Principles of swimming ponds
These have been featured in magazines recently baecause of the Kings Cross swimming pond development.
Swimming ponds in a garden setting:
- Use plants to keep the water clear
- Have at least 50% of your total water area as a planted zone
- Create bacterial conditions in the planting area among the plant roots to help cleanse the water.
- Encourage micro organisms like water fleas to thrive.
- Do not use chemicals or chlorine
- Brings the swimmer closer to nature
- Encourages many species of wildlife creature to colonise this new garden habitat.
- Exclude fish and ducks from your swimming pond. Both create high levels of nutrient and bring a risk of unhealthy impurities
- Allow 'swimming ponds' to fit into the garden rather than looking like a separate, functional item in the garden
- Can be a safety hazard for children. Monitor children near deep water as this is hazardous for the young who are instinctively drawn to water.
- enables supervised children to see nature close up.
Constructing a swimming pond:
- Usually built by specialist swimming pond contractors.
- Create a deep area for swimming (at least 2.4m = 8ft deep) with one liner
- Create a separate area for the plants of a shallower depth that has its own liner - called regeneration zone.
- Separate the 2 areas by a barrier that allows the water to flow across the top of the barrier between the 2 areas. This barrier should not allow materials like soil to spill from the planting zone into the swimming zone.
- Install a circulatory pump system to keep the water moving.
- Include a biological filter unit.
Planting swimming ponds:
Densely plant with a range of aquatic plants - submerged oxygenators, waterlilies, floating plants, shallow marginals, deep marginals, bog and waterside species.
- Use indigenous Native plants that grow vigorously and also include Non-Native ornamental varieties.
- Non-Natives will increase the range of colour and flower type and extend the season of interest and the period of active nutrient usage in the regeneration zone.
- Aim for at least 9 plants per m2 of planting area.
The shelf plants favoured for a swimming pond are:
- British Native - tall and structural - Cyperus longus, Iris pseudacorus (Yellow Flag Iris), Butomus umbellatus, Alisma plantago-aquatica, Lythrum salicaria, Caltha palustris, Carex acutiformis
- Non Native plants - other Iris - versicolor and louisiana Black Gamecock, Pontederia cordata, Anemopsis californica, Typha lugdunensis
- Rafting plants that grow out across the water surface - Myosotis scorpioides (blue or white), Veronica beccabunga, Mentha aquatica, Oenanthe javanica Flamingo
- Deep water plants give surface cover and put shade across the pond surface. Pond Waterlilies (any colour) and Aponogeton distachyos.
- Submerged plant growth: Oxygenators - Ceratophyllum demersum, Myriophyllum spicatum, Potamogeton crispus
British Native structural plants we suggest:
Non-Native structural plants: