Jonathan Harris currently acts as the National Practice Leader for Dam Safety and Risk at Schnabel. He has over 27 years of experience specializing in geotechnical engineering, embankment dam design, seismic engineering, dam safety, and risk analysis. He spent 11 years with the Bureau of Reclamation, working at the Technical Service Center as a Technical Project Lead. Jonathan has conducted numerous dam safety assessments for Reclamation, FERC licensees, and other hydropower owners in the United States and other countries. He spent three years working in New Zealand performing dam safety and risk assessments within New Zealand and other countries.

Jonathan has performed as a facilitator and subject matter expert for qualitative and quantitative risk analyses for numerous dam facilities. He has actively been involved in providing training for dam safety and risk analysis for over 15 years and is currently part of the United States Society on Dams risk-informed decision making (RIDM) training development leadership team and helped organize the semi-quantitative risk analysis RIDM training.

Jonathan has overseen numerous embankment dam projects for new and existing structures including site investigation, design, construction, and remediation. He has also been involved with many dam safety assessments for a variety of dam structure types and appurtenant structures, including embankments, spillways, and concrete dams.

Mr. Scott received his B.S. and M.S. degrees in Civil Engineering from the University of Colorado, Boulder. He started his career with the Bureau of Reclamation in 1976, where he worked for 34 years before joining the U.S. Army Corps of Engineers Risk Management Center as Lead Civil Engineer, where he worked through 2018. He has been involved with design, analysis, and construction of dams and dam safety projects, as well as the development and application of potential failure mode analysis and risk analysis for dam safety. He served on several review panels for Bureau of Reclamation and Corps of Engineers dam construction and dam safety projects. He has authored over 35 technical papers in journals and conference proceedings related to dam safety and dam engineering. He is now retired from Federal service, but continues to consult on a limited basis. 

Bill has 42 years’ experience in hydraulic and structural engineering designs for concrete dams and appurtenant structures, with the Bureau of Reclamation. While with Reclamation, he served as a technical specialist and design team leader for numerous water resource projects. In the later part of his career, he served as a member of Reclamation’s three-person Risk Advisory Team, which was responsible for developing additional risk analysis methodologies and providing training for Reclamation.

staff. Bill has particular expertise in concrete dam and spillway modifications, including: project planning and design coordination; analysis and design of structural modifications; review of design drawings and specifications; construction support; and risk analysis methodologies and facilitation. He has written numerous papers focused on dam safety evaluations and dam safety modifications. He was a lead author on a Reclamation manual focused on drains for dams and on a FEMA manual focused on flood overtopping protection for dams. For the past two years, he has worked as a consultant in the role of senior technical advisor.

Mr. Lund has over 40 years of experience in dam safety, design, including hydraulic structure design of spillways, outlet works, and appurtenant structures, comprehensive structural analyses of concrete dams (static and dynamic analyses utilizing both linear and non-linear methodologies), field investigations, and construction.  Early in his career Mr. Lund worked as a design engineer on numerous spillways, water conveyance systems, and outlet works for the Bureau of Reclamation.  He has work in the private sector for over the past over 30 years Mr. Lund and gained experience in the design, analysis, and evaluation of all types of concrete dams. 

Mr. Lund has been working with potential failure modes and risk for over 20 years, and currently serves as the independent consultant and of board of consultant review member for many FERC Projects.  

Phoebe Percell-Taureau has over 20 years of experience in dam and levee safety, security, emergency management. She has led the two largest dam safety programs in the world, both for the US Bureau of Reclamation and the US Army Corps of Engineers. Her focus is not only on getting the engineering right to defend decisions, but also in building the case for those decisions in a manner that is relatable and understandable for non-technical audiences to get behind. This has only been possible through developing the technical expertise in dam engineering, structural design and analysis, risk analysis, risk-informed design. She spent approximately 15 years on her career in the Technical Services Center of the US Bureau of Reclamation working on highly technical challenges mostly related to concrete dams, seeking to understand the complex performance of gravity, arch, and buttress dams under normal operating conditions, floods, and earthquakes and then taking that understanding into a risk environment to evaluate whether or not the performance of the structure met an acceptable level for risk to the public. Sometimes it was not acceptable and Phoebe would then incorporate that same understanding of risk to inform the design for a modification or change to operations. In private sector she used those skills to advise dam owners on the best path forward for their challenges.

AdamToothman is a registered professional engineer with more than 22 years of civiland structural engineering experience with a focus in design and analysis of concretedams and hydraulic structures.  He workedfor 4 years with the U.S. Army Corps of Engineers in the HuntingtonDistrict.  He then worked for 15 yearswith the U.S. Bureau of Reclamation at the Technical Service Center in Denver,CO where he was a design team project manager for a number of final designprojects including spillway modifications, outlet works replacement, and damraise projects all using Risk-Informed Design. He was the team lead for numerous dam safety Issue Evaluations,Comprehensive Dam Reviews, risk evaluation studies, and author of quantitativerisk analysis reports.  Adam joined HDR in2022 in their Denver, CO office where he is a technical lead for the design of3 new RCC dam projects, and has been the subject matter expert for semi-quantitativerisk analyses for local, state, and other federal government agencies.  He has a Bachelor of Science degree in CivilEngineering from West Virginia University and a Master of Engineering degree inCivil Engineering from Virginia Tech.

Mr. Scott received his B.S. and M.S. degrees in Civil Engineering from the University of Colorado, Boulder. He started his career with the Bureau of Reclamation in 1976, where he worked for 34 years before joining the U.S. Army Corps of Engineers Risk Management Center as Lead Civil Engineer, where he worked through 2018. He has been involved with design, analysis, and construction of dams and dam safety projects, as well as the development and application of potential failure mode analysis and risk analysis for dam safety. He served on several review panels for Bureau of Reclamation and Corps of Engineers dam construction and dam safety projects. He has authored over 35 technical papers in journals and conference proceedings related to dam safety and dam engineering. He is now retired from Federal service, but continues to consult on a limited basis. 

Bill has 42 years’ experience in hydraulic and structural engineering designs for concrete dams and appurtenant structures, with the Bureau of Reclamation. While with Reclamation, he served as a technical specialist and design team leader for numerous water resource projects. In the later part of his career, he served as a member of Reclamation’s three-person Risk Advisory Team, which was responsible for developing additional risk analysis methodologies and providing training for Reclamation.

staff. Bill has particular expertise in concrete dam and spillway modifications, including: project planning and design coordination; analysis and design of structural modifications; review of design drawings and specifications; construction support; and risk analysis methodologies and facilitation. He has written numerous papers focused on dam safety evaluations and dam safety modifications. He was a lead author on a Reclamation manual focused on drains for dams and on a FEMA manual focused on flood overtopping protection for dams. For the past two years, he has worked as a consultant in the role of senior technical advisor.

Mel Schaefer is a Civil Engineer with over 35 years of experience in dam safety engineering specializing in analyzes of extreme storms and floods for assessing the hydrologic adequacy of dams and spillways. He began his career as a staff hydrologist with the Washington State Dam Safety Program and became Head of the State Dam Safety Program in 1990 where he managed a group of hydrologic, geotechnical and structural engineers. During his 7-year tenure as head of the Dam Safety Program, he developed the risk-based design/analysis methods and performance standards and regulations for dam safety that are in-use today. He was involved in the inspection, flood analyses and remediation of over 100 dams while with the Dam Safety Program.

In 1997, he started a private consulting firm, MGS Engineering Consultants Inc. which specializes in surface water hydrology, particularly probabilistic and risk applications of extreme precipitation and floods. Over the 20-years in private practice, he has conducted probabilistic flood analyses for use in risk analyses for over 40-dams for BC Hydro, US Bureau of Reclamation, US Army Corps of Engineers, Southern California Edison, and the Tennessee Valley Authority including notable projects such as Mica Dam on the Upper Columbia River BC, Folsom Dam on the American River CA, and Mammoth Pool Dam on the San Joaquin River CA. He has conducted large-scale regional precipitation-frequency (PF) studies for the province of British Columbia; the states of Washington and Oregon; a seven State area surrounding the Tennessee River valley; the States of Colorado and New Mexico; central Texas and New Brunswick and States in New England. He has pioneered methods for numerous elements for conducting hydrologic risk analysis including regional PF analysis (SWT climate region method); storm transposition by the OTF and ESTP methods; stochastic generation of watershed PF relationships for synoptic scale mid-latitude cyclones, tropical storms, and remnants, and mesoscale convective storms; and uncertainty analysis.
He is the lead developer for the Stochastic Event Flood Model (SEFM) for computing probabilistic flood loadings and hydrologic hazard curves and L-RAP software for conducting regional precipitation frequency analysis. Both SEFM and L-RAP are commercial software products. He routinely serves on the FERC Board of Consultants and Peer Review teams for review of site-specific PMP and PMF studies and for applications of hydrologic risk.

Mr. France has more than 40 years of experience in engineering consulting and design. Most of Mr. France’s technical work for the past 36 years has focused on dam engineering, and he has been involved in dam safety risk analysis for more than 20 years. His risk analysis work has included serving as a facilitator or subject matter expert on semi-quantitative risk analyses (SQRAs) and full quantitative risk analyses (QRAs) for such clients as the New Mexico OSE, the U.S. Army Corps of Engineers (USACE), the U.S. Department of the Interior, Bureau of Reclamation Reclamation), the U.S. Fish and Wildlife Service, Denver Water, the Colorado Division of Parks and Wildlife, and Aqua Ohio. Mr. France has also completed assignments reviewing risk analyses completed by the USACE and Reclamation. 

His experience in dam safety risk analysis led to his selection as a member of a four-person team that developed a three-day SQRA course for USSD, presented for the first time in October 2019. In addition to his risk analysis work, he has served on senior technical review panels/boards for the USACE, Reclamation, BC Hydro, Brookfield Renewable Energy, and the Lower Colorado River Authority. Mr. France has developed a reputation as one of the leading practitioners in dam engineering and dam safety, which resulted in his selection to lead the six-person team charged with completing a forensic investigation of the 2017 Oroville Dam spillway incident. He regularly publishes papers and makes presentations for conferences of ASDSO, USSD, and ASCE, and he has twice received the prestigious President's Award from ASDSO for his contributions to dam safety. He also regularly lectures at courses on dam safety topics.

Matt Montgomery received a bachelor's degree in civil engineering and a master's degree in environmental engineering from the honors college at the University of Tennessee, Knoxville. Mr. Montgomery is currently a civil engineer in the Hydrologic Impacts and Risk Evaluation (HIRE) group at Tennessee Valley Authority (TVA) where he performs hydrologic and hydraulic modeling largely in support of risk assessment for dams in the TVA portfolio. Mr. Montgomery contributes to the determination of hydrologic hazard probabilities by performing statistical analyses on historical data and stochastic model output. In support of downstream consequences assessment, he performs dam breach hydraulic modeling and downstream consequences modeling.

Robb has been a professor in the Civil and Environmental Engineering Department at California Polytechnic State University, San Luis Obispo, since 2005.  He earned a Ph.D. from U.C. Berkeley in the field of geotechnical earthquake engineering, with minors in engineering seismology and structural reliability. His research and consulting focuses on the physics and probability of natural hazards such as; strong ground motions, seismic soil liquefaction, surface fault rupture, seismic induced landslides, debris flow, and others.  His teaching includes undergraduate and graduate courses in; geotechnical engineering, engineering risk analysis, geological engineering, earthquake engineering, and others.  He has been a member of ten earthquake reconnaissance teams traveling to Nepal, Japan, Chile, Alaska, Turkiye, India, Mexico, and around California.  Robb was appointed a Fulbright Scholar to Chile for 2017-2020 and is currently an editor for the ASCE Journal of Geotechnical and Geoenvironmental Engineering.

Ross Boulanger is a consulting civil engineer and a Distinguished Professor Emeritus in the Department of Civil and Environmental Engineering at the University of California, Davis. He received his Bachelor's degree from the University of British Columbia in 1986, followed by his Master's and Doctoral degrees from the University of California at Berkeley. His tenure at UC Davis from 1992 through 2023 included 14 years as Director of the Center for Geotechnical Modeling and its national shared-use centrifuge facilities. He has over 300 publications, primarily related to liquefaction and its remediation, seismic performance of dams and levees, and seismic soil-structure interaction. His consulting activities are primarily related to dam, tunnel, and infrastructure projects. His honors include the Casagrande Award, Huber Prize, Norman Medal, and Peck Award from ASCE, the Ishihara Lecture from ISSMGE, and election to the US National Academy of Engineering.

Dr. Ellen M. Rathje is the Janet S. Cockrell Centennial Chair in the Department of Civil, Architectural, and Environmental Engineering and a Senior Research Scientist at the Bureau of Economic Geology (BEG) at the University of Texas at Austin, USA. Her research interests include seismic site response analysis, seismic slope stability, earthquake-induced ground failure, and remote sensing.  She has published over 100 papers on these topics and has supervised the research of over 30 graduate students. Her research has been funded by the the U.S. National Science Foundation, U.S. Geological Survey, the U.S. Nuclear Regulatory Commission, the State of Texas, and the United Nations Development Program.

Dr. Rathje is the Principal Investigator for the development of the DesignSafe cyberinfrastructure for the NSF-funded Natural Hazards Engineering Research Infrastructure (NHERI). She is part of the Leadership Team for the TexNet Seismic Monitoring Program, housed at the Bureau of Economic Geology of UT. She also is a founding member and previous Co-Chair of the Geotechnical Extreme Events Reconnaissance (GEER) Association, the pre-eminent organization in the world coordinating geotechnical investigations after extreme events, such as earthquakes and floods.  

Much of her consulting work is associated with site response and seismic hazard studies for nuclear facilities around the globe, including the Thyspunt Nuclear Site in South Africa, four existing nuclear power plants in Taiwan operated by Taipower, and multiple nuclear facilities at the Idaho National Laboratory.

She is currently a member of the Board of Directors of the International Association for Earthquake Engineering (IAEE) and also a member of the NSF Advisory Committee for Cyberinfrastructure (ACCI).  She has previously served on the Committee on Geological and Geotechnical Engineering (COGGE) for The National Academies of Sciences, Engineering, and Medicine, the Board of Directors for the Earthquake Engineering Research Institute (EERI), and the USGS Scientific Earthquake Studies Advisory Committee.

Dr. Rathje has been honored with various research awards, including the 2022 Peck Award and Lecture from the Geo-Institute of the American Society of Civil Engineers (ASCE), the 2018 William B. Joyner Lecture Award from the Seismological Society of America and EERI, the Huber Research Prize from ASCE in 2010, the Hogentogler Award for outstanding paper from ASTM Committee D18 in 2010, the Shamsher Prakash Research Award in 2007, the Shah Innovation Prize from EERI in 2006, and the Casagrande Award from ASCE in 2002. She was elected Fellow of the American Society of Civil Engineers in 2016.

Pete serves as a senior project manager for Ayres with a primary focus on improving performance of hydraulic structures and completing federal dam inspections. In the dam removal field, Pete managed the 2015 design and removal of the 257kW Gordon Hydro Dam (33 feet high with less than 40,000 cubic yards of sediment) and the 2012 design and removal of the 306kW Grimh Hydro Dam (30 feet high with 115,000 cubic yards of sediment).  He has consulted on more than ten dam removal projects.

Thomas Hepler has nearly 36 years of experience with the Bureau of Reclamation, Department of Interior, in hydraulic and structural engineering design for concrete dams, spillways, and outlet works. He has performed dam safety inspections on numerous large concrete dams including T. Roosevelt Dam Raise and Clear Lake Replacement Dam. Experienced in potential failure mode analysis (PFMA) and risk analysis for dams and Engineer of Record for the removal of Elwha and Glines Canyon Dams, and of several smaller dams on the West Coast. Co-author of guidance documents on overtopping protection for dams, dam decommissioning, and roller-compacted concrete. Current member of Technical Representative team for removal of four hydroelectric dams on the Klamath River. As a Senior Consultant for Schnabel, currently perform PFMA and risk analyses for municipal governments and utilities, and Part 12 inspections for FERC licensees. Have served on Value Engineering teams and Independent Review panels. Member ASCE, USSD, and ASDSO.

Jared Vegrzyn is a hydraulic engineer with WEST Consultants, Inc..  He has a strong educational background in analysis and application of physical and mathematical relationships related to hydrology and hydraulics from the University of Illinois at Urbana-Champaign. His experience includes hydraulic and hydrologic modeling and river geomorphology. a

Eric is a registered professional engineer working as a dam and levee consultant specializing in risk and safety programs. He retired from the Corps of Engineers after almost 40 years of service where he led the agency Dam and Levee Safety Programs as well as the National Levee Safety Program. He has engineering degrees from Clemson University (1983) and Oklahoma State University (1989).  Currently, he is the principal of Halpin Consulting LLC where he works internationally with clients in the dam, levee, and mining industry.  

Miles Yaw is a Civil Engineer in the Tennessee Valley Authority’s River Management unit. He manages TVA’s probabilistic hydrology, downstream consequences, and paleoflood hydrology programs, and also serves as a subject matter expert for hydraulics and hydrology for Dam Safety Inspections, Risk Assessments, and Modification Studies. He currently serves as the Young Professional Vice Chairman of the USSD Hydraulics and Hydrology committee. Prior to TVA, Mr. Yaw worked in consulting, focusing on river mechanics, sediment transport, and fluvial geomorphology. During that time, Mr. Yaw performed sediment transport studies on rivers across the United States to help dam owners understand downstream morphological impacts of existing and proposed operations. Mr. Yaw also provided direct development and testing support for the sediment transport routines in HEC-RAS 5.x. He holds a Master’s degree in Civil Engineering from Colorado State University and a BS in Civil Engineering from Washington State University. He currently lives in Knoxville, TN with his wife and three children.

Ryan Clark is a hydraulic engineer with the USACE Dam Safety Modification Center (DSMC).  While the center is located in LRH, Mr. Clark sits virtually in the Nashville District.  Prior to working for the DSMC he worked in the Water Resources Section of the Hydrology and Hydraulics Branch of the Nashville District for over 8 years.   With over 10 years of flood risk experience, he currently works on hydrologic hazards and risk studies for the USACE Dam and Levee Safety Program.  He received his B.S. and M.S. in Civil and Environmental Engineering from Tennessee Technological University as well as a M.S. in Risk Management from Notre Dame of Maryland University. He is a registered professional engineer in the State of Tennessee.  Besides work, he enjoys watching the Cubs and Titans, getting outdoors as much as possible with his family, and enjoying a nice glass of bourbon with his friends.

Carolyn J. Pearson is a Hydrologic Engineer at the U.S. Army Corps of Engineers Risk Management Center.  Carolyn is a registered professional engineer in the state of Missouri with over 11 years of experience in hydraulic and hydrology analysis, design, and risk assessment in the dam and levee safety programs. She is currently an RMC Regional Hydrology Lead providing technical guidance and oversight on national Dam and Levee Safety studies. She has a B.S. in Civil Engineering from Missouri University of Science & Technology, a B.S. in Chemistry and Secondary Education from Graceland University, an M.S in Civil Engineering (Water Resources & Environmental) from the University of Missouri-Kansas City, and an M.S. in Risk Management from the Notre Dame University of Maryland.  She currently lives near the front range of the Rocky Mountains in Littleton, CO.