In this study, in order to estimate flow for basins which have insufficient or unavailable flow data, the data of 39 streamflow gauging stations (SGS) in the Eastern Black Sea have been used. 10 yearly discharge values and location data for each SGS, as well as, temperature, precipitation and location data for meteorological stations have been obtained and drainage areas have been determined. Annual temperature and precipitation values for each SGS were calculated by Thiessen Method. The fitness of the discharge data to some statistical distributions were tested by both chi-square and probability plot correlation tests and variance analysis was applied for each station. Depending on the discharge data, weighted moments, L moments and L moment ratios were calculated for each station. The best fit distribution was determined as the Lognormal Distribution by L moment ratios and the parameters of lognormal distribution have been correlated by topographic and climatic parameters of each SGS. Discharge values and some topographic data were selected as independent and dependent variables, respectively. Drainage area and stream density, total stream length and mean slope of tributary values were topographic; and mean annual precipitation height and temperature values were climatic parameters. Both linear and nonlinear simple and multi regressions were studied for the analysis. It has been determined that the correlation coefficients are high and the relative errors are at acceptable levels and it has been concluded that these equations are reliable.
Key Words: Discharge, Eastern Black Sea, L-Moments, Regression Analysis