Next Article in Journal
The June 2016 Australian East Coast Low: Importance of Wave Direction for Coastal Erosion Assessment
Next Article in Special Issue
Soil Moisture for Hydrological Applications: Open Questions and New Opportunities
Previous Article in Journal
Groundwater Level Changes Due to Extreme Weather—An Evaluation Tool for Sustainable Water Management
Previous Article in Special Issue
Space–Time Characterization of Rainfall Field in Tuscany
Article Menu
Issue 2 (February) cover image

Export Article

Open AccessFeature PaperArticle
Water 2017, 9(2), 120;

From Surface Flow Velocity Measurements to Discharge Assessment by the Entropy Theory

Research Institute for Geo-Hydrological Protection, National Research Council, Via Madonna Alta 126, 06128 Perugia, Italy
Author to whom correspondence should be addressed.
Academic Editor: Ataur Rahman
Received: 22 December 2016 / Revised: 31 January 2017 / Accepted: 9 February 2017 / Published: 14 February 2017
(This article belongs to the Special Issue Advances in Hydro-Meteorological Monitoring)
Full-Text   |   PDF [2411 KB, uploaded 14 February 2017]   |  


A new methodology for estimating the discharge starting from the monitoring of surface flow velocity, usurf, is proposed. The approach, based on the entropy theory, involves the actual location of maximum flow velocity, umax, which may occur below the water surface (dip phenomena), affecting the shape of velocity profile. The method identifies the two-dimensional velocity distribution in the cross-sectional flow area, just sampling usurf and applying an iterative procedure to estimate both the dip and umax. Five gage sites, for which a large velocity dataset is available, are used as a case study. Results show that the method is accurate in simulating the depth-averaged velocities along the verticals and the mean flow velocity with an error, on average, lower than 12% and 6%, respectively. The comparison with the velocity index method for the estimation of the mean flow velocity using the measured usurf, demonstrates that the method proposed here is more accurate mainly for rivers with a lower aspect ratio where secondary currents are expected. Moreover, the dip assessment is found more representative of the actual location of maximum flow velocity with respect to the one estimated by a different entropy approach. In terms of discharge, the errors do not exceed 3% for high floods, showing the good potentiality of the method to be used for the monitoring of these events. View Full-Text
Keywords: streamflow measurements; surface velocity; maximum velocity; entropy; ADCP; LSPIV; SVR streamflow measurements; surface velocity; maximum velocity; entropy; ADCP; LSPIV; SVR

Figure 1

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited (CC BY 4.0).
Printed Edition Available!
A printed edition of this Special Issue is available here.

Share & Cite This Article

MDPI and ACS Style

Moramarco, T.; Barbetta, S.; Tarpanelli, A. From Surface Flow Velocity Measurements to Discharge Assessment by the Entropy Theory. Water 2017, 9, 120.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics



[Return to top]
Water EISSN 2073-4441 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top