Orthophosphates in the Shallow Groundwaters of South India

Detectable amounts of phosphates occur in the groundwaters of many parts of South India. Excessive concentrations occur in isolated parts either due to pollution of village wells or other cultural practices. The results of analyses carried out in 1982 and 1983 show significant differences indicating a general variability in the source. The excessive phosphate content in Chirala (10mg/l) and Bapatla (7mg/l) need further investigation. In most of the other areas, local geology and prevalence of phosphate bearing minerals play an important role in giving the observed phosphate content. Developing towns with no proper sewerage also show higher phosphate content in groundwater (e.g.; Karimnagar in Andhra Pradesh gives phosphate up to 1.5 mg/l).