Working with Water
Working with Water at Taman Petanu
This page provides a few excerpts from the following document which explains the design plans for water management at the Taman Petanu Eco Neighborhood, including:
Rainwater harvesting
Water resource management
The neighborhood's water channeling paths
The Natural swimming pool
Black and Grey Water Treatment
For more complete information about the neighborhood's water and earthworks management plans please feel free to download this detailed document 'Taman Petanu Permaculture Water and Earthworks'.
Special thanks to Jeremiah Kidd, San Isidro Permaculture • Florence Catting of Wastewater Gardens International, and Dan and Aaron from Permaculture Solutions for their invaluable inputs on these plans.
Major sources of water at the Taman Petanu Site
Rainwater harvesting
This part of Bali is blessed with an ample amount of rainwater (2003-2007 annual average was 1,518 mm) that can be used in a variety of ways to suit the needs of the community.
Rainwater is suitable as the primary, if not sole, water source for all potable and irrigation needs. Rain has a mid to low pH and is a clean source of water equal to distillation or reverse osmosis filtering when falling from the sky.
Caught on a clean roof (such as metal or tile) and using a simple first flush diversion, the water is suitable for potable uses first; then again for irrigating food crops in the form of grey water as close to the source as possible.
Rainwater is the cleanest water that will enter the site and should be regarded as a great resource. It should be used for the highest water quality needs and kept separate from the other surface water coming from upslope property. Using the rainwater for the community needs will have the additional benefit of slowing and reducing the storm water saturation of the high clay content soil. It will also not exploit the ground water aquifer in keeping with the principles of the vision of Teman Petanu.
Water resource management
A water collection tank at each residence will serve several functions such as domestic uses, high quality aquaculture, irrigation, recreation (natural swimming pool), beauty, wildlife habitat and fire suppression.
These tanks will increase water security by not being dependent on municipal sources or unreliable electricity. Storage tanks can be made of polyethylene, steel, fiberglass, brick and mortar, poured concrete and ferro-cement.
In a tropical climate, ferro-cement is a great option due to the efficient use of materials needed for the size of the tank and the flexibility of the possible designs.
This Rainwater Harvesting Calculator was used to determine tank sizing for a rainwater catchment
The neighborhood's water channeling paths
Paths to resident’s houses from the main path end in a cul de sac that is retention ponds for excess storm water from overflow tanks from houses. This is good quality water that can grow aquaculture and also become a feature where people can gather. For further details about the the designs of the baths at Taman Petanu, see the Permaculture Plans page.
The Natural swimming pool
The aim of the neighborhood is to have a fully natural swimming pool.
Details of developing this wonderful technology in Bali’s climate and environment are currently being researched and developed by David Hutchinson. As as far as we are aware, even though many people are talking about the systems at this time, this technology has yet to be properly implemented on Bali and we are looking forward to actualizing a living model of this important eco-technology.
Black and Grey Water Treatment
Both Black and Grey water treatment is a priority at the neighborhood. Grey water treatment will be done through either a sand\gravel filter with an attached worm farm or reed beds. From there, subsurface discharge to fruiting trees, while where appropriate Wastewater Garden® black water treatment systems will be used. For further detail see the wastewater management section of the website.