Reservoir Sedimentation at Wadi System: Challenges and Management Strategies

Abstract

In this paper, current challenges of reservoir sedimentations are presented along with our achievements to overcome such struggles for long term sustainable management of sediments in dry reservoirs are also addressed. There are several problems of sedimentation in wadi system including decreasing reservoir storage capacity, affecting the groundwater recharges (sediment clogging), increasing the disaster risk of flash floods, and downstream environmental impacts. Two field surveys on Dec 2017 and Sept, 2018 were conducted for Wadi Mijlas in Oman in order to study the sedimentation issues and its impacts on the reservoir capacity and infiltration processes. Several measures have been implemented such as pedon analysis, collecting sediments samples, drone survey, infiltration tests were conducted. The sedimentation volume at the reservoir along Wadi Mijlas was estimated from the sedimentation measure bars installed in the reservoir before the dam constructions. Sediment transport modeling and infiltration modeling were successfully conducted. The results showed that the recharge rate was adversely affected by sedimentation.