Department of Environmental Sciences, Tamil Nadu Agricultural University, Coimbatore-641003, Tamil Nadu, India
*Corresponding author: E Mail: nandaens@gmail.com
Online published on 7 April, 2014.
An assessment on the impact of discharge of coffee processing waste water on Kodavanar river water was made by analyzing the physico-chemical parameters of the river water from its point of origin down to the point where it is mixing with Kamarajsagar Dam at periodical intervals. The duration of study was from February 2005 to March 2007. From the impact assessment study it was observed that the polluting parameters like total solids content, biochemical oxygen demand (BOD), chemical oxygen demand (COD) and hardness of the Kodavanar river water were higher than the prescribed limit during the coffee proessing season (September to January) compared to that of off season i.e. February to August. The maximum BOD values for the river water was recorded in the coffee processing season i.e., 16 per cent and 32 per cent increase over fly picking and off-season respectively. The values of COD of river water ranged from a minimum of 24 mg L−1 to 98 mg L−1 in off-season and to a maximum of 48 mg L−1 to 128 mg L−1 in coffee processing season in all the sampling points. An increase of 23 per cent of COD concentration was observed in coffee processing season compared to off-season. The maximum values of TS ranging from 240 mg L−1 to 1400 mg L−1 were recorded in the coffee processing season. This was 25 per cent and 54 per cent increase over fly - picking season and off-season respectively. The chloride concentration was ranged from a minimum of 20.5 mg L−1 to 56.9 mg L−1 in off-season to a maximum of 14 mg L−1 to 92.3 mg L−1 in coffee processing season. Similarly other parameters such as, sodium and potassium were also high in coffee processing season compared with the off- season.
Impact assessment, coffee processing wastewater, Kodavanar river, water qualities
