Flood Hydrology
Extreme flood do occur. Learn more at DamFailures.org |
Hydrology is essential not only in the design of a dam, but also in the feasibility study of a dam and in assessments of the dam into the future as the state-of-the-practice evolves. The three main components of flood hydrology, according to the United States Bureau of Reclamation (USBR) are “(1) hydrometeorology related to probable maximum precipitation determinations, (2) probable maximum flood hydrograph determinations, and (3) statistics and probabilities relating to the magnitude and frequency of flood flows”.[1]
“One of the most common causes of dam failures is the inability to safely pass flood flows. Failures caused by hydrologic conditions can range from sudden failure, with complete breaching or collapse of the dam, to gradual failure, with progressive erosion and partial breaching”.[2] Therefore, hydrologic studies are among the most important sources of information when it comes to dam safety.
Methodologies
Examples
Learn more about the occurrence of extreme floods at DamFailures.org
Best Practices Resources
Technical Release 210-60: Earth Dams and Reservoirs, NRCS, 2019
Selecting and Accommodating Inflow Design Floods for Dams (FEMA P-94), FEMA, 2013
Hydrologic Engineering Requirements for Reservoirs (EM 1110-2-1420), USACE, 1997
Flood Hydrology Manual, USBR, 1989
Trainings
Dam Owner Academy: Extreme Rainfall Events
Citations:
Revision ID: 5994
Revision Date: 12/19/2022