Ryan Clark

• Served as HH team lead on Dam Safety projects including formulating estimates and schedules for multiple risk assessments. All projects have their own unique problems and challenges, but I engaged with experts to resolve challenges and maintain schedule, scope, and quality. For Clemson Dam IES, these structures include two diversion dams and a diversion dike, creating a continuous loading condition from the Hartwell Lake impoundment. Historically, dam safety risk assessments for these structures have relied on the hydrologic hazard curve of Hartwell Dam under the assumption of a level-pool extending to the Clemson structures. A two-dimensional hydraulic model was developed to evaluate the level-pool assumption and analyze rare to extreme flood events. The results revealed that the level-pool assumption fails beyond an inflection point during large inflow events, leading to increased pool levels and hydraulic loading at the Clemson diversion dams and dike compared to Hartwell Dam. This critical insight necessitated transforming the hydrologic hazard curve using RMC-TotalRisk from Hartwell Dam to the Clemson structures. Using the transformed hydrologic hazard curve, the Clemson structures face greater hydraulic loadings than previously understood, improving the understanding of risk at the facility, which is currently undergoing an issue evaluation associated with internal erosion failure potential modes.
• I have maintained my technical qualifications (PE) to meet the requirements for HH as a national expert. I attended and
  co-developed a paper/presentation at the 2024 ASDSO Conference on a successful paleoflood study for the Kootenai River in Montana for the Libby Dam QRA. The conference provided a great opportunity to network and build on technical advances in the HH and Dam Safety CoP. I routinely attend HH and Dam Safety CoP webinars to build on my professional development. I develop at least 1 abstract annually to submit to national level dam safety forums as both presentations and technical papers. This year I have a paper accepted for the USSD 2025 Conference, submitted another abstract to ASDSO 2025, and am working on a submittal for a third paper to ANCOLD/NZCOLD 2025 conference. All paper submissions go through internal and external reviews and are based on cutting
  edge work I have completed. I have also attended several Dam Safety trainings taught by the RMC and apply the lessons
  learned/techniques developed in these trainings to my everyday practice. I was selected to present at the first annual HEC-RAS Users group meeting at HEC in April of 2024 and presented on 2D HEC-RAS applications in the Dam Safety CoP. I helped update and teach DLS 114 in Lakewood, CO this year, where we had a 16% pass rate on the pre-exam to a 100% pass rate on the final exam. I am also a part of a team tasked with developing a new DLS course for Paleoflood Analysis this FY. All presentations/workshops have been developed and are in review.

Served as H&H team member and/or risk cadre member for multiple Dam Safety Projects with technical oversight and formulating/monitoring estimates, schedules, and progress. Served as Technical Lead for Projects include Willamette River Basin Regional Tier 2 Paleoflood Analysis, Everett & Hopkinton Dam(s) Higher Level 2D PMF Update and Hydrologic Loading, and Libby Dam QRA efforts including a Paleoflood analysis and hydrologic loading update. All projects have been complete or are within budget and of the highest quality. The Everett/Hopkinton Dam(s) PMF update was unique with 2 reservoirs in adjacent watersheds whose pools combine with high stages and used the most up to date modeling which including using the new spatial precipitation grids inside the 2D domain of the model as well as using RMC-RRFT, HEC-HMS, and RMC-TotalRisk to develop the hydrologic loading for the IES. Served as technical oversight for numerous Dam Safety Projects including the Kinzua Dam Safety Modification Study, White River 2D PMF and Paleoflood analysis, Denison Dam IES, John Martin 2D PMF update, Canyon Dam 2D PMF Update, and several more projects. This includes assisting with the estimates, schedules, and technical processes.

Advanced the state of H&H Dam Safety practice as team member who developed two H&H Dam Safety trainings for the international dam safety efforts for the country of Laos. This includes HEC-HMS and HEC-RAS trainings for dam safety. These trainings are meant as intro into H&H for dam safety and should lead into higher level courses for how H&H and flood hazard is incorporated into risk assessments. Trainings include real world projects to the country of Laos as well as use of the Mekong River HMR. Delivered H&H products to advance the state of practice for H&H including the development of flood inundation mapping for the Country of Laos to be used in the nation’s first emergency action plans for a dam break. Developed and presented two technical papers on state-of-the-art applications in the H&H Dam Safety Community for the 2022 and 2023 USSD conferences as well as the 2024 ASDSO conference. Currently tasked with developing a DLS course for Paleoflood Analysis as well as developing an accompanied guidance document.

Delivered a multitude of H&H products for projects across the nation. Projects served as technical lead include Libby Dam QRA, FE Walter Dam Base Level PMF Update, J Percy Priest Base Level PMF Update, RD Bailey Base Level PMF Update, Mojave Dam Phase 2 Paleoflood analysis, and Mojave Dam Higher Level PMF Update. These projects have unique and complex technical issues that needed a higher-level study conducted with state-of-the-art modelling practices. For example, Mojave Dam is utilizing 2D hydrodynamic routing to develop the PMF Update. This project required this higher level PMF because it will be used in the risk informed design for a dam modification study. Have served as H&H team member in support of SQRA and QRA development. These involve updating PMP/ PMF, loading curve analysis, consequence analysis, and probable failure mode determination. Each project has unique qualities, and these challenges were met and solved using various modelling methods and techniques. Have previously and continue to lead teams in developing hydraulic and hydrologic products used by engineers and planners for dam safety projects across the region and nation. This includes the preparation or oversee preparation of, government estimates, scopes of work, and requests for proposals.

Routinely mentor hydraulic and hydrologic engineering specialist working for entities across the country, including other centers and districts. This includes mentoring follow engineers in the developing hydraulic and hydrologic products used by engineers and planners for dam safety projects across the region and nation.

Responsibilities as a lead H&H modeler for the Nashville district water resources section include providing technical leadership for local flood protection, flood risk reduction studies, and planning and dam safety studies. This includes all aspects of hydrology and hydraulics (H&H) that support the evaluation and design with respect to spillway and outlet works capacity and dam failure analysis and have developed hydraulic and hydrologic models and tools to be used for risk reliability analyses to support risk-informed decisions for periodic assessments, issue evaluations, alternative formulation, and dam safety modifications. This includes providing hydraulic and hydrologic engineering input for dam safety risk assessments, potential failure modes analyses, etc. Extensive expertise in hydrologic modeling with the experience of building dozens of hydrologic models with drainage areas ranging from 30 square miles to 30,000 square miles including complex reservoir operations and snowmelt simulations. Hydraulic steady and unsteady-state numeric modeling for large reservoir and riverine systems. Extensive utilization of GIS technology in H&H study and analysis.

Served as H&H technical modeler for the Sava River Flood Study which is an international study with cooperation from four European nations. Served as H&H engineer for Cordell Hull Lock and Dam and Dale Hollow Dam PA’s. Served as project lead/engineer for Section 205 flood reduction study in Cleveland, TN. Duties for this project included overseeing and developing theoretical frequency flood discharges with stages for natural (existing) and future conditions on over 85 miles of streams (including developing floodways. Project included developing design floods for multiple-purpose water control structures, local protection works (levees and flood walls), and channel improvement projects. Developed dozens of hydrologic and hydraulic models for Metro Nashville flood preparedness and served as project engineer for Section 205 flood reduction studies in Davidson County.