Valapatnam

The Valapatanam River rises South of Ammatti village in the district of Coorg in Karnataka State at 750 52’ East longitude and 120 13' North latitude at an elevation of 900m above MSL. The river has a total length of 101 km from its source to its outfall into the Arabian Sea. The river drains an area of 1,867 sq km. of which 546 sq km lies in Karnataka and the rest in Kerala. There is one CWC Hydrological Observation Station at Perumannu on this river.

The climate of this basin is characterised by heavy rainfall, high humidity and oppressive weather in hot season. The maximum rainfall observed is 4268 mm and minimum 2369 mm. The temperature varies from 22.00°c to 32.90°c .The velocity of wind varies from 8 km/hr. to 12.6 km/hr.