How To Build a Garden Pond With A Waterfall

Though many of your own smaller creative decisions will be made during the process of building your garden pond, below are some general guidelines you can follow for construction of a small garden pond.

NOTE: The instructions provided below assumes you will be using a flexible type liner, such as 45 mil rubber liner.Step-By-Step Instructions

Begin by using marking paint, or lay out a garden hose, to outline the shape of your pond. This outline should be the perimeter shape of the water surface area.

Most pond excavations have flat ledges - called "plant shelves" - at different depths all around the perimeter. These plant shelves allow for the placement of different types of plants that require different depth levels to grow properly. Paint out these lines for shelves as well. You'll want a deeper area (24-36") for fish to hide and stay warmer during winter. Then a shelf level at 12-24" deep for certain plants, and another shelf level at 6-12" for certain other plants. If you look at the picture below, you'll notice I left an area to the far left that is very shallow. When the pond is filled with water, this area might be two or three inches deep. This is for animals and birds to use as drinking and bathing source.

Caution: If you have even the slightest suspicion that you will be digging near buried cables make sure to call your local utility companies to have the location of these cables marked before digging.

Now that you've outlined your pond excavation may begin. Start by first digging out the deepest section of your pond. If you plan to have fish, make sure to dig one section of the pond at least 24-30" deep by 18" wide to provide a safety zone if predators come around. Dig this hole in a central location within the perimeter of your pond. Post hole diggers or a trenching shovel may be necessary for digging narrower holes.

If the ground area around your garden pond is flat, you can use the excavated dirt to build a mound(s) that will serve as the foundation where your waterfall(s) will be located, as seen in the picture above. Build the mound for your waterfall anywhere from 12 to 36" in height. Likewise, additional excavated dirt can be used to create a low raised berm around the entire pond. This helps prevent backflow from entering your pond water when there is heavy rainfall.

Note: Before installing your liner. You will need to flatten the tops of the berms so that stones will lay flatly upon them.

If you are building your pond into an embankment, pile the excavated dirt around the lower side of your pond forming a berm that will be equal in height with the base of your waterfall(s). This will ensure that when you fill your pond with water, liner won't show on the side where your waterfall is located.

After digging out the deepest area of the pond (24-36" depth), work outward digging the next level to 18" depth, and then the next to 12" depth.

Tip: If you plan to use a submersible pump, and would like to make sure that it is hidden from view, excavate an area that will be underneath the base rock of your waterfall. This area should only be wide and deep enough to house your pump and the container or pot that you will enclose it in.

After excavation is completed, remove any rocks, sticks, and other debris that might poke a hole in or cut your liner. Smooth all surfaces with your hand. If you want to be on the safe side, line the floor and interior walls of the pond with an inch or two of sand, a 1/4 -inch layer of newspaper or carpet, or a couple layers of landscape fabric.

Liner size is calculated based on the width, length and depth of the excavation, the size and number of plant shelves, and the amount of edge overhang, so the sizing will be more accurate if done after the excavation is complete.

To measure for your liner, use a sewing or construction measuring tape. Start by measuring the length at the widest point. Place one end of the measuring tape at a point 12-18" outside the perimeter of the excavated hole, or beyond the base of a berm if you built one. Press the measuring tape against the ground, going over berms and down through the excavated hole and back up over the other side to a point 12-18" beyond the perimeter of the excavation or base of a berm. Make sure measuring tape is always contacting the soil over any shelves and levels. Write this measurement down. Do the same for the width. 

Note: To ensure your pond liner will be large enough, you may want to add an extra foot or so to both the length and width. You can always cut to reduce the size of a liner but you can't make it larger!

So that you'll know how many gallons of water your pond will have when filled, take several measurements of the various depths of your pond. Note the width and length of the areas at the various depths as well. Write these measurements down on your design if you did one. Also measure the height of your waterfall. These measurements will allow a pond store professional to determine what size of pump will be necessary for your waterfall.

Note: If you will be constructing a tall waterfall, over 24' in height, additional measurements will need to be taken in order to purchase an addition liner to cover the foundation of your waterfall. Measure height of waterfall so that your waterfall liner will extend from a point beneath the waterfall, to a point where your liner will drape over the back and down to ground level.

You want to wait until the excavation is completed and the measurements mentioned above have been taken before purchasing the pond liner, pump, filter, and other supplies.

Before installing the liner, make sure you have flattened the top of any perimeter soil berms. If you did not fill excavation with sand and/or carpet, make sure that any stones or other sharp objects have been removed. Rub your hands over the surface of the soil to make sure everything is smooth.

With a couple of people helping, the liner is unfolded into the excavation. It's best to do this with bare feet, or soft-soled shoes. The liner is then smoothed into place from the center-bottom up, and is lapped over the top edge of the pond 6 to 12 inches. A small amount of water is typically added to the bottom of the pond to weigh the liner down and help with the smoothing process. Folds in the liner, which will be necessary to help it conform to the curves of the pond sides, are incorporated as the liner is smoothed out.

Place the submersible pump in the bottom of your pond (or in the cavern you built under the base rock of the waterfall). Attach tubing and drape over the waterfall foundation.

A filter is optional, however, if you want to keep your pond water clear and free from algae, a filter that contains a UV light is highly recommended.

There are filters that you can place within your pond, or those that can be installed outside the pond. I like using the one's that go outside the pond. The filter will have an intake and an outflow. You will run a hose or tube from your pump to the inflow on the filter. Then you will run a hose or tube from the outflow that will go to the top of your waterfall.

Once the liner is in place, and your pump and filter have been installed, if desired, you may begin to add rocks or small boulders to the INTERIOR of the pond. Rocks that will be placed beneath the water surface should be washed and scrubbed thoroughly to remove all dirt and other particles.

Now you can begin to add water! It could take some time to fill your pond with water using a garden hose. 

Note: Scroll down for detailed instructions for constructing a waterfall

While the pond is filling, use the time to begin placing exterior rocks around the perimeter of you pond, including the ones that will serve as your waterfall. Start by placing flat stones around the perimeter of your pond and the rocks that will serve as the base of your waterfall(s). Allow these flat stones to hang a little over the edge of where the water will be when the pond is full.

Then place rocks or boulders of random size and shape atop the flat stones. 

Make sure the liner, pump and tubing for the waterfall are all in place. See detailed instruction for building the waterfall below.

Add plants in and around your pond, mulch around the exterior plants, and continue to fill your pond with water. When the pond is full of water all that's left to do is turn on the pump!

Outdoor waterfalls come in all shapes and sizes and make for emphatic focal points. When mulling over your design options, the main consideration is how to achieve the necessary height and overall size for the waterfall. Too, you will need to select the type of stone or other material that will be used to construct the waterfall. Select materials that will fit in and compliment the surroundings.

Waterfalls can be simple or elaborate, designed to empty into a single pool or pond of water, originating from a flowing stream and falling through several tiers, or cascading dramatically from many feet above the ground. In planning to build outdoor waterfalls, you need to concentrate on two structures:

Once these two structures are in place, you'll use a pump, inside or outside the pond, to keep water recirculating from the pond to the top of your waterfall, where it can plunge back down splashing into the pond.

The size of your waterfall is something to be considered. Design your pond to match the size of your outdoor space; not too big, not too small. Accordingly, design your waterfall to match the size of the pond it will spill in to.

In building you waterfall, you should use top quality materials. The little extra money spent will save you replacement costs and maintenance headaches in the future. The amount you will need to spend for construction will depend on the overall size of the pond and waterfall. Whatever you do, do not skimp on the pump that will generate the moving water over your waterfall and into the pond. To build a reliable and beautiful waterfall you will need the right rocks (in the right places) and lots of moving water.

Waterfalls can be constructed atop level ground by using the dirt dug from the pond to create a berm aside/behind the pond. If you are lucky enough, your waterfall can be built into an existing slope on your property. Either way it will require some work. You will need to lay a flexible liner beneath the stones used to construct the waterfall. This liner should drape over the backside of the berm or go above the top rock on a slope and at the bottom should drape over the liner used in the pond so no water can escape.

Most likely, you'll be building the waterfall with rocks. One alternative to using natural rocks placed atop a liner for a waterfall is to use pre-cast concrete forms that mimic stone for the cascading structure. They're compact and easy to install, but you'll have to decide if these look natural enough for your taste. They are not natural enough for mine. 

If you go the natural route, the most important rocks are what might be termed the "spillway" rocks. "Spillway" means the rocks directly over which the water will cascade. In a cascade design you will use two or more rocks, one above the other, and so on, as shown in the picture below.

Note: Before laying the liner you should stair-step the face of your berm for the waterfall. This will allow you to place the back edge of your flat cascade stones flatly. The front edge of the cascade stones can be held up and adjusted for water flow by placing small rocks or flat bricks between the cascade stones.

As shown in the picture below, you can use bricks or flat stones as spacers between the spillway stones in your waterfall. If these are visible after completion, you can hide them by placing smaller, natural stones in front of them.

Don't let any of this technical information about pumps scare you away! A few simple measurements you take can provide your pond supply source or local pond consultant with the information needed to assist you in choosing the right pump. Just remember this: DO NOT skimp on the pump!