Pond Boss Forums POND CONSTRUCTION Renovating a Pond or Lake? Pond questions

I think that you need to identify where the pond is leaking from. Since the pond drains down, your source water needs to come from run-off (watershed) or a well (or other pumped-in source). Therefore, the bottom must be sealed up like a tub (no gaps to a permeable soil layer). You need a continues liner of water-impermeable material. If you take soil samples from various areas around your pond bottom and submerged sides, then you should be able to determine how much of the area is suitable for holding water, or if the whole bottom needs to be lined. The permeable area can be lined with compacted clay, or the whole pond area could be lined with a synthetic liner. If you have the budget, you may be best to call in an experienced pond builder to suggest your most cost-effective solution. A best-case would be that only the deep hole needs to be sealed (and joined to the rest of an existing impermeable lining).