4th International Conference on Rain Water Cistern Systems
Manila , Philipines - August, 1989

Section E: Environmental And Water Quality Aspects

Paper E.3

Investigation Into The Quality Of Roof-Harvested Rainwater For Domestic Use In Developing Countries: A Ph.D Research Study

Dr. George Michaelides
Dundee University, UK

Abstract

Features in design, maintenance and operation of roof rainwater harvesting systems which affect the quality of the water obtained have been investigated by a research study of Dundee University in 1982-1985 A complete rainwater harvesting system for domestic water supply was built in the tropical environment of Mauritius incorporating features, excluding water treatment, that would optimise water quality. A programme of water quality monitoring was carried out mainly involving 55 bacteriological samples and 3° chemical samples from the water abstraction point at weekly intervals. The faecal coliform test was negative in 84% of the samples and the mean faecal coliform count was 1-1 per 100 ml. The results of total and faecal coliform examination would be acceptable by WHO Guidelines in 80% of the samples and fully or almost fully acceptable by other guidelines. According to these results, no water treatment is required. Even though pH and conductivity were high initially due to the leaching of cement from tank walls, the aesthetic water quality is also acceptable.

The diversion of the initial flush of rainwater, which is foul, was examined in the laboratory and new foul flush diversion systems were developed at Dundee University.

PDF of full document available to members (11pp, 220kb)