Physicochemical characteristics of Vasishta Godavari estuary, east coast of India: Pre-pollution status

Abstract

A comprehensive survey of the pre-pollution status of Vasishta Godavari estuary was undertaken between October 1981 and June 1983 in order to assess the impact of pollution to which the estuary would be subject with the exploitation of oil in its basin. Base line data for various physicochemical parameters were obtained during October 1981-June 1983. Influence of seawater was felt in the estuary up to distance of 40 km from the confluence forwards the upper reaches. Salinity stratification was more marked than that of temperature. The lower reaches were more turbid than the middle and the upper. Often the water column was supersaturated with oxygen. Concentration of inorganic phosphate was much less than in other Indian estuaries and nitrite was added on to the system in moderate quantities by the farm-drainage flowing into it. Silicate was in sufficient quantities all through the non-flood period.