How to Build a Pond

Water's beauty and the calming sounds it creates always provide a peaceful, natural atmosphere for any garden or backyard. If you don't have a natural water source on your property, you might consider building a pond. When done right, a pond can be not only a stunning feature but also highly beneficial: it can become an ideal habitat for various wildlife. Read the guide below to create either a natural pond or a decorative fish pond to enhance your backyard.

Decide on the type of pond you want. What is the purpose of your pond? Think about the features that you would most like to incorporate as you begin to plan. Here are some of the most popular types of backyard ponds:

• A natural pond is perhaps the easiest to create as it requires no pump or electricity. This type of pond is designed to blend seamlessly into the overall landscape. Since fish are not introduced, this pond will attract frogs, snails, water spiders, and other animals who will come to bathe or drink from it.
• A decorative fish pond is primarily an aesthetic feature. This type of pond often includes water lilies and other aquatic plants, designed to complement the garden's overall design. Common features of this pond include artistically arranged rocks, a small waterfall, and a few goldfish.

Select the location for your pond. The best spot for your pond is one that enjoys both sun and shade, allowing plants to thrive and maintaining a safe level of algae in the water. You might also want to place the pond in a location visible from inside your home, so you can admire it even when it's raining or cold.

• If you're building the pond in your backyard, the first step is to contact your utility providers for electricity and water, and ask them to mark any underground lines. This ensures you avoid these areas when digging your pond.
• If you own a large plot of land, you may need to take additional steps. Contact your local agricultural authorities to check if your property lies within a river basin or protected watershed, and whether there are any regulations for pond construction.
• Avoid placing the pond too close to trees, as digging may damage their roots.

Determine the size and depth of your pond. If you live in a humid climate, such as in Southeast Vietnam, your pond should be about 1-1.5 meters deep and wide. However, in a dry climate like Central Vietnam, a small and shallow pond will lead to quick evaporation of water. Do some research to decide on the appropriate depth for your pond.

• Larger ponds are easier to maintain because they offer greater stability, allowing plants and animals to thrive.
• Use a rope to mark the desired shape and size of the pond, and keep it in place while digging.

Digging the pond. For smaller ponds, using a shovel is the easiest option. Here are some important points to keep in mind while digging:

• If you want to support the development of plants and animals, make sure your pond is deep enough to prevent freezing in the winter. In colder climates, the pond should be about 1-1.5 meters deep to ensure wildlife can survive the winter.
• Your pond should have a sloping area, like a beach, to allow animals to crawl out. Steep, vertical sides can trap them and cause drowning.
• As you dig, pile up the excavated earth for use as the pond's edge.
• Once you've finished digging, remove any sharp-edged rocks from the pond's bottom.

Line the bottom of the pond. The first layer should be sand. Make sure to cover any cracks in the pond’s base with sand. Next, line the pond with a layer of artificial or biodegradable material. You can use newspaper or burlap, but biodegradable materials are preferred because they decompose over time and leave only the sand layer behind. Stones can puncture the sand liner, so consider using biodegradable materials like synthetic mats or specialized pond liners. Afterward, cover the liner with a wide waterproofing layer.

• You can find various waterproofing liners at construction material stores or garden supply shops.

Fill the pond with water. Use a pump to fill the pond until it's full. Be sure to stop before the water overflows the edges.

• You can use rainwater to fill the pond if you prefer not to use tap water.
• Trim off any excess waterproof liner, leaving about 12 cm around the edge.

Create a small trench around the pond. Lift the liner and use a spade to dig a trench about 16 cm wide around the pond. Press the spade down to a depth of about 10 cm, then tilt it to be parallel with the ground and gently lift the grass to form a trench. Lay the waterproof liner back over the trench, then place the grass back on top. This method will make the pond’s edges look more 'natural,' attracting a variety of wildlife.

Get water from a nearby natural pond. Use a large bottle or another container to collect water from a clean natural pond near your house. Be sure to take water from an established pond, not from a neighbor’s. Fill your container, taking care not to scoop up any fish. Then, bring it back and pour it into your pond. Natural pond water contains beneficial bacteria and microorganisms that help create a natural habitat for wildlife.

Monitor the 'natural' development of the pond. Over time, your pond will evolve, fostering nutrients, attracting insects, and other creatures.

• Do not remove the grass around the pond; instead, allow it to grow naturally.
• For the first few years, avoid introducing fish into the pond. The presence of fish may deter frogs, snails, and other wildlife.
• Create mud in the pond by adding a layer of topsoil. You can plant cattails or other aquatic plants like water lilies to support the growth of other species.

Dig the pond. A decorative pond typically features multiple layers, making room for a waterfall and a place for the pump. If you plan to use electrical equipment, ensure the pond is near your house for access to power. Use a shovel to dig the pond to your desired size and depth.

• If you plan on using a pump, you should dig an additional 25 cm deep hole at the center of the pond.
• Create a secondary tier for aquatic plants by digging a shallower layer along the pond’s perimeter.
• You can use a pre-formed pond liner, which can be found at garden supply stores. These liners typically have a bean shape and multiple levels. If you decide to go with a liner, adjust the hole you dig accordingly.

Line the pond. The first layer should be sand to cover all cracks. Then, add a layer of biodegradable material like newspaper or burlap. Finally, place a waterproof liner on top, covering both the base and the edges of the pond.

Install the pump and other equipment. If using a pump, position it in the deepest central tier and make sure the pump’s hose extends over the pond’s edge. You can also install a filter or skimmer. Contact the equipment manufacturer for detailed installation instructions.

• Do not place the pump directly on the ground, as it may become obstructed by dirt or debris. Instead, raise it on a bucket or plant pot that is at least 8.62 cm high.

Create the pond’s edge. Trim the liner so that only about 12 cm extends above the edge of the pond. Dig a small trench below the liner, fold the liner over, and place heavy, flat stones on top. River stones are a great choice for this.

• Make sure the stones are placed in the trench, around 10 cm deep, so that their height is level with the water when the pond is full.
• If the stones are large and heavy, mortar isn’t necessary. However, for smaller stones, it’s recommended to use mortar to keep them in place and prevent shifting when someone steps on them.
• If you’re adding a waterfall feature, be sure to surround it with stones for added effect.
• Be creative: experiment with different shapes, sizes, and colors of stones to make the garden more visually appealing.

Fill the pond with water. Use a hose to fill the pond until the water level reaches the edge, but not to the point of overflowing. Test the pump and other installed equipment to ensure they are working properly.

Set up an aquatic garden. Plant water lilies, reeds, and other aquatic plants in your pond. Each plant has specific requirements, so ensure that the environment you create is suitable for the plants you intend to grow. For instance, some plants don’t thrive in moving water, so avoid placing them near the waterfall.

Add goldfish. Head to a local aquarium store and buy a few goldfish to place in your pond. Research which aquatic plants are best suited for goldfish. Avoid adding too many, as they can harm the aquatic plants.

• If you maintain a balanced ecosystem between plants and fish, you may not need a filter. However, if you have too many fish, you may need to install a filter to handle the waste they produce.
• Koi carp are different from goldfish and require a specialized pond setup. Refer to articles on Koi pond construction for detailed instructions.

• Water hyacinths, when well-maintained, absorb nutrients from algae, helping to keep the pond water clean.
• Nearby garden centers are great places to find aquatic plants, stones, statues, and fountain kits for your pond.
• Wait until the pond's temperature and pH levels stabilize before adding fish, which may take a few days.
• Remember, a fish pond is not suitable for wild flora and fauna, as fish may eat frogs, toads, and salamander eggs. Carefully consider the wildlife species you want to host in your pond.
• Local pet stores are ideal for buying fish. However, it's a good idea to call ahead to ensure they have the type of fish you're looking for. Large fish pond species often sell out quickly, and some smaller stores may not carry them.

• When selecting aquatic plants, ensure that the species are safe for your fish and other household pets, as some plants can be toxic.
• Familiarize yourself with local regulations regarding pond safety. Certain areas may require a fence around ponds that reach a specific depth.