Subsurface Dams as a Solution for Supplementary Recharge and Groundwater Storage in Karst Aquifers in Arid Areas

Abstract

Subsurface dams could be an optimal solution for storing floods or waters of temporary streams in countries with arid and semi-arid climatic conditions. Many such structures are already completed in the Middle East and northern and eastern African countries, and many new locations require feasibility assessment and construction if found appropriate. Two types of dams are common: one built in the karst (for direct recharge), and the other into the karst connected alluvial aquifer (for indirect recharge). The former is relatively rare due to its more complicated construction; the latter has been applied more often. This article discusses some positive experiences with such dams in northern Iraq, Algeria and Ethiopia and advantages of subsurface dam application in Somalia and Iraq, but it also explores uncertainties which end-users may face if the engineering design is not prepared based on results of a proper research programme.