Estimation and uncertainty of remote-sensing-based Depth-Area-Volume (DAV) relationships

ABSTRACT

Artificial reservoirs are the only reliable source of water resources in most of the brazilian semiarid region. Their water availability depends on the hydrology and the climate, but also on the geometry of the reservoir, expressed usually in terms of Depth-Area-Volume (DAV) curves. However, for most public reservoirs in northeastern Brazil, this information is often outdated or inconsistent, because of reservoir silting and the lack of systematic updating and assessment of actual storage capacity. . In this work, we present a quick and low-cost statistical procedure to assess reservoir volume, based on temporal sequences of satellite imagery and water level monitoring. Two methods are evaluated to quantify the confidence intervals from these estimates. The results were validated for a reservoir where a recent and reliable bathymetry is available. The approach was then used to estimate the volume of a reservoir in northern Minas Gerais, which storage capacity is uncertain.

Keywords:  Depth-volume; Remote sensing; Bathymetry