DISTRICT

DISTRICT PROFILE is one of the coastal district lies in the South eastern corner of Tamilnadu. It is bounded on the North by & district by in the East, District in the West & South West. It lies between 8019’00” N Latitude and 78040’00” E Longitude and has an areal extent of 4621 sq.km. Thoothukkudi district is divided into 8 taluks. The taluks are further divided into 12 blocks, which further divided into 462 villages.

PHYSIOGRAPHY AND DRAINAGE Thoothukudi district is one of the coastal district of Tamilnadu. The drainage network in the district is constituted by the rivers originating in Western Ghats and Tamilnadu uplands and flowing towards the Bay of Bengal. Few streams originate in the hillocks within the district and confluences directly with the sea. Vaippar and Karamaniyar are the major rivers draining the area which are ephemeral in nature. Tamirapani is the major and perennial river in the district with a mature stage of development and on the way receives several important tributaries such as Karaiyar, Servalar, Manimuthar, Kadana, etc.,

RAINFALL The district receives the rain under the under the influence of both southwest and northeast . The northeast chiefly contributes to the rainfall in the district. Most of the precipitation occurs in the form of cyclonic storms caused due to the depressions in Bay of Bengal. Precipitation is the lowest in August, with an average of 3 mm. Most precipitation falls in November, with an average of 238 mm. The southwest monsoon rainfall is highly erratic and summer rains are negligible. .It is the minimum around Arasadi (577.4 mm) and Thoothukkudi (582.8 mm) in the central eastern part of the district. It gradually increases towards south, west and north and attains a maximum around Kayattar (722.5 mm) and (734.8 mm) in the northwestern part.

CLIMATE The annual mean minimum and maximum temperatures are 23.780 and 33.950 C respectively. At an average temperature of 31.6 °C, May is the hottest month of the year. In January, the average temperature is 26.5 °C. It is the lowest average temperature of the whole year. GEOLOGY Rock type found in the area belong to the Khondalite and Charnockite groups and Migmatite Complex of Easter Ghats Super group (Archaean Age), which are unconformably overlain by Tertiary and Quaternary sediments. Garnet-biotie-sillimanite gneiss, quartzite, calc-granulite and limestone of Khondalite group with epidiorite occurring as narrow linear bands. Charnockite group is represented by acid variants. These rock types occur as xenoliths within the Migmatite Complex occupies a major part of the area, comprising medium grained hornblende-biotite gneiss and garnet-biotite gneiss. Gypsum, limestone, beach sand, kankar and shell limestone are the economic minerals of the district. Hard Rocks - 73% Sedimentary Rocks - 27% HYDROGEOLOGY The district is underlain by both porous and fissured formations. . The important aquifer systems in the district are constituted by i) unconsolidated & semiconsolidated formations and ii) weathered and fractured crystalline rocks. The occurrence and movement of ground water in these rocks are under unconfined conditions in the joints & fissures and dependent on the nature and extent of pores and interconnection of fractures zones. The morpho- tectonic analysis of the crystalline tract indicates the presence of deep seated tensile and shear fractures particularly along the fold axes. These tension joints and fractures and shear fractures at deeper depth of 30 to 100 m have been acting as conduits for ground water movement. The depth to water level in the district varied between 1.20 – 12.12 m bgl during premonsoon (May) and varied between 0.33 – 9.24 m bgl during post monsoon (Jan). The seasonal fluctuation shows a rise in water level, which ranges from 0.20 to 8.41 m bgl. The piezometric head varied between 2.40 to 11.00 bgl during pre monsoon and 0.33 to 9.24 m bgl during post monsoon .

SUSTAINABILITY With a view to enhance the Sustainability of the drinking water sources, recharge structures are being implemented by TWAD Board under various State and Central Government assistances. The Recharge structures implemented so far is as under

GROUND WATER POTENTIAL (as per CGWB) The ground water resources have been computed jointly by Central Ground Water Board and State Ground & Surface Water Resources and Development Centre (PWD, WRO, Government of ) RURAL HABITATIONS Total no. of rural habitations : 1740

FLORA Vallanadu Blockbuck Sanctuary lies in the hilly areas of Thoothukudi district. Kurumalai and Vallanadu hills are the important hills in this area. The most common trees that are found here are pine trees, , Betel Palm, Jamun and Mangoes. Beautiful fern and varieties of orchids grow on the trunks of the trees. Dalbergia multiflora, Dichrostachys cinerea, Acacia latronum, Acacia planifrons, Albizia amara, Zizyphus Species and a few Azadirachta indica, Dodonia viscose, Carissa carandus, Pterolobium indicum and Euphorbia Acalyphia fruticosa, Ocimum sanctum species form the undergrowth. FAUNA In Vallanadu Blockbuck Sanctuary, diverse and colourful wildlife exists and it includes Blackbuck, Spotted deer, Macaques, Jungle cat, Mongoose, wild hares, Black naped hare, Scaly Ant eater – Pangolin, Viper, Rat snake, Peacock, Heron, Stork, Grey Partridges, Jungle Craws, Common quails, Pied crested Cuckoo, Crested hawk eagle, Black winged kite, Curlew, Lapwing, Sparrows, Horned owl and other nearly 100 species of birds are found in this area. A major attraction just 22 km northwest of Thoothukudi is Mayura Thottam. It is a peacock farm situated at .