ABSTRACT
Water scarcity and water security have already become global dilemmas to which numerous researchers commit to find sustainable solutions and Sri Lanka is growing in its vulnerability in terms of availability of healthy water resources suitable for human consumption. The study in this particular research is based on the already existent Rainwater Harvesting systems and statistical data obtained from those systems which are seemingly traditional and too conventional when compared to the global scenario. Modern problems require modern solutions and the endeavor here was to take the fundamentals of Rainwater Harvesting and build on them an optimized system in an innovative fashion with state-of-the-art characteristics. The project took place in Sri Lanka Ex-Servicemen’s’ Association building, Colombo.
The whole roofing arrangement of the building was linked into one main intake pipe via a gutter system which then guided itself to an intermediate rainwater storage tank after passing through a first flush diverter. The collection tank was then directed to the Combined Active Carbon and sand filtered Treatment plant with the aid of a 1HP pump. After filtration the water would then be directed to a storage tank from which the filtered water would be released to the building’s water supply through the same pump. In addition, an Electric powered Brackish Water Reverse Osmosis plant which is also a result of another resounding research, was introduced to the premises in order to improve the quality of the water consumed. And also, a coding was generated for an automatic plant watering system connectable to the Rainwater harvesting system and a prototype was constructed for trial purposes which yielded positive feedbacks.
The harvested water underwent testing for physical, chemical and microbiological qualities and the results were compared against nationally accepted quality standards from which the physical and chemical aspects proved well within safe limits for the water to be consumed. The microbiological results showed a presence of coliforms and E. Coli in the treated water to which addition of chlorine to the water storage tank was suggested as remedial action. Albeit the said complication the total output of the project was on a positive note which could be concluded in favor of the research objectives.
After careful studies and comparison with nationally and internationally accepted standards of water quality, it is well justifiable to conclude the implementation of the RHS as a success in terms consumption safety. Although, the cost-benefit factor should still be taken into concern and required actions to be taken earliest as possible. In addition, it is of prime importance that the construction RHS undergo necessary maintenance and supervision as the filtration and harvesting systems require an elevated level of attention.
