Decide on the pond’s basic shape and size as well as its location.
Design your pond and stream with different views in mind. Take advantage of a natural slope for a stream and several small waterfalls. Create a pond that is an accent to the yard, not one that overpowers it. Place the pond close to your home so it can always be enjoyed.
Use local stone to make the waterfall seem more natural.
Clear away sod and/or brush. Measure and mark out the maximum dimensions of the pond with spray paint (Image 1). To create the pond shape, lay a garden hose to fit the dimensions and then adjust it to create flowing curves and a natural shape (Image 2). Using spray paint, trace out the final shape of the pond (Image 3).
Lay out the top Biofalls filter and the bottom skimmer filter. Laying out the filters determines the water flow of the pond and will act as a guideline for pond and stream design. Lay the top filter at the highest point of the stream and pond (Image 1). The bottom filter has a catch basket and should be placed as far away as possible from the water source on top (Image 2). There should be no dead zones in the pond. A dead zone is an area in the pond where there is little or no water circulation. Connect the two filters with a flexible PVC pipe near the perimeter of the pond (Image 3). Excavate using a shovel or a pick axe. The PVC pipe is durable, so the trench does not need to be deep.
Dig the entire pond one shovel depth (approximately six to eight inches). As you dig out, use the excavated earth to fill in low areas or build up height in other places of the water feature. Compact the newly placed earth using a hand tamper so it won’t shift. After the first level has been built, dig out a second inner level another six to eight inches. Follow with a third level. The maximum depth of the pond should be approximately 18-20 inches.
Place the bottom filter in the excavated pond. Dig out the space for the top filter, place the filter and level it. To ensure that the top filter does not move, build a natural looking berm around it with the excavated earth and stones to provide stability.
Install the underlayment over the filter; you’ll cut it down to size later. Start at the bottom of the pond and fit the underlayment to the pond shape by pleating the material. Install the liner in the same manner. The liner should be fish safe and carry a long warranty.
Place the stones. Placing stone in the pond serves many purposes: stone keeps the liner in place, protects it from ultraviolet rays and makes the pond appear natural. Stone also creates a surface for algae and microorganisms to colonize on.
To determine the total tonnage of boulders, larger stones, needed for your pond, take the length times the width of the pond and divide it by 65. A quarter of that tonnage should be small stones, a quarter should be large stones and half should be medium-sized stones. To figure out the amount of smooth gravel used for filler and for covering the liner, take the boulder tonnage number and multiply it by .45.
Start arranging stone in the pond. Pay attention to the ratio and incorporate a variety of sizes in the pond. Place the larger stones first and then fill in with gravel. To create a natural looking stream, begin with jagged ledge stone and use smaller stones on the inside and bottom of the pond so that the stone appears to have been smoothed by tumbling down the pond. Create fish caves in the pond to protect the fish from predators.