الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Municipal wastewater is the combination of liquid or water carried wastes originating in the sanitary conveniences of dwellings, commercial or industrial facilities and institutions, in addition to any groundwater, surface water and storm water that may be present.
Untreated wastewater generally contains high levels of organic material, numerous pathogenic microorganisms, as well as nutrients and toxic compounds. It thus entails environmental and health hazards and, consequently, must immediately be conveyed away from its generation sources and treated appropriately before fInal disposal. The ultimate goal of waste water management is the protection of the environment in a manner commensurate with public health and socio-economic concerns.
Methods of wastewater treatment were fIrst developed in response to the concern for public health and the adverse condition caused by the discharge of wastewater to the environment. Also important, as cities became larger, was the limited availability of land required for wastewater treatment and disposal, principally by irrigation and intermittent fIltration are methods commonly used in the early 1900s. The purpose of developing other methods of treatment was to accelerate the forces of nature under controlled condition in treatment facilities of comparatively smaller size.
In general from about 1900 to the early 1970s treatment objectives were concerned with (1) removal of suspended and floatable material, (2) treatment of biodegradable organic, and (3) elimination of pathogenic organisms.
from the early 1970s to about 1980, wastewater treatment objectives were based primarily on aesthetic and environmental concern. The earlier objectives of BOD, Suspended solids and pathogenic organisms’ reduction continued but at higher levels. Removal of nutrients such as nitrogen and phosphorus also began to be addressed, particularly in some of inland streams and lakes. A major effort was undertaken to achieve more effective and widespread treatment of wastewater to
. improve the quality of the surface waters. These efforts resulted in part from (1) an increased understanding of the environmental effects caused by wastewater discharges, (2) a developing knowledge of the adverse long term effects caused by the discharge of some of the specifIc constituents found in wastewater.