Building a stream, do I need to put anything under the liner?

[addy1]

Addy, did you use an 8oz geofabric?

No in the pond I used carpet underlay. The stream just two layers of liner.

My liner is not epdm.

I did have a deer fall into the pond twice, once through the ice, once stuck under the net. Both times those sharp lil hooves made all sort of marks trying to get out, no tears.

Both lived.

We are shale with a bit of dirt.