Changing needs for appropriate excreta disposal and small wastewater treatment methodologies or The future technology of small wastewater treatment systems.

Recent developments will strongly influence the design and utilization of small wastewater treatment systems in the future, e.g. population increases in non-sewered rural areas and developing countries; increasing impairment of surface water quality; the construction of occupied high-rise buildings in metropolitan areas; the development of planned but somewhat isolated communities, growing shortages of water that mandate reuse of wastewaters. It is well known that there is a very strong linkage between wastewater disposal methods in rural areas and developing countries and the general health of the population. These problems could be greatly reduced or prevented by the utilization of well known excreta disposal and small wastewater treatment system technologies, but the development of more innovative on-site systems is needed. It is expected that future environmental and public health pressures in developed countries will require increasingly stringent effluent limitations for small and on-site wastewater disposal systems, based primarily on nutrient discharges. Both on-site and small-scale technologies are available for the more stringent requirements, but innovative and more economical designs are needed for wide-spread acceptance. Water reuse should be a consideration for the designs of these systems. Implementation and utilization of well known technologies are needed, but the obstacles are often more social and political than economical.