Usefulness of a regional probabilistic approach to determining design discharges of hydropower plants in Albania

Abstract

This paper presents the results obtained using the PARDES-flood method in Albania to determine discharges of hydropower plants. The first part of the method is a regional probabilistic approach to extreme rainfall. The second part is related to the determination of extreme maximum peak discharges thanks to two probabilistic relations between statistical quantiles. The original approach in the first part lies in combining the probabilistic theory of Poisson’s process, regional analysis and the integration of particular phenomena linked to orographic features. The rivers studied in Albania include the Vjosa, which flows through the southern part of the country. It has a total length of 272 km, 80 km of which are in Greece. In this geographical area we have 13 rainfall stations at our disposal (not counting the numerous stations available nearby) and seven discharge measurement stations with data covering the period 1951-1992. The regional analysis of rainfall across this catchment area revealed a homogeneous precipitation regime. The rainfall-runoff probabilistic correlation analyses confirmed the relations from the PARDES model and revealed saturation at a return period of 4 years.