Salt pans act as the alternate habitat for migratory and resident migratory
shorebirds, East Coast of Tamil Nadu, India

Abstract :

Puducherry is one of India’s Union Territories and is located along the Eastern coast of India. Since it is administered by the Central Government, taxes are lower and amenities better than in the surrounding areas of the State of Tamil Nadu and with a high level of tourism, Puducherry is subjected to urban sprawl. Most of Puducherry’s urban areas depend on groundwater. Available rivers and lakes are considered to be polluted for domestic use. This study endeavors to assess the inter-monsoonal dynamics of the quality of groundwater. Water samples were collected in 55 locations in and around Puducherry during pre-monsoon (March 2014) and post-monsoon (December 2014). The water quality was assessed by determining 23 types of physical, chemical and biological parameters (pH, electronic conductivity, turbidity, alkalinity, total hardness, total dissolved solids, calcium, magnesium, sulphate, phosphate, potassium, sodium, fluoride, chloride, iron, zinc, lead, manganese, copper, chromium, cadmium, total coliforms and E.coli) by standard operating procedure (SOP) according to the BIS standard. The results from the water quality parameters were mapped using ArcGIS software in which spatial analyst was used to produce basic interpolated maps. Inverse Distance Weighting (IDW) method was used to obtain the spatial distribution of the water quality. The Water quality index was calculated for individual sample point comparing both pre and post- monsoon data, through the Canadian Council of Minister of the Environment Water Quality Index (CCMEWQI) method, and the results were then represented as maps using the IDW of ArcGIS spatial analyst tools. The results obtained showed that there is high variation between the different seasons in water quality parameters. The water quality is considerably better in post-monsoon compared to pre-monsoon. The EC, fluoride and iron show high fluctuations between the two periods. The South-West and North-East part of the city have poorer water quality, with other areas along the borders and towards the coast showing fair water quality, but a large area of the urban has good water quality. This study also will serve as a useful baseline for future water quality analysis in Puducherry,and we argue for the necessity to monitor water quality given the urban sprawl, increasing industrialization, and shrinking space available for agriculture.