|ॲक्सेसदिनांक=2007-09-12}}</ref> Sandyवालुकामय areasभाग areनदिकिनारी foundआणि along the river banks and coastsसमुद्रकिनारी, suchजसे as [[Thiruvanmiyur]]थिरुवणमियुर, [[Adyar (Tamil Nadu)|Adyar]]अद्यार, [[Kottivakkam]]कोट्टिवक्कम, [[Santhome]]संथोम, [[Georgeजॉर्ज Townटाऊन, Chennai|George Town]], [[Tondiarpet]] and the restतोंडीर्पेत ofइत्यादी coastalठिकाणी Chennaiआढळतात. Here rainwater [[Surface runoff|runoff]] [[percolation|percolates]] quickly through the soil. Clay underlies most of the city including [[T. Nagar]], [[West Mambalam]], [[Anna Nagar]], [[Villivakkam]], [[Perambur]] and [[Virugambakkam]]. Areas of hard [[rock (geology)|rock]] include [[Guindy]], [[Perungudi]],[[Velachery]], [[Adambakkam]] and a part of [[Saidapet]].<ref name=rain_water_harvesting_TN_gov>{{स्रोत बातमी
