Hydrological data observation is specialized work and Central Water Commission (CWC) has been mandated to carry the same on national basis. CWC has developed enough expertise through its network of hydrological observation stations and has got trained manpower. At present, Central Water Commission is having a network of 878 sites on major rivers and its tributaries of India. In addition to this, Central water Commission is also having a network of 76 exclusive meteorological stations. The details of sites are as under: