DIY: How to Build a Better Pond
What to know before you break ground.
By Cathy Babcock

Water holds a great attraction for most Arizonans. A properly constructed water garden can provide a beautiful focal point and a soothing place to relax. As with any DIY project, planning is key.
BEFORE YOU START
Contact Arizona 811 (arizona811.com), a damage-prevention service that will mark all underground utilities. Also, check with your homeowners association and the city in which you reside for any required permits or fences. You’ll also need an area to stage your materials and put the excess soil from digging.
LOCATION
If you want plants in your pond, six hours of sun in the morning is best for those that bloom. For Arizona, afternoon shade is practically mandatory. Avoid areas with mature plants that may have big root systems and seasonal leaf drop. Don’t build in low-lying areas of the yard, and avoid your roof’s drip line. All parts of the pond should be easily reachable without having to get into the water. Situate near a grounded exterior outlet for the equipment.
SIZE AND DEPTH
Sylvia DeVisme, owner of The Lily Pond, believes in going as big as possible. “What starts out looking like the Grand Canyon turns into the incredible shrinking hole as you add the liner, equipment, plants and fish,” she says. When digging in hard clay soil, alternately wet the area and then loosen with a digging bar. For caliche, rent a jackhammer. A 4-foot by 6-foot pond will support one water lily, a few grasses and three to four goldfish. Vertical sides will help keep cats and raccoons out.
POND DESIGN
Be creative. A below-ground pond can be designed in any shape and then lined with an EPDM (ethylene propylene diene monomer) liner, which must be cut to size. Be sure the liner you buy is fish-safe if that will be a factor.
EQUIPMENT
Ponds require a pump to circulate water, and a filter and aerator to control algae. The size of each will be determined by the size of your pond. Equipment should be able to cycle all the water at least every hour. Many gardeners use a float to automatically fill the pond, but some water must be removed on a regular basis to avoid salt and mineral accumulation. Purchase liners and other equipment only from a pond supplier.
PLANTS
Plants should cover at least 60 percent of the water surface in the summer to keep water cool and subdue algae. Hardy perennial water lilies (Nymphaea spp.) do best in Arizona and go dormant in the winter. Water lettuce (Pistia stratiotes) is a good surface floater. Bog plants, such as Yerba Mansa (Anemopsis californica) and Umbrella Plant (Cyperus alternifolius), can be added in and around the edge of your water feature.
FISH
Fish need a pond depth of at least 2 to 3 feet to have room to swim. Koi should not be kept in a pond that is less than 3 feet deep. That little thumb-sized baby will become the equivalent of a Great Dane in a small pond. Goldfish are an alternative. Do not add aquarium fish. Once your pond is established, fish don’t need to be fed, but most people provide them with food to entice them to the surface.
MAINTENANCE
No pond is maintenance-free. Filters must be changed or cleaned. Algae and debris must be removed. Plants may die and need replacing. Equipment requires upkeep to function properly.
Another key for Arizona ponds is water movement, which can be created by such features as a waterfall. Not only visually attractive, they also provide aeration and give fish the oxygen they need.
While a pond can be a commitment of time and maintenance, it can also be a source of enjoyment year-round. For more info, consult The Greater Phoenix Pond Society (phoenixponds.com).