News & Events
In recognition of the need to improve flooding risk assessment for dam and levee breach evaluations, Brent Travis, Ph.D., P.E.; Gyan Basyal; and Bryan Wahlin, Ph.D., P.E., of WEST, developed new software that directly incorporates probabilistic aspects of all major components consistent with Monte-Carlo type simulations. The resulting product, named SimRAS, is a multipurpose GUI based HEC-RAS simulation tool, written in Python language utilizing reliable and well tested libraries. In addition to dam and levee break studies, SimRAS can also be used for floodplain delineation and uncertainty analysis, and provides sophisticated post-processing including statistical analyses and direct floodplain mapping. As a parallel project to SimRAS, a simplified closed form mathematical model was also developed from first principles in order to predict 2-dimensional floodwave propagation due to levee breaks, thus allowing rapid risk assessment of flooding at any point of interest in the floodplain. As a further test of their capabilities, both the SimRAS and the simplified model were then used to assess hazard risk at an area of interest within the overflow floodplain of a major levee. These results were discussed and practical guidelines suggested for how best to utilize both methods for hazard risk assessment due to levee failure. Dr. Travis presented at the American Geophysical Union (AGU) Fall Meeting in Washington, D.C., December 10-14, 2018 with an iPoster and an eLightning talk.
Dr. David C. Curtis, F.EWRI, WEST Senior Vice President, presented a paper coauthored by himself and Dr. Luciana Kindl Da Cunha, WEST Project Manager, at the American Geophysical Union (AGU) Fall Meeting in Washington, D.C., in December. The paper, A Framework for Linking the NWS National Water Model with the US Army Corps of Engineers HEC-HMS Model Parameters, discussed an innovative approach that bridges the gap between HMS event-based modeling and continuous soil moisture accounting approaches. HEC HMS (HMS), developed by the US Army Corps of Engineers (USACE), is one of the most widely used hydrologic modeling programs in the world. Increasingly, HMS is being applied to forecast operations both by the USACE and outside agencies. Historical hydrologic losses were developed for reservoirs in the Ft. Worth District of the USACE. Relationships between HMS initial and continuous loss parameters and soil column moisture conditions in upstream catchments modeled by the National Aeronautics and Space Administration (NASA) were drawn. A spreadsheet tool was developed that incorporates the NASA soil moisture data, continuously updated and publicly available online, to provide improved estimates of initial and continuous loss parameters for HMS in a real-time river forecast environment. Utilizing this approach, two diverse models from the NWS and USACE can be operationally linked in near-real time to improve reservoir operations.
In December Jerry W. Webb, P.E., D.WRE, a registered professional in the state of Tennessee, joined the WEST team after more than 44 years of working for the U.S. Army Corps of Engineers’ (USACE’s) Memphis District, Huntington District, and Headquarters offices, where he served as Principal Hydrologic and Hydraulic Engineer. He was Chief of the Water Resources Engineering Branch in the Huntington District, where he was a key member of the Dam Safety Committee and was responsible for water management activities associated with thirty-five reservoirs and nine navigation locks and dams. As the Hydrology, Hydraulics, and Coastal Community of Practice (HH&C CoP) Leader at the USACE Headquarters in Washington D.C., his duties encompassed all aspects of hydrologic, hydraulic, and coastal engineering. In this position, he was responsible for technical policy concerning design, construction, and maintenance of dams and appurtenant structures. He also served as the Chairman of the Columbia River Treaty’s Permanent Engineering Board Engineering Committee, for which he was responsible for coordinating water control operations in accordance with the Treaty.
Mr. Webb served as an engineering officer for more than 23 years in the Tennessee and West Virginia Air National Guard and retired as a Lieutenant Colonel. He also served as the Senior Advisor to Iraq’s Ministry of Water Resources (MoWR). While in this position supporting Iraq reconstruction, he oversaw more than 12,000 personnel operating the world’s oldest water resources system. In addition, he was the interim Senior Advisor to the Ministry of Environment during January-February 2004.
He served several years as the Hydraulics Committee chair and two terms as a U.S. Society of Dams (USSD) Board member. He was a USACE representative for the Advisory Committee on Water Information (ACWI) and the Hydrology and Sedimentation national subcommittees. He served two terms as a Board member and is Past-President (2014) with the AAWRE and acted as a Department of Defense (DOD) representative to the National Dam Safety Review Board.
WEST was selected to complete dam failure inundation studies related to new California state requirements for the Metropolitan Water District of Southern California, Helix Water District, the Santa Fe Irrigation District, the County of Santa Barbara, and others. Newly enacted California state law that became effective in July of 2017 requires dam owners to prepare an Emergency Action Plan (EAP) for their dams and critical appurtenant structures with deadlines depending on the hazard classification of the dam. Inundation maps will form part of the new EAPs but these must be reviewed and approved by the California Division of Safety of Dams prior to submittal of revised EAPs. WEST is currently working with multiple dam owners to meet the new state requirements and is preparing dam breach inundation studies and revised EAPs.