Pond Boss Forums INTRO Questions & Observations Should I bury the rim of my pond liner like this?

Yes, bury the liner. Typical pond liners are thick - 20 mil up to 60 mil. 1.5mm = 60 mil so if your liner is actually 1.5mm thick, you have a heavy duty liner. If you are making a pond just to hold water, then they don't need to be buried, but be aware that they will get brittle and degrade due to UV exposure. Without burying the liner under 15-30 cm of dirt, you probably will have to clean out the muck and organics that accumulate in the bottom annually.

Burying the liner will allow plants to grow, and they will act as a biological filter so you won't have to clean out the pond annually.

Your idea is what I would do. BUT keeping that clay in that shape will be difficult. Could you put rectangular blocks there to make up the vertical surface vs. clay? The clay will migrate to the pond.....Or make the vertical "wall" out of concrete that is reinforced by wire (like chicken wire).