The first step to consider is to decide what type of pond you want to build. You should first consider what type of aquatic life you want in your pond. Is it going to be a home for goldfish or koi? Or is your main concern for the collection of aquatic plants? Perhaps you only want the pond for the sound of a waterfall. Each type of pond will need to be planned for its specific features. Keep in mind that the most common mistake water gardeners say they made when building their first pond was making it too small. A small pond limits the number of fish and plants you can add. The two “basic” ponds are the “koi pond” and the “water garden.”
The “koi pond” is different from a “water garden” because koi limit the amount of plant life available to be grown. Simply put: koi eat some varieties of plants. A koi pond should also be larger because koi get quite large despite the size of the pond. It is recommended that a koi pond be no less than 1000 gallons in volume; the bigger the better. It also needs to have an area in the pond at least 3 feet deep, 4 – 5 feet deep is even better.
The “water garden” type pond typically contains both goldfish and a variety of aquatic plants. Water gardens are far more popular in our area. They do very well in moderate climates. I usually recommend that they are designed to be at least 2 feet deep.
The next step is to select the proper location for your pond. Most ponds will be enjoyed more if they are installed close to the home. Select an area where you can see the pond year round. Ponds are great attracters of wildlife, including birds and butterflies. Remember to position the pond where runoff from rain will not flow into it. Runoff can carry fertilizers, chemicals, and organic debris which can be damaging. You will also want to take trees into consideration. Excessive falling leaves and other debris will only cause you headaches.
Ideally, you’ll want at least 4 to 6 hours of direct sun if you want to grow water lilies. Shade is fine for fish-only ponds, however, plants require sunlight. Water circulation is not essential but the use of a pump will allow you to keep more fish, it will also keep your plants healthier, too. Keep in mind that a pump is required to run a filter, fountain, or waterfall. The sound of running water adds greatly to the enjoyment of the pond. Most ponds will benefit from the use of a biological filter, also. This is essential if you are keeping koi or more than a few goldfish.
The next major step is to determine the size of your pond. The best way to do this is to use a rope or water hose and lay out the shape on the ground. Remember, a pond for goldfish or water lilies need be only about 2 feet deep in one area. Ponds built for koi should be close to three feet or deeper to allow these larger fish enough space. The biggest mistake that most people make in building a pond or water garden is making it to small. A larger pond is more stable and easier to maintain. Keep in mind that your finished pond will typically be about 30% smaller than you visualize it. After you have laid out the shape, measure the maximum length and width. Add the depth twice to these measurements plus a foot or two for overlap and this will give you the pond liner size.
Once you know the location and size of your pond, next comes excavation to the right size and depth. You’ll want to begin by digging a shelf around the perimeter of the pond about one foot deep and one or more feet wide. Dig the remainder of the pond with a slight slope to the end opposite the waterfall if one is included in the design.
Once you have your hole dug, you’ll want to position any external pond filters and/or pond skimmers in their proper location. Pond skimmers should be buried to the proper level beside the pond. A ditch should be dug for the plumbing from the pond to the waterfall or external pond filter. If a pond skimmer is being used, dig a ditch to the external pond pump and from the pump to the external pond filter or waterfall. If you are using a submersible pump in the pond skimmer then the ditch will be from the skimmer to the external pond filter or waterfall.
Next, you will want to install a pond liner. You can purchase the liner pre-cut or by the foot at your local Nursery & Landscape Supply. Your liner can be cut with scissors or a utility knife. You may want to tape any small pieces together to keep them from moving when the pond liner is placed. Position the liner evenly in the pond. Try to minimize folds and wrinkles but some will be necessary. After the water is added, the folds should flatten out.
Now you are ready to excavate for any streams or waterfalls. An external pond filter or waterfall tank can be positioned to create the first waterfall. This can be placed to spill directly into the pond in which case the pond liner is held against the pond filter until you are able to stack stone from the pond shelf up against the pond filter to create a waterfall. If a small pool or stream is desired then excavate this several inches deep and to the desired size and shape.
Position the underlayment and pond liner allowing extra material to overlap several inches into the pond. Plumbing from the pump can be brought over into the stream or pool or again if using an external pond filter this will be the start of the waterfall. Streams should be dug wider than the finished size to make room for stone that will be placed into the stream for the edging. Stone can be secured to the liner with mortar or expandable foam. This will hold back the water allowing it to spill over the stone creating the waterfall. Next, you’ll want to connect the pond liner to the skimmer, if one is being used, following the manufacturers directions. Place the pipe or tubing in place leaving a few inches extra to make your connections later.
Now that your pond is in place, you’re ready to place stone or other coping around the edge of the pond. Arrange the copingstone around the edge of the pond and fold the pond liner up behind the stone to slightly above the water level. It is usually not necessary to mortar the stone into place if it is of sufficient size to be stable. If using small stone, or if people will be walking around the edge, then mortaring the stone for stability may be required. Back fill with soil to hold the pond liner against the stone.
Now you’re ready for the fun part, the filling of the pond with water. Fill the pond with water to within a few inches from the top and then make corrections if necessary to ensure that the pond is level. As the pond is filling, remove wrinkles and make folds as necessary. You’ll want to add a dechlorinator to the water to remove any chlorine or chloramines.
The last step will be the addition of plants and / or fish. My advice is always to add aquatic plants as soon as possible after constructing the pond or water garden. Next you may add packaged bacteria to seed the pond filter and pond. Fish should be added a few at a time over several weeks to allow the bacteria to establish in your water garden. Any water lilies or other plants with surface leaves should provide shade to approximately 2/3 of the surface area if in full sun. If less than full sun then less coverage is advisable.
There is no doubt that some of the most impressive homes along the Central Coast are identified by water features. Ponds offer great diversity to your landscape and welcome the curiosity and appreciation of your family and house guests. Should you consider the installation of a pond or water feature, feel free to contact me at email@example.com or at (831) 455-1876.