Pond liner underlayment increases pond liner life and makes it more puncture resistant by protecting it from sharp objects in the soil. Pond liner underlayment also stabilizes the ground under the liner to keep EPDM and other water garden liners from over-stretching. It is quick and easy to install, and unlike newspaper or sand, pond underlay resists pond settling, decomposition and shifting. Keep your water garden liners protected by purchasing 35' wide pond liner underlayment today!