Quality of hydro-meteorological data in remote stations: the case of Weito river watershed, Ethiopia

Abstract

Engineering studies of water resources development and management heavily depends on hydro-meteorological data. Some of the errors, manual or machine, might exist in the stream flow observation that we collect from different organizations. The main objective of this study was to identify the implications of hydro-meteorological data quality on water resources planning in Weito Watershed. Hydrological and meteorological data of 1985-2011 were collected from MoWIE and NMA. Grubbs T-test was used for identifying outliers in the observed data. In addition, F and t-test for stability of variance and mean were carried out, respectively. Estimation of D-days average minimum flow was also done. Based on 1985-2011 hydro-meteorological data, Grubbs T-value, F-test, and t-test yielded value of 2.86, 0.897 and -0.05, respectively. This indicates, stability of the historical data against mean and variance with no or insignificant outlying values. During the identified dry periods, average minimum flow during 7, 15, and 30 days showed water availability above 5m3/s in the river. The statistical data analysis test and D-days average minimum flow indicated no inflated historical data problem in Weito gauged near bridge. However, the local community did not agree with the results obtained. Therefore, we strictly recommend stake holders, research institutions, and organizations to further verify the quality of these data.