Choose your site. Select an area with an existing grade change or plan to create grade changes through your excavation. Locate your waterfall near a patio or another spot where you can enjoy its beauty and sound. The waterfall should also be close enough to an electrical source for the pump. Mark out the area for the waterfall and receiving pond with stakes and string.
Choose a pond liner. Rigid preformed pond liners come in many shapes and sizes. Some actually include built-in waterfalls. Flexible pond liner allows you to create your own shape and contours.
Dig a pool to receive the water and excavate the channel where the water will flow. If you are using a preformed liner, match the depth of your excavation to the liner. If you are using flexible liner, dig at least 18 inches deep.
Prepare the bed. Remove any rocks and tamp the soil firmly using a hand tamper. A 1-inch layer of sand, cardboard, newspaper or another cushioning material will provide extra protection underneath your liner.
Install the liner. If using a rigid liner, place it in the prepared bed. If you are using flexible liner lay it in the hole and into the channel where water will flow. Allow it to form into the shape of the receiving pool and water course. Use large rocks along the edge of the liner to hold it in place. You may need to use more than one piece of flexible liner. If so, overlap the pieces by at least 6 inches.
Lay the stones. Cover the entire liner with stones using larger stones along the vertical sides of the receiving pool and channel. Lay river rock or cobble along the bottom of the pool and channel. If desired, build a structure of several large rocks for the beginning of the falls. Choose large flat rocks for the spillway, the area where the water will drop.
Check your work. Use a hose to run water from the beginning of the falls to the end. Make sure the water is flowing where desired and make any necessary adjustments.
Install the pump and tubing. Use tubing long enough to accommodate the entire water course and attach it to the pump. Place the pump in the receiving pool. Run the tubing along the outside of the water course and insert the end under one of the rocks at the beginning of the fall. Fill the receiving pond with water, turn on the pump. Bury the tubing and enjoy your new falls.