The present study was conducted to assess the contamination of Chatta Canal due to the discharge of huge quantity of effluent from tiny and small scale (SSI) textile bleaching, dyeing and printing units located at Kalikapur under Maheshtala region (22.29°N, 88.11°E). Apart from effluent the canal also receives household wastewater from neighborhood. The study revealed that the chemical parameters of canal wastewater like chemical oxygen demand (979±459.92 mg/L), biochemical oxygen demand (365 ±174.78 mg/L), suspended solids (110±41.47 mg/L), total dissolve solids (3394±580.94 mg/L), carbonate (867±203.00 mg/L), Chromium (0.061±0.03 mg/L) and Lead 0.103±0.04 mg/L), E. coli (380000±213044.59 CFU/100 mL) measured as per APHA (1998) exceeded the maximum permissible limits laid down by WHO (2003). The approach adopted in the present study ascertained the seasonal variation of physico-chemical parameters particularly in summer, rainy and winter seasons and water quality index during those seasons. The study indicated that quality of canal water is very poor for domestic, industrial and agriculture uses. Hence it reflects the usefulness of the analysis of surface water quality assessment. It appears that contaminated surface water requires total treatment to put aside degraded agricultural land, crops, fruits and vegetable required for human consumption.

Keywords: Canal; Bleaching and Dyeing Effluents; Seasonal Variation; Water Quality Index;