Comparison of Digital Elevation Models for Determining the Area and Volume of the Water Reservoir

Abstract

Nowadays, like many other fields, DEM is widely used in the field of hydraulic engineering. In our studies, we compared the DEMs (SRTM, ASTER GDEM v2, and ALOS PALSAR) for the area recommended for the construction of the Shurbulak water reservoir. Contours were developed for all DEMs and were compared with the contours of a topographic map. The contours of the SRTM and ALOS PALSAR closely match with the contours on the topographic map than ASTER. Vertical differences between SRTM, ASTER GDEM2, and ALOS PALSAR products were computed the root mean squared error (RMSE) compared to Ground Control Point (GCP) data. RMSE results show that 3.53 m for ALOS PALSAR, 6.27 m for ASTER and 4.09 m for SRTM. The longitudinal profiles of dams (No. 1 and No. 2) of all DEMs were compared with the data of the design institute - UzGIP. The results of comparing the longitudinal profile of the dam (No. 1 and No. 2) on digital ALOS PALSAR models correspond to the longitudinal profile of dams (No. 1 and No. 2) developed by the design institutes. Viewed as a result of all comparisons (comparison of DEMs and topographic map, computed RMSE, comparison longitudinal profile of the dam) ALOS PALSAR is more accurate than other DEMs. Therefore, we decided to use ALOS PALSAR for the determination of water reservoir area and volume. The area and volume of the reservoir were determined using the digital model ALOS PALSAR.