This document summarizes a study assessing the surface water quality of Perumbakkam Lake in Kanchipuram district, South India using Geographic Information Systems (GIS). 15 water samples were collected from locations around the lake and analyzed for physicochemical parameters like pH, alkalinity, hardness, chlorides, TDS, fluoride, iron, and ammonia. The results were mapped spatially using GIS to analyze the spatial variation in water quality. Most parameters were within permissible limits except for high TDS levels at some locations, possibly due to industrial and domestic waste discharge. The study aims to help monitor water quality and identify sources of pollution impacting the lake.