Pond Boss Forums INTRO Questions & Observations Help with Leaky New Pond

If you go the liner route, it's got to end above the high water line, it won't work if it's just on the bottom. If it accidentally gets a hole, then it might not hold water. I'd go with clay, like Leo said, 18", but I'd opt for 24" packed with a sheepsfoot roller, in 6" lifts, not packed with tracks on a dozer.