Informations et ressources scientifiques
sur le développement des zones arides et semi-arides

Accueil du site → Master → Ethiopie → Assessment of Surface Water Potential to Manage Frequent Drought Disaster (A Case of Dhas District in Borana Zone of Oromia Region, Ethiopia)

Addis Ababa University (2019)

Assessment of Surface Water Potential to Manage Frequent Drought Disaster (A Case of Dhas District in Borana Zone of Oromia Region, Ethiopia)

Alemayehu, Worku

Titre : Assessment of Surface Water Potential to Manage Frequent Drought Disaster (A Case of Dhas District in Borana Zone of Oromia Region, Ethiopia)

Auteur : Alemayehu, Worku

Université de soutenance : Addis Ababa University

Grade : Master of Science in Civil and Environmental Engineering 2019

Résumé
The study was conducted in Dhas district, which is located in Borana Zone of Oromia region ; geographically it is situated 4.00 o -4.39 o N and 38.39 o -39.46 o E with altitude range of 1082 – 1666m a.m.s.l. Total area of the district is 3,183.22km 2 ; its length from West to East is 120 Km and width from South to North is 41km. There is not any river and gauging station in the district ; the study was conducted aiming at estimation of surface water potential of the district and evaluation of its sufficiency for managing of drought disaster in the district. The surface water potential assessment of the district was conducted using SCS model with the aid of remote sensing and GIS. The assessment output was contextualized with the study finding of Genale Dawa integrated Master plan study (Dhas district is located in Dawa sub-basin ; finding from separate analysis of Dawa sub-basin was referred). For the recent land use/ land cover information of Dhas district ; satellite images were downloaded from USGS (United States Geological Survey) website with acquisition dates of December 2018, and the image processing was done using ERDAS Imagine 2015. With the aid of HEC-GeoHMS tool that is specifically designed in the ArcGIS environment to process geospatial data, the curve number was generated using the required information (hydrologic soil group, DEM, LULC map). The district was divided in to twelve sub-watersheds using Global mapped software, and direct runoff estimation was done for each sub-watershed separately ; the summation of direct runoff from each sub-watershed was made to get the total direct runoff amount of the district. Thirty years daily grid rainfall data that was collected from NMA was used for the estimation of the direct runoff. Estimation of runoff volume was computed for all thirty years period, and the estimated minimum and maximum runoff volume were found to be 8Mm 3 and 361Mm 3 respectively. Twenty years of forecast was made to estimate the major requirements in the district. Human and livestock’s water requirement estimation based on the population sized of 2039 was computed to be 10Mm 3 / year. The abundant of estimated runoff volume was evaluated, whether it is enough or not to satisfy the major water requirements in terms of managing the frequent drought disaster. As the analysis shows, Dhas district is having sufficient surface water potential that can be developed for managing of the frequent drought disaster in the district. This study was conducted focusing only on the available surface water potential of the district, and its sufficiency for managing of the drought disaster in the district. Its finding is also expected to be an entry point for development of the resource in the large scale. But for its implementation, it needs further feasibility and detail studies.

Présentation

Version intégrale (4,1 Mb)

Page publiée le 21 juin 2022