However, due to the sheer size of the pond, additional filtration was needed beyond skimmers and waterfalls to ensure its appearance remained natural. Therefore, a bog filter was installed to help maintain the water. This area was dedicated for the dense planting of water-loving marginal or bog plants. It is a smaller, supplementary pond that is typically 10 to 20 per cent of the size of the main water feature. A bog filter can be located inside or adjacent to the main pond. For this project, it was installed within the main pond.
Water was pulled from one of the skimmers at the opposite end of the pond and pumped into the bottom of the bog area. The slow flowing water then rises up through the roots of the plants where natural biological filtration takes place before the water flows back into the pond. The bog not only provides this required filtration, but also ensures incredible beauty when all of the plants are in bloom.
To ensure the proper movement of water within the pond, underwater jets were also added. These jets pull water from one skimmer and push it into the bottom of the pond, forcing water to circulate in the deepest point of the pond to avoid water stagnation from occurring.
Next step, waterfall building
This design called for a main waterfall to be built 3.6 m (12 ft) wide by approximately 2.4 m (8 ft) high. The waterfall needed to be dramatic in appearance and sound, bearing in mind this was a residential project.
Further, the scale had to be such that it was in keeping with the pond’s size, but not too big that it detracted from the feature’s natural appearance. The first step involved using clean soil to create the rough shape and drop points of the waterfall. Geotextile was placed on the soil followed by the waterfall liner. Starting from the pond elevation and working up, the waterfall was built in levels. The bottom drop, where the water cascades into the pond, needed to be constructed at the right level; therefore, knowing exactly where the water level was going to rest in the pond was a must.
More than 80 tons of boulders were slung into position one by one and, like the pond, once the first waterfall level was built, the liner was folded up to allow clean soil to be placed underneath. Then, the liner was folded back in place before building the next level.
Constructing the waterfall of varying drop heights and cascades gave it a natural appearance, but more importantly it achieved the soothing sounds of moving water the client was expecting. On the opposite side of the main waterfall, a secondary waterfall was built. The purpose of this waterfall was not only to provide additional filtration for the pond, but also to enhance the view of the feature from other areas of the property. This waterfall was smaller in size, but incorporated a 3-m (10-ft) long stream. More than 113,562 L (30,000 gal) of water pours over the waterfalls every hour.
A pond at night is an awesome sight
Pond and waterfall lighting is a must for a water feature of this scale. As such, light-emitting diode (LED) lights were added at varying depths within the pond, which transforms its appearance during the evening hours. The waterfall and stream lighting creates a dramatic look as the water ripples past the lights. Finally, underwater lights also accent the strategic placement of a stump and log placed within the bog. (The stump and log were removed during the excavation and it seemed appropriate to reuse them in the finished feature).
Within the pond is an array of aquatic plants. Water lilies flourish within the deeper portions of the pond, while shallow water plants grow with the edge rocks. Their colour and beauty not only help to soften the appearance of the large-scale feature, but also provide an additional area for wildlife to flourish. Carefully selected terrestrial plants were placed around the perimeter of the pond and waterfall to complete the natural setting and to co-ordinate the water feature with the existing landscape.
Bring on the water
The pond holds more than 302,833 L (80,000 gal) of water and several water trucks were required to fill it. All in all, the six-week project was completed on time and on budget, and exceeded the homeowner’s full expectations.
Phil Jackson is president of Jackson Pond and has worked in the water feature industry for 25 years. From their design centre and retail store in Burlington, Ont., Jackson Pond builds and maintains award-winning water features across North America. He can be reached via e-mail at phil@jacksonpond.com.
