While seismologists in general have time and again debated the suspicious role of the Koyna reservoir in the occurrrence of frequent earthquakes in western Maharashtra, results of detailed research work being conducted by the Central Water and Power Research Station, Pune since 1963, clearly establish a strong correlation between the unusually high seismic activity in the region with the impoundment of the Koyna reservoir.A scientific paper authored by the former joint director of the Station Dr S.K.Guha on the basis of research conducted by the CWPRA and published in 1992 clearly speaks of earthquakes observed in the Koyna region as distinctive of reservoir induced seismicity(RIS). The paper in fact describes Koyna resrvoir as a "classic" case of RIS.