Master gardener Paul James discusses the how to of constructing a water feature in your landscape.
Although the new water feature in master gardener Paul James' landscape isn't finished, the overall construction is done. The project began a few months ago with the help of several crew members and the expertise of a landscape designer who specializes in water features.
The first step to creating the water feature was laying out a garden hose to determine the overall shape of the stream and pond. Once that was decided, the crew started digging along the edges of the entire length to define the perimeter. With that task complete, they began removing all the sod.
The location of the waterfall was determined. A roughly 12-inch-deep hole was dug to accommodate the black box, which creates the waterfall and also contains a filtration system. The crew made sure the box was level after placing it into the hole. With that done, a three-inch flexible pipe was glued to the waterfall box, then snaked through a trench toward the pump box.
The crew excavated the pond, reserving some of the soil to create a berm or raised area around the edges of the pond. In addition, some of the removed soil was also used to bury the waterfall box. With much of the excavation complete, it was easy to see the upper and lower portions of the water feature.
A hole was dug at the lower edge of the pond for the pump box, which also included a leaf skimmer basket and a small filter.
Any roots along the edges of the pond had to be trimmed away to prevent them from puncturing the liner. The pump box was placed in position and checked for level.
While the crew continued digging, the edges of the stream were fine-tuned by adjusting a hose along the desired perimeter. Tiers were dug into the stream bed so that the water would flow easily downhill. At select locations along the stream and pond, holes were also dug to create spots for bog plants. The crew laid the landscape fabric and cut it to fit. This serves as an additional protection for the liner, which was placed on top and trimmed to eliminate any creases.
Next, it was time to add several pallets of limestone. Working from the bottom up, the stones were placed in a slight outward angle for stability, with care not to damage the liner along the way. Then a few limestone boulders were cleaned up with some water and added. Landscape fabric and a section of liner were added to the stream. Big flat stones were placed around the edges of the pond, and small flat stones were used as shims to stabilize the larger stones. Mini boulders were placed around the edges to vary the height. Next, river rock was added to the bog holes and more mini boulders along the edge. River rock serves to cover the liner. The stones along the stream were placed more deliberately since most of those will be viewed from above.
Fairly large boulders disguise the back of the waterfall box, while smaller stones were stacked along the front. A 1600-pound boulder in midstream splits the flow of water into two channels; seven people pitched in to move the huge rock. To protect the liner, the boulder was rolled down two wooden planks.
"It was a brutal job," says James, "but worth every ounce of effort."
He finished plumbing the pump to prepare the water to move up from the pond to the waterfall and stream. A layer of river rock was added to the stream bed.
Finally, it was time for the magic moment: the pump was turned on and the water flowed.
"It all came together beautifully," says James. The water flowed from the waterfall, down the tiers of the stream, cascaded over the final fall rock and into the pond.
"I've skimmed over certain details of construction — in particular, the plumbing details involved with both the pump and waterfall box. But honestly, the instructions that come with those kits are quite clear. Even someone with little or no knowledge of plumbing — myself included — can handle the installation."
Given the enormous popularity of water features in landscapes these days, James will return to this spot now and then to discuss things such as pond maintenance, aquatic plants, and fish — in particular, koi.