Idukki has many unique topographical and geographical characteristics. Idukki is the largest District of Kerala with an area of 5105.22 sq.km. About 97 percent of the total area of the District is covered by rugged mountains and forests. There is only a strip of Middle land (3%) in the western part of the district. Low land area is totally absent in the district. More than 50% of the area of the district is covered by forest.
Altitude (Above Mean Sea Level) Land Pattern Percentage of Land Area 20m - 100m Midland 4.5 100m - 300m Mid - upland 7.5 300m - 600m Upland 12.1 600m - 1200m Western Ghat High Range 48.3 1200m - Above Top Western Ghat High Range 24.5
There are 14 peaks in the district which exceed a height of 2000 meters above M.S.L. They are Anamala, Eravimala, Tathumala, Chenthavara, Kumarickal, Karimkulam, Devimala, Perumal, Ghudoor, Kabhula, Devicolam, Anchanad, Sabarimala and Karimala. Anamudi (Anamala) the highest peak south of Himalayas is in the Kuttampuzha Panchayat of Adimali Block and in the K.D.H Village of Devikulam taluk. The estimated height of the peak is 2817 meters.
As the district lies mostly in the highland, it is covered with dense forest, steep hills, and deep valleys. Because of the undulating topography large area of the district is not suitable for scientific cultivation.
Land Holding Pattern
Area No.of Holders The Percentage Upto 1 Ha. 1,69,822 80.42 % Between 1 and 2 Ha. 30,283 14.34 % Above 2 Ha. 11,069 5.24 %
The important rivers of the district are Periyar, Thodupuzhayar and Thalayar. Periyar which is 277km. long is the second longest river of Kerala. It originates from Sivagiri in the southeast part of the district and touches all the taluks of the district. The Periyar is harnessed at various points in its course for generating electricity and for irrigation purpose. Mullaperiyar dam, Idukki Hydro-electric project, Idamalayar Hydro electric project and the proposed lower periyar are constructed across the Periyar.
Kundala Dam, Mattupetty Dam, Munnar head works, ponmudi dam and the kallarkutty Dam are constructed across the various tributaries of Periyar. There are a few natural lakes in the district. They are Eravikulam and Devikulam lakes in Devikulam taluk, Elavizhapunchira, in Thodupuzha taluk. Two types of the soil are found in the district. The highland area is covered by forest soil(Alluvial soil) and the other parts by laterite soil.