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.

Adding a Waterfall or Fountain

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 in, or outside the pond to keep water recirculating from the pond to the top of your outdoor waterfall, where it can plunge back down splashing into the pond.

With the pond complete, that means one of the two structures is out of the way. Now it's time to turn attention to the more exciting structure: the cascade design itself. And that means taking another look at the rocks that will be used.

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 as in the picture below.

Top Rock                             Middle Rock                 Bottom Rock

 

The size of your waterfall is another thing 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.

You'll have to choose a pump.

Waterfalls can be constructed atop level ground by using the dirt dug from the pond to create a berm 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.

TIP: 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 rock between the cascade stones.

Small support rocks between cascade stones -->

 

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, as they're simply stacked up over the edge of the pond.

In building you waterfall you should use top quality equipment and materials. The little extra money spent will save you future 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/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!

Plumbing - Some people like to create a raging waterfall while others prefer the trickle effect. The plumbing for either choice is quite simple and you should have no problems handling this yourself. Once you have selected a pump to create the desired effect for your waterfall, you will then need to select the appropriate size piping to match the pump. Pumps come with flow valves so that you can adjust the amount of flow to achieve just the right effect you desire.

Electricity - Pumps can be custom ordered with cords of various lengths which can be plugged into ground fault outlets from your home or other nearby structure/building. If your pond/waterfall is just too far away from an outlet you may need to hire an electrician to install a ground fault outlet nearer to your pond.

 

Tools and supplies needed to build your own waterfall:

Round and flat point shovel

Carpenters level

Can of orange spray paint

Plastic flower pot (large)

Rocks

Pump*

Tubing to run from pump to top of waterfall

Flexible** or rigid pond liner

Sand

* Remember not to skimp on the pump!

** Buy a crack resistant liner. (not rubber)

Use mostly flat rocks to construct the waterfall. We usually select one larger and thicker flat rock for the base of the waterfall. For the rest of the structure a mixture of sizes and shapes is fine, but include at least a few large, flat rocks. The rocks used in the waterfall, that will come into contact with spilling or trickling water, should always be angled slightly forward so that the moving water moves in the right direction: towards, and into your pond!

The idea behind the selection of spillway rocks for a cascade design is to choose rocks that are most likely to channel the falling water in the precise direction in which you want it to go. In addition to seeking out relatively flat rocks with sharp edges, see if you can find rocks that are slightly cupped. Occasionally you'll come across flat rocks that curl up ever so slightly at the edges, leaving a depression in the middle. The natural channel in such rocks will be greatly advantageous for the creation of the spillways in your cascade design.

After you've selected some rocks for your waterfall it's now time to start building. Actually, before you start building it there are a few other things you must do:

• Estimate the vertical height from the top of your pump to the top of your waterfall or stream and write this measurement down.
• Add another foot of height (or lift) for every 10 feet of hosing you will be using and write this measurement down.
• If you plan to have a stream a general rule of thumb is to figure your stream/waterfall requirement as 150 gallons per hour per inch width of the spillway or channel. For example, if your stream or waterfall spillway will be 10 inches wide, you will need a pump that produces a flow of 1500 gallons per hour (at whatever combined height of the feature and another foot of height for every ten feet of hosing to get there).
• This may sound a bit confusing so just write down all the measurements (heights and widths) you can think of so that when you consult with a professional he/she will have these measurement to assist you in determining the size pump you need.

NOTE: It is best to order a pump that will more than handle your needs as pumps come with valves that allow you to reduce the amount of flow.

Lay your bottom rock for the waterfall first. We usually select a large 2-3" thick flat stone of ample mass and place it so that it rests over the cavern we dug when excavating the pond. The front edge of this first flat rock should be postioned so that it will jut out over the water of the pond, forming an overhang that sits 3" or more above what will be the water level in the pond. If you need to raise this rock place smaller flat stones beneath it. When you have this first stone in place and set, run some water from a hose over it to make sure it is angled so that it spills into the pond.

TIP: The spillway rocks should be relatively flat (as opposed to rocks that are more rounded in shape). They should also have sharp, squarish edges. Water will cascade more cleanly over such edges. When rocks have blunt, gently-curving edges, some of the water tends to follow that curve and trickle back under the rocks. A little water trickling under is okay - the liner you placed beneath the waterfall will catch and drain it back into the pond.

Now you are ready to lay the next spillway rock. Select a few small stones close in size and lay them on top - along the sides and back of your base stone. Now, place the next spillway rock on top of these rocks. Once you have this rock in place perform the waterhose test and make any necessary adjustments. Below is another photo of that waterfall we built.

TIP: Typically, when building rock waterfalls, it's a good idea to stagger the levels.

Small Stone to hold tubing in place----> Top Rock-->         Spillway Rock Staggered Back---> Small stones used to elevate ------------------->   Bottom Spillway Rock--------->

Do the same thing for the top spillway rock as you did for the second spillway rock. If you look closely you'll see that we used a small boulder with a concave in the center as out top spillway rock. After using small stones to elevate your top spillway rock do the waterhose test again to make sure all spillway levels are spilling properly. make minor adjustment if necessary using small slivers of flat stone to increas elevations here and there.

NOTE: You may want to continue laying levels, until you've reached the height you desire. Our pond was three levels.

You're almost done now. It's time to install and hook up the pump.

Place your pump in the cavern under the waterfall, or somewhere close to the waterfall if you didn't dig for a cavern. Attach the tubing to the pump as shown in the manual that came with the pump. Your tubing should be laying alongside the waterfall, though you have probably already figured out how to disguise it and cover it up with a few rocks.

Now go to the back of the waterfall berm and place the top end of the tubing on top of the top spillway rock. Use a small 'cap' rock on top of the tubing to hold it in place as shown in the photo above. You'll might have to play with the cap stone a little to acheive good water flow.

Now, 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 into the pond with as little trickling beneath and behind your spillway rocks as possible.

NOTE: There's some compromise involved with your waterfall design: greater height equals greater visual impact, but greater height may equal greater water-loss. Another consideration on height: keep your natural rock waterfall in proportion with the pond. A general rule of thumb would be, the smaller the pond, the shorter the rock waterfall.

It took two of us a day to build the pond and the waterfall y've seen in the photos above. After reading all of these instructions it may seem like a difficult thing to do: to build your own pond. It's not. However, if you feel intimidated don't hesistate to contact and consult with a local pond building expert.

Happy water gardening!