Feasibility of Rainwater Collection Systems in California.

摘要

The northern California drought of 1975-77 emphasized the need to explore alternatives for water supply. This research examined the feasibility of collecting rainwater for domestic consumption from roof areas into storage tanks. Rainfall records for 13 representative California locations were analyzed to provide a basis for estimating the supply of water from rainwater collection systems. Standard statistical measures of central tendency, distribution and variation, as well as serial correlation, were remarkably consistent. The concentration of lead in rainwater near urban areas frequently exceeds the recommended limit for drinking water, which would imply that rainwater supply systems are feasible only in rural areas. Microbiological contamination of rainwater results from bird droppings on the collection area, but chlorine disinfection proved effective. Turbidity can be removed to below the limit recommended for drinking water by a process of alum coagulation and settlement, feasible on a household scale.