Can the discharge of a hyperconcentrated flow be estimated from paleoflood evidence?
Article first published online: 28 DEC 2011
© 2011 by the American Geophysical Union
This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
Water Resources Research
Volume 47, Issue 12, December 2011
How to Cite
2011), Can the discharge of a hyperconcentrated flow be estimated from paleoflood evidence?, Water Resour. Res., 47, W12535, doi:10.1029/2011WR010380., , , , and (
- Issue published online: 28 DEC 2011
- Article first published online: 28 DEC 2011
- Manuscript Accepted: 11 NOV 2011
- Manuscript Revised: 7 NOV 2011
- Manuscript Received: 5 JAN 2011
- hyperconcentrated flow;
- mountain torrent;
- paleostage indicator;
- peak discharge
 Many flood events involving water and sediments have been characterized using classic hydraulics principles, assuming the existence of critical flow and many other simplifications. In this paper, hyperconcentrated flow discharge was evaluated by using paleoflood reconstructions (based on paleostage indicators [PSI]) combined with a detailed hydraulic analysis of the critical flow assumption. The exact location where this condition occurred was established by iteratively determining the corresponding cross section, so that specific energy is at a minimum. In addition, all of the factors and parameters involved in the process were assessed, especially those related to the momentum equation, existing shear stresses in the wetted perimeter, and nonhydrostatic and hydrostatic pressure distributions. The superelevation of the hyperconcentrated flow, due to the flow elevation curvature, was also estimated and calibrated with the PSI. The estimated peak discharge was established once the iterative process was unable to improve the fit between the simulated depth and the depth observed from the PSI. The methodological approach proposed here can be applied to other higher-gradient mountainous torrents with a similar geomorphic configuration to the one studied in this paper. Likewise, results have been derived with fewer uncertainties than those obtained from standard hydraulic approaches, whose simplifying assumptions have not been considered.