LAUSR

In river basins with water storage facilities, the availability of regularly-updated information on reservoir level and capacity is of paramount importance for the effective management of those systems. Yet, for the vast majority of reservoirs around the world, storage levels are either not measured or not readily available due to financial, political or legal considerations. This paper proposes a novel approach using Landsat imagery and Digital Elevation Models (DEM) to retrieve information on storage variations in inaccessible regions. Unlike existing approaches, the method does not require any in situ measurement and is appropriate to monitor small, and often undocumented, irrigation reservoirs. It consists of three recovery steps: (i) a 2D dynamic classification of Landsat spectral bands information to quantify the surface area of water, (ii) a statistical correction of DEM data to characterize the topography of each reservoir and (iii) a 3D reconstruction algorithm to correct for clouds and Landsat 7 Scan Line Corrector failure. The method is applied to quantify reservoir storage in the Yarmouk basin in Southern Syria, where ground monitoring is impeded by the ongoing civil war. It is validated against available in situ measurements in neighboring Jordanian reservoirs. Coefficients of determination range from 0.69 to 0.84, and the average relative error from 3 % to 35 % for storage estimations on six Jordanian reservoirs with maximal water surface areas ranging from 0.59 km 2 to 3.79 km 2 .