ABSTRACT
The quality of treated municipal wastewater depends to a great extent on the quality of the munici pal water supply, nature of the wastes added during use, and the degree of treatment the wastewater has received. Generally, if the supply water used by the municipality is of acceptable quality for irrigation, the treated municipal wastewater will also be of acceptable quality, although somewhat degraded. There are few instances in California where treated municipal wastewater quality is so poor as to prevent its use for crop and landscape irrigation. The main exceptions would be in areas where salty groundwater seeps into wastewater co11 ection systems or industrial wastes with an unacceptable contaminant are discharged into municipal wastewater collection systems. Because wastewaters contain impurities, careful consideration must be given to water quality in order to evaluate the possible long-term effects on soils and plants from salts, nutrients, and trace elements that occur naturally or are added during use or treatment. These effects are normally manageable if problems associated with these impurities are understood and allowances are made for them.
