How to Build a Backyard Waterfall in Lancaster County, PA

Backyard Waterfall installed by Eshelman Mill Gardens Landscapes Inc.

You can easily build your own backyard waterfall to add interest to your yard. The process isn’t very difficult and can be achieved with little expense.

We’re big fans of the backyard waterfall garden, so here’s a step-by-step guide to building your own waterfall right in your own backyard!

Busy? Pin this to your Pinterest board for later.

Shopping for a Backyard Waterfall

First, gather your supplies. Most of these can be found at hardware stores or discount DIY stores, like Lowe’s or Home Depot. Here’s what you’ll need:

25-30 rocks of various sizes. Try to get some large flat ones too.
Submersible pump.
Tubing to run from pump to top of waterfall.
Large ceramic flower pot (or similar) to house tubing about 11 inches tall.
Rigid pond liner.
Carpenter’s level.
Shovel.
Sand.
Garden hose.

Prepping for a Backyard Waterfall

Your backyard waterfall will run on electricity, so it will need to have its own outlet for a power source. Ideally, the the waterfall should be located close to a patio, deck, or porch. If you don’t have an outdoor outlet, one will have to be installed by a certified electrician.

Remove all weeds in the area where you will be digging your pond. Make sure the area is level. Then measure the liner you have chosen so you can dig a hole big enough to hold it. Simply invert the liner and trace around it on the ground. (Mark the outline with flour or white spray paint.) Then start digging!

The depth of the hole should be the same depth as the liner and the diameter as close to the actual diameter of the liner as possible to ensure a nice, snug fit. If you find the hole you’re digging is a little bigger than the liner, just fill in the sides with sand.

Sand will also be used at the bottom of the hole, because sand floors provide the stability needed to play with the height of preformed liners. Put about an inch of sand at the bottom of the hole, so that the top rim of the preformed liner will stand about an inch above ground level. That will reduce the amount of dirt that will fall into your pond. Rake the sand to get the level of the preformed liner just right.

Installing the Backyard Waterfall

Next, place the preformed liner into the hole for the backyard pond. Make sure it is level — front to back, and left to right. If your carpenter’s level is showing that the bottom of the hole (where the sand is) is not level, then remove the preformed liner from the hole and rake the sand until it is level. Now, it’s time to move on to the structure itself.

Take a look at the rocks you have. The most important rocks are what might be termed the “spillway” rocks. These are the rocks that will make up the waterfall itself. The spillway rocks should be relatively flat as opposed to rocks that are more rounded in shape. They should also have sharp, squared edges; water will cascade more cleanly over sharp edges. When rocks have blunt, gently-curving edges, some of the water tends to follow that curve and trickle back under the rocks.

Try to choose rocks that are most likely to channel the falling water in the precise direction in which you want it to go. How you lay the spillway rocks is also important. In addition to seeking out relatively flat rocks with sharp edges, see if you can find rocks that are slightly concave or cupped. Occasionally, you’ll find rocks that curl up ever so slightly at the edges, leaving a depression in the middle. The natural channel in such rocks will be very advantageous for the creation of the spillways in your cascade design. Their raised edges will help keep the water from deviating where you don’t want it go, namely, behind the rocks.

You’ll essentially be building four mini rock walls around the pond. Make a small trench in the rock walls for the tubing to sit in under the rocks, so that the rocks won’t smash the tubing. This will keep the tubing free, so that you can slide it through the pot up or down, at will. It also gives you the leeway that you need, since you won’t know exactly from what height you’ll want the water to fall until you’ve finished laying the rocks.

Speaking of the flower pot, you’ll need that ceramic pot about 11 inches high and with a drainage hole in the bottom that’s big enough to fit the diameter of your tubing. The pot functions as housing for the tubing within the cascading structure for the waterfall. You could easily substitute something else that might work better and can use either a Terra cotta pot or a plastic one. The pot will protect the tubing while you lay rocks all around it. The pot, and the tubing inside, won’t show when you’re finished. It should be hidden at the center of your rock work.

After laying a first course of rocks in the front, cover them with a sheet of black plastic. Extend one end of the plastic up to the top of the plastic pot, while tucking the other over the lip of the preformed pond liner and down into the water. Then disguise the plastic with rocks, so that it won’t be visible in the pond. The plastic will catch and funnel more water than the rocks alone could. Without the plastic, you’ll lose a lot of water when it splashes onto the rocks.

Now, lay one long, flat rock across the rest and rest it right on top of that plastic. The long, flat rock juts out in the direction of the pond, forming an overhang. It will serve as a shelf for your first spillway rock, so it will be referred to as the “shelf rock.” Invert the flower pot and thread your tubing through the hole in its bottom. Place the pot on the ground (still inverted) at the center of what will be the rock waterfall structure.

How far in back of the pond should this be? That depends on the depth of your rocks. You’ll want the rocks that face the pond to abut it; if possible, they should even overhang the pond slightly. So if the rocks you’ll be using there are 8″ in depth (i.e., front to back), the front side of the pot should be about 8″ back from the edge of the pond.

How long should the tubing be? Leave yourself with a length that is longer than what you’ll need, and trim later as necessary. This will make your job a lot easier. Run the tubing either to the left or the right side of the pond and rock waterfall. As a cosmetic touch at the end of the project, you can go back and hide it with stones and/or mulch. Be sure to stagger the seams of the rocks, in a brick pattern, for a better aesthetic.

Place your first spillway rock on the shelf rock, in such a way that the spillway rock overhangs the pond even further. Continue laying the four walls, until you’ve reached the height you desire. Once you’re done encasing the pot with rock walls, you need to place two longer stones across the top (either front-to-back or left-to-right) to span the walls. Pull up the tubing to gain more length, if necessary, and gently sandwich the tubing in between these two longer rocks to hold it in place.

Begin trying to position your first spillway rock on top of your shelf rock. It should jut out over the pond even further than the shelf rock. Elevate the first spillway rock in the back, to achieve better water run-off. You can elevate this or any rock in the wall by placing small, flat stones underneath the spillway rock. Bend the end of the tubing down towards the pond and place one or more capstones over it. This is where the waterfall’s “spout” will rest, so to speak. The “capstone” will partially hide the tubing and/or gently press it down against the second spillway rock. Make sure most of the capstone’s weight rests on the rocks between which the tubing is sandwiched or on small, flat rocks, so that the tubing isn’t flattened. You’ll have to play with the level of the spout, as you begin to fit in the second spillway rock.

Try to position your second spillway rock on top of your first spillway rock. Again, elevate the rock in the back, using small, flat rocks, to achieve a steeper pitch. One way to think of the placement of the two spillway rocks is that they’re like two shingles on a roof. They’re both on a slant, and the top one overlaps the bottom one, forming a continuous chute down which the water can pour. The position of the end of the tubing that forms the spout can now be determined more precisely, as you size it up on the surface of the second spillway rock. Again, pull the tubing to lengthen or shorten it, as necessary.

Fill the Backyard Waterfall

You’re ready to fill the pond with water, plug in the pump’s cord, and test the flow of your natural rock waterfall. No doubt, you’ll have to make several adjustments before you get everything right. The objective is to get the water to fall as close as possible to the middle of the pond, so that you can minimize water loss from splashing. There is some compromise involved with your cascade design: greater height equals greater visual impact, but greater height also equals greater water-loss, as the splashes will be more violent. Also, keep the height of your backyard waterfall in proportion with the size of your pond. A general rule of thumb would be, the smaller the pond, the shorter the rock waterfall.

After your backyard pond and waterfall are complete, check the water level periodically. The pump will burn out if the water level is too low. You should also turn off the pump overnight or when you’re leaving your property. This water feature is intended only for decoration and for relaxation (it’s not a fish pond), so there’s no reason to keep it running if you’re not there to enjoy it.

And we hope you do enjoy it for many years to come!