Groundwater Resources Management in Lake Awassa Catchment, Southern Ethiopia

Abstract

The study was conducted in Lake Awassa catchment 275 km south of Addis Ababa to assess the problems that arise as a result of improper development and utilization of groundwater resources and to recommend management options by giving particular emphasis to investigate current status of groundwater structures and management practices. The hydrology of the basin was characterized by land use, soil, rainfall, temperature, evapotranspiration, wind speed, sunshine hours, relative humidity and runoff. In order to determine the basic hydrologic parameters, meteorological data was collected from the stations in and around the lake Awassa catchment. The amount of groundwater that is currently being used for domestic and non-domestic purposes in the basin is 17.8 million cubic meter. The net total amount of water that is actually available to recharge the groundwater circulation within the Lake Awassa catchment is 218.79 million cubic meter. Currently, 233 groundwater structures are found developed in different parts of the study area. Out of these 49 are non functional. Among the developed groundwater structures dominantly nonfunctional is hand dug wells, which comprises 29.55% of the total constructed hand dug wells. The hand dug wells are followed by shallow wells (25%), springs (19.75%) and boreholes (10%). Poor management of the constructed schemes, lack of awareness at community level, spare part problems, and construction problems are the major causes of the failure of the groundwater structures. Utilization of groundwater in the functional ones is not conducted on the basis of recommended values that were set based on the hydrogeological parameters during the development of the structures. Discharging hours are increased to satisfy the water demands of different users. Currently, groundwater is developed without groundwater management plan in uncoordinated manner by governmental and nongovernmental organizations and also privately.At present, the amount of natural recharge in the basin is more than the abstraction. The problem is not lack of water; it is rather absence of or poor management. This is mainly due to lack of efficient groundwater management organization at sub-basin level. Management of groundwater resources is crucial for better development and optimum utilization of the groundwater resources of the basin and to avoid any adverse effects. Therefore it is necessary to establish an efficient groundwater management organization that can conduct detailed groundwater management studies of the basin, follow the objectives of the national water resources management policy and also effectively implement.

Keywords: Aquifer ; Ethiopia;Groundwater management; Hydrogeology;Lake Awsasa

DOI: 10.7176/JRDM/75-02

Publication date:May 31^st 2021