How to Make a Garden Pond Waterfall | Build Your Own Backyard Feature

A garden pond waterfall is built by excavating the pond, forming an elevated waterfall mound, lining both areas with underlayment and pond liner, placing rocks to shape the water path, installing a submersible pump and tubing, then testing flow and sealing gaps with foam sealant as needed.

For the full breakdown, see our best Garden Pond Waterfall guide.

Building a garden pond waterfall breaks down into straightforward steps. This guide walks through the full build order—from selecting your spot and digging the pond to stacking the waterfall tiers, setting the pump, and tuning the flow for a natural-looking stream that doesn’t leak.

Step 1: Choose the Location and Plan the Layout

The best spot is slightly above or next to the pond. A natural slope helps, but flat ground works if you build the waterfall mound 12 to 36 inches high. Outline the pond shape with a garden hose or spray paint, and map where the waterfall will sit. Compact the ground under the mound well—loose soil will settle under the weight of water and rocks, shifting the structure. For fish ponds, plan a deeper section (at least 24–30 inches deep by 18 inches wide) as a safe zone from predators.

Step 2: Dig the Pond and Shape the Waterfall Mound

Dig the pond first, not the waterfall. Pile excavated soil where the waterfall will go to create the mound. Create an elevated 6-inch to 8-inch ledge around the pond perimeter to hide the liner edge later. Remove all debris like roots and sharp stones from the pond base and walls. Shape the waterfall mound into tiered steps—flat stones work best for each spillway. Stack cinder blocks under the mound to create stable, level tiers. For preformed liners, spread about one inch of sand beneath for leveling.

Step 3: Install the Liner System

You need underlayment and pond liner covering both the pond and waterfall mound. The liner should overlap the pond edge by at least 6 to 12 inches (some sources recommend 10 inches or more). Extend the liner up the mound and into the pond basin to reduce water loss at the seam. Underlayment overhang should be about 12 inches on all sides, including the waterfall area, to prevent rocks from puncturing the liner. Place the liner snug against the shape, and add larger rocks along the waterfall edges to hold it in place and guide the water path. Rinse all rocks before placing them.

Step 4: Set Up the Pump and Tubing

Use a submersible pump placed at the pond’s lowest point on a brick or flat stone to keep it out of muck and accessible. Run flexible tubing from the pump up to the top of the waterfall, hiding the hose under rocks or along the back of the mound. The pump must be powerful enough to push water to the top spillway—check its maximum lift height against your waterfall’s total rise. Keep the pump accessible for cleaning and winter removal. For the top spillway, tubing should empty onto the topmost flat rock so water fans out naturally.

Step 5: Test, Tune, and Seal

Fill the pond and turn on the pump. Watch the water flow—adjust individual stones to redirect the stream and hide visible gaps. This is iterative; plan to move rocks several times. Once the flow path is good, seal gaps between waterfall rocks with waterfall foam sealant. Apply it along edges where water might escape, wait about 10 minutes for the outer shell to cure, then shape it into voids. Common mistakes: not compacting the waterfall mound (causes settling), skipping underlayment (puncture risk), and skimping on liner overhang (water loss).