Dr Ole Ersson developed a self-built rainwater harvesting and purification system in Portland, Oregon, in 1996, using low-cost components to create potable water.
His system includes catchment, first-flush diversion, filtration, UV purification, storage, pressurization, and backflow prevention to ensure safety and code compliance. Source: http://www.rwh.in/ .
A 1500 gallon plastic cistern.Back flow prevention system.Rainwater Purification System.
The major components of a rainwater harvesting system
The major components of a rainwater harvesting system
Collection system: Roof surface and gutters to capture the rainwater and send it to the storage system
Inlet filter: Screen filter to catch large debris
First flush diverter: Diverter that removes debris not captured by the inlet filter from the initial stream of rainwater
Storage tank: Storage tanks composed of food-grade polyester resin material approved by the U.S. Food and Drug Administration (FDA), which is green in color and helps to reduce bacterial growth
Overflow: Drainage spout that allows for overflow if the storage tank gets full
Controls: Control system that monitors water level and filtration system
Treatment system: Filtration and disinfection system that treats the water to non-potable or potable standards
Pump: Pump to move water through the system to where it will be used
Backflow prevention: Backflow preventer to ensure that under negative pressure water cannot flow backwards through the system into the make-up water system
Flow meter: Flow meter (with data logger) to measure water production
Power supply: Systems may use either conventional power sources or, to improve off-grid capabilities, alternative sources such as stand-alone or grid-tied solar systems
Water level indicator: Monitors the water level in the storage tank.
Different Components of Rainwater Harvesting System
Basic Components: Regardless of the complexity of the system, the domestic rainwater harvesting system comprises six basic components:
#1 Catchment surface: the collection surface from which rainfall runs off #2 Gutters and downspouts: channel water from the roof to the tank #3 Leaf screens, first-flush diverters, and roof washers: components which remove debris and dust from the captured rainwater before it goes to the tank #4 One or more storage tanks, also called cisterns #5 Delivery system: gravity-fed or pumped to the end use #6 Treatment/purification: for potable systems, filters and other methods to make the water safe to drink.
Homepage: http://www.rwh.in/ Rainwater harvesting is the capture, diversion, and storage of rainwater for a number of different purposes including landscape irrigation, drinking and domestic use, aquifer recharge, and stormwater abatement.
In a residential or small-scale application, rainwater harvesting can be as simple as channeling rain running off an unguttered roof to a planted landscape area via contoured landscape. To prevent erosion on sloped surfaces, a bermed concave holding area down slope can store water for direct use by turf grass or plants. More complex systems include gutters, pipes, storage tanks or cisterns, filtering, pump(s), and water treatment for potable use.
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