Groundwater Flow Modeling of WejaRiver Catchment By Using MODFLOW

Abstract

The Weja River Catchment Study Area Located in the Central Ethiopia Rifty Valley to West of Lake Ziway and Total Catchment Study Area 967S.km Was Simulated Study Area Ground Water Flow Modeling by Using MODFLOW USGS-2005(MODFLOW USGS-2005 Version, 3.1). The aims of the Modeling Ground Water Flow MODFLOW Quantify Hydraulics and Aquifer Parameters of Study Area by Existed Data Collections from Desk of Office and Minster Sector and giving Emphasis Well and Fields Data that Inputs for Raw Data for MODFLOW Modeling and The approaches to achieve the objective of the research involve data collection, analysis and synthesis with understanding the flow system of the Study Area. Sensitivity analysed for Ground Water Flow System and Aquifer Parameters Were Time Steps Response for Natural and Man Mad Influence of Study Area Stream Flow, The Scenarios Analysed the Study Area System of Flow for Ground Water Extraction and Natural Drain System (spring) Simulated time Steps Response that Due to Over Extraction of Discharge the Ground Water Flow System Were Time Steps Transited Flow From Steady State to Unsteady State Ground Water Flow System and Drawn Dawn Was Increased Time Steps. MODFLOW USGS-2005 Analysed the Hydraulics Conductivity of Ground Water Flow System Were Increased Time Steps and Porosity and Other Most Aquifer Parameters Were Decreased Due to Increased Ground Water Outflow and Over Extraction of Ground Water Storage Reservoir. The Study Area Source of Stream Flow Were from Ground Water Storage Reservoir Outflow to Surface Flow System in the Form of Stream Flow or springs. Therefore Scenarios Simulated that Due to Over Extraction of Ground Water Level of Ground Water Decline and Drown Dawn Were Increased Time Steps Due to that Ground Water Outflow System by Spring Outflow Were Decreased and the Study Area Surface Stream Flow Were Time Steps Dries Stream Were Formed on Weja River Catchment