Abstract:
Estimation of inflow design flood i.e. Probable maximum flood (PMF) for major storage reservoirs is most
important parameter. The consequences of a failure of the structure due to improper estimation of PMF
could be calamitous in terms of loss of human lives and damage to property. PMF which is estimated from
probable maximum precipitation (PMP) is used as inflow design flood for major projects. PMP is the
greatest depth of precipitation for a given duration which is physically possible for an area. Various methods
such as statistical, empirical, storm maximisation and transposition approach, and dynamic approach are
used for estimation of PMP. This paper presents unit hydrograph method which reflects all physical
characteristics of the catchment for obtaining PMF hydrograph. The study area selected is Nira-Deoghar
dam which is located on River Nira in the Krishna basin, Maharashtra, India. The outcome of PMF in Indian
scenario is very much important since it is directly related to dam safety.
