A design and feasibility study of rainwater-collecting system for Kuching population

• Main Author: Kiu, Kwong Lieng
• Format: Thesis
• Language: English
• Published: Universiti Malaysia Sarawak (UNIMAS) 2001
• Subjects: TD Environmental technology. Sanitary engineering
• Online Access: http://ir.unimas.my/id/eprint/27993/1/KIU%20KWONG.pdf; http://ir.unimas.my/id/eprint/27993/

This research looks into the design and feasibility study of rainwatercollecting system that would complement the plumbing designed by engineers and accepted for so many years. The rainwater-collecting system could harvest and utilize the rainwater that otherwise would become overland flow, and finally discharged to the municipal storm sewer system. With a rainwater-collecting system, 'free' rainwater would be stored in a rain water storage or retention tank and then used for flushing toilets, or other uses, which does not necessitate the use of clean chemically treated water. In this study, different rainwatercollecting system components were studied and designed, namely retention tank, diverter, filter, and backup system. The rainwatercollecting system mounting methodology was studied to ensure the system is technically feasible. The rainwater-collecting system feasibility study was carried out in the later part. The feasibility study is based on availability of local technical support, economic benefit study, and social acceptability study. In the research, the average domestic water demands for different uses that do not necessitate the chemically treated water was estimated. The rainwater harvesting capacity was estimated based on the local precipitation data. The rainwater-collecting system installation cost was also estimated by interviewing the local experienced technicians. The collected data from the above mentioned studies were used for the feasibility study in the later part. The purposes of the feasibility study are to ensure the rainwater-collecting system is technically, and economically viable, and also socially acceptable to targeted population. The results have shown that, there are sufficient technical supports from the local workshop for fabricating the rainwatercollecting system. The mounting method of the rainwater-collecting system is also properly designed according to BS 5950. The social acceptability result shows that, majority of the house dwellers have positive acceptance toward the rainwater-collecting system. It is also found that the rainwater-collecting system is economically viable to the house dwellers. The estimated economic return is 7.2% per year, which is 4-5 times higher than current average interest rate.