Regional relationships between basin size and runoff characteristics

Abstract

The effect of basin size on runoff characteristics is investigated. The maximum observed floodflow, the maximum annual constant loss, the lag time and the unitgraph peak for a certain storm duration of basins in the western and northwestern regions of Greece are increasing power functions of the basin size. These functions explain significantly the variation in the runoff characteristics. For both regions single relationships are derived for the latter two characteristics, whereas for the two former ones they vary regionally in accordance to the climatic conditions. Thus, care is needed in transferring such relationships outside the location of their derivation; besides, the transferability of the values of their parameters is doubtful. The derivation of the relationships in the specific area of interest is thus suggested. The regional relationships are used in predicting accurately design floodflows, annual runoff yields and unitgraphs of various storm durations for ungauged basins in the regions studied, needed for the hydrological design of water resources development systems. © 1984 Taylor & Francis Group, LLC.