Abstract

Accurate measurement of water levels and variations in lakes and reservoirs is crucial for water management. The retrieval of the accurate variations in water levels in lakes and reservoirs with small widths from high-resolution synthetic aperture radar (SAR) images such as the TerraSAR add-on for Digital Elevation Measurements (TanDEM-X) and COnstellation of small Satellites for the Mediterranean basin Observation (COSMO-SkyMed) are presented here. A detailed digital surface model (DSM) for the upstream face of the dam was constructed using SAR interferometry with TanDEM-X data to estimate the water level. The elevation of the waterline below that of the interferometric SAR (InSAR) DSM was estimated based on upstream face modeling. The waterline boundary detected using the SAR Edge Detection Hough Transform algorithm was applied to the restored DSM. The SAR-derived water level variations showed a high correlation coefficient of 0.99 and a gradient of 1.08 with the gauged data. The difference between the gauged data and SAR-derived data was within ±1 m, and the standard deviation of the residual was 0.60 m. These results suggest that water level estimation can be used as an operational supplement for traditional gauged data at remote sites.

Highlights

  • Dams and impoundments have been built to enable the storage of water necessary during the dry season and to control flooding, recreation, navigation, and the generation of hydropower [1,2]

  • The dedescending image shows foreshortening on the upstream face of the dam that may cause scending on thewhile upstream face of the dam shows that may squeezingimage of theshows fringesforeshortening on the dam surface, the ascending image the cause slope squeezing of the fringes on the dam surface, while the ascending image shows the slope of the upstream face well

  • The TDX interferometric SAR (InSAR) digital surface model (DSM) generated from the ascending of the upstream face13well

Read more

Summary

Introduction

Dams and impoundments have been built to enable the storage of water necessary during the dry season and to control flooding, recreation, navigation, and the generation of hydropower [1,2]. Water level monitoring is essential because lakes and reservoirs are proxies for understanding global climate change [3]. Once the water volume has been determined and combined with precipitation, evaporation, and inflow, the water balance of lakes and reservoirs can be used to estimate the outflow [4]. The large uncertainties associated with projected precipitation changes make it difficult for the responsible agencies to perform water management practices, such as water allocation and water release strategies. Accurate measurement of water levels and monitoring of variations in lakes and reservoirs are essential for equitable water allocation to water management and ecosystem services and to improve the understanding of the impacts of climate change [5,6].

Objectives
Methods
Results
Discussion
Conclusion
Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call