To build a backyard waterfall, create a pond, install a submersible pump, and create a waterfall and spillways. Making necessary adjustments and testing the waterfall complete this process.
Start by locating a suitable site for the backyard, clear the site of any objects and level the surface that fits the pond liner. Set the liner over the leveled surface upside down, and trace the edges of the liner with a shovel to draw a circle on the ground. Remove the liner, and dig a hole in the circle so the hole's depth suits the liner. Lay and level a layer of sand at the bottom of the hole, lay in the liner and even out the liner with a level.
To build the pump, put a plastic bin where the waterfall starts, and place in the submersible pump so that the pump is centered in the bin. Then connect a vinyl tubing to the outflow valve. Using a chicken wire, run the tubing through the holes, pour water into the bin and try out the pump operation.
After testing the pump, create the main waterfall spillway using big, flat rocks. Balance the large rocks with smaller ones, and cover the back of the bin with smaller rocks. Attach the tubing to the spillway top. Set small rocks on top of the tubing, and create spillways with smaller rocks.