How to Build a Pond or Water Garden in Your Yard

Move the liner aside and begin digging out the area. Dig a couple of inches wider than the actual shape of your pond and 3 inches deeper than the liner. You’ll need this space to allow for a layer of sand to act as a base for the shell. The liner we’re using for this pond is 18 inches deep so we’re digging down to 21 inches. Remove roots and rocks as you dig, and keep the hole as level as possible.

Place the liner in the hole. At this point, the top edge of the liner needs to be flush with the ground and level. Check by laying a straight 2 by 4 on edge across the liner and placing a level on the board. If one side is low, use sand to build it up to the right level. Also use the 2 by 4 to make sure the lip of the liner is level with the ground.

Remove the liner and add about 3 inches of sand to the bottom of the hole to raise the edge of the pond a couple of inches above the ground. This keeps runoff from getting into the pool and making the water cloudy and dirty. Sand will let you make a smooth, solid base for the liner.

Level out the sand with the back of a garden rake. Check for level and place the liner on the sand.

Place the 2 by 4 across the liner to make sure you have a 2- to 3-inch gap between the liner and the ground. In addition to helping keep runoff out of the pond, this gap will allow space for the landscaping and stones that we’ll use as part of the landscaping around the pond.

Place the level on the 2 by 4 and ensure the liner is level. Leave the 2 by 4 and level in place, and pour sand into the hole to begin backfilling around the shell. The sand should fill in all the gaps, nooks and crannies, and support the sides of the pond shell and help keep it level as you build the second tier for the waterfall. Check for level as you work.

Add a thin layer of sand. The sand needs to be level left to right but tilted down a bit from the back to the front so the water will flow down into the pond.

We’re using flexible pond liner for the waterfall, so we’ll be able to cut it and shape it. Place the liner across the area you built up for the waterfall, and make sure the edge drapes down into the pond. You’ll hide the overlapping liner when you add decorative rock to the waterfall.

Use a utility knife to cut and shape the liner to fit, but leave it larger than the area you need to cover. If you trim away too much, you won’t have as many options to shape it. You can trim it to the exact size you need later.

Dig a hole to about half the height of the filter. You need to be able to access the top of the filter, but you want to hide as much of it as possible. Dig a trench to allow the pond tubing to run below the surface.

Use a hose clamp to secure one end of flexible pond tubing to the pump outlet. Run the tubing to the inlet on the filter. Cut the tubing to length with a utility knife and use a pipe clamp to attach it to the filter inlet. Run another length of tubing from the outlet on the filter to the top of the waterfall.

Run the hose up to the waterfall and cut to length as needed. We’ll use a bricklayer’s hammer to break a flagstone into two pieces, hide the hose between the pieces and use spray foam to secure it in place. Then we’ll place another piece of flagstone to cover the hose.

Place the pieces of flagstone around the edges of the pond shell. Again, use the beach pebbles, egg rock and pea gravel to fill in gaps, hide the liner and dress up the area around the pond as needed. As you work, dirt, gravel and stones will accumulate in the bottom of the pond. Clean out as much as you can, and wipe down the liner to keep the debris from clouding the water.

Using flagstone pieces, build a small shelf to hide the pump and give the pond a more natural look. Add pea gravel to cover the ledges on the pond shell and the bottom of the shell.

Begin filling the pond using a garden hose.

Once the pond is full and the pond foam has cured, remove the hose and plug in the pump to begin circulating the water.

We’ll add water lilies to complete the look of the pond. The water lilies will help prevent algae and provide some protection for fish if you choose to add them.