Super Team

Rain Water Harvesting

Is it possible to collect drinking water from a cadjan thatched roof?

Difficult. It is important to examine why the water collected from a cadjan thatched roof cannot be used as a source of drinking water.
The absorption capacity of cadjan thatched roof is at very high level and there is very little runoff water can be expected. Runoff coefficient of cadjan thatched roof is less than 0.5. Also, there is a greater possibility of contaminating and clogging the filter assembly of the tank by particles contain in the runoff water when cadjan thatched roofs are used. As a result of this much of the rain water will go waste.

However, still it is possible to collect rain water from cadjan thatched roof by covering the roof with a sheet of polythine. But this process is not fully fool proof as polythine sheet is very much liable to be get damaged and need to replace often. As such this cannot be treated as an efficient and low cost process for collection of rain water.



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