ABSTRACT
Providing water and sanitation needed for increasing numbers of people with limited financial investment is an enormous challenge (a challenge taken up first in the International Drinking Water Supply and Sanitation Decade (1981-1990), then by Safe Water 2000 and Health for All 2000, and most recently by the WEHAB initiative as part of the World Summit on Sustainable Development held in Johannesburg in 2002). The greatest need can often be found in the peri-urban areas where slums and shantytowns (so-called informal or transitional settlements) proliferate in many Third World cities. These are rarely given services prior to their establishment and subsequent provision places severe financial strain on already over-stretched government resources. Yet, if these basic services can be provided, the hope is that better public health will allow an upward spiral of social and economic development, leading to increased productivity, higher standards of living and improved quality of life (Okun and Ponghis, 1975).
