts for extra rug attachment. It is anchored with parachute cord attached to one corner of the rug and to a boat anchor.
You will find the island building in this link.
http://forums.pondboss.com/ubbthreads.php?ubb=showflat&Number=432623&page=1Visitors to the island.
