Speakers: Karl Visser, PE, Freese & Nichols, Dam and Levee Engineer; James McNash, PE, Freese and Nichols, Senior Engineer/Engineer VI

PDHs: This webinar is eligible for 2 PDH credits.

This webinar will focus on estimating erosion potential in earthen or vegetated non-structural spillways, identifying the hydraulic limits of earth and vegetated auxiliary spillways, and developing effective methods for repairing erosion in existing non-structural spillways. Additional considerations include evaluating opportunities to increase the capacity of existing earth and vegetated spillways, as well as identifying structural alternatives for replacing non-structural spillways when improved capacity, reliability, or risk reduction is required.

Key Takeaways:
1. Estimating erosion potential in non-structural spillways.
2. Identifying hydraulic limits for earth/vegetated auxiliary spillways.
3. Repairing erosion in an existing non-structural spillway.
4. Adding capacity to an existing earth/vegetated spillway.
5. Identifying structural alternatives for replacing an earth/vegetated non-structural spillway.

Speakers: John France, PE, JWF Consulting LLC, President

PDHs: This webinar is eligible for 2 PDH credits.Geotechnical laboratory tests are used to understand soil composition and engineering properties to support analysis and design of dams. This webinar will review the common geotechnical laboratory tests used in dam engineering practice. Categories of tests to be discussed include:
• Index tests (gradation analysis, Atterberg limits tests, specific gravity tests, etc.).
• Maximum and minimum density tests.
• Engineering property tests (consolidation tests, permeability tests, direct shear tests, triaxial tests, etc.)

The purpose and characteristics of each test will be reviewed, followed by comments on how the results are used in dam engineering.

Key Takeaways:
1. Understanding geotechnical index tests and what they tell us about soils.
2. Understanding laboratory density tests and how they are used in dam construction.
3. Understanding consolidation tests and how they are applied in settlement analyses.
4. Understanding permeability tests and how they are used in seepage analyses.
5. Understanding strength tests and how they are used in stability analyses.

Speakers: Amanda Hess, PE, GFT, Vice President, Geotechnical, Dams and Hydraulics

PDHs: This webinar is eligible for 2 PDH credits.

Understanding and Optimizing Riser and Outlet Structure Performance explores the role of riser and outlet structures in dam safety, reservoir operations, and regulatory compliance. This webinar examines the multiple purposes these structures serve—from normal releases and water supply to emergency drawdown—and the performance requirements they must meet under a range of operating conditions. Attendees will gain a practical understanding of the hydraulic controls governing riser and outlet behavior, including inlet, barrel, and outlet control, and how discharge is computed through these systems.

Building on these fundamentals, the webinar also acknowledges strategies to maximize the performance of both existing and proposed facilities. Topics include improving hydraulic efficiency through inlet modifications and evaluating the impacts of sliplining. The webinar will also address design considerations such as aeration and venting and terminal energy dissipation. 

Key Takeaways: 

1. What purposes do riser/outlet structures serve?

2. What requirements must riser/outlet structures meet?

3. What controls the hydraulics of riser/outlet structures?  How do you compute discharge through a riser/outlet structure?

4. How can you maximize existing and proposed facilities and ensure proper functioning

5. How can a riser structure design account for energy losses in the riser and outlet system and provide energy dissipation at the terminus?

Speakers: Henrik Forsling, PE, Civil/Structural Engineer; Amanda Clarke, PE, Geotechnical Engineer; Golsa Mahdavi, PhD, Structural Engineer; all AECOM

PDHs: This webinar is eligible for 2 PDH credits.

This webinar is intended for dam owners and operators, dam safety regulators, engineers, consultants, contractors, construction managers and inspectors, and other professionals involved in the analysis, design, construction, rehabilitation, inspection, and management of dams and hydraulic structures. The webinar will be relevant to both experienced practitioners interested in emerging technologies and those seeking practical ways to incorporate new tools and approaches into their day-to-day work and dam safety programs. 

Key Takeaways:
1. Identify emerging technologies and tools being applied to the analysis, design, construction, testing, and inspection of dams and hydraulic structures.2. Describe how digital tools and data-driven approaches, including digital twins and advanced modeling and visualization techniques, can support engineering evaluation, design, and construction.
3. Describe how AI and Machine Learning techniques can be used in anomaly detection and dam safety evaluation.
4. Recognize new and evolving construction technologies, such as intelligent compaction and automated data collection, and understand how they can improve construction quality, efficiency, consistency, documentation, and decision-making.
5. Evaluate emerging field testing and monitoring tools for assessing construction materials, placement conditions, concrete curing, and other construction quality parameters, including opportunities for more rapid or real-time feedback.
6. Discuss the practical benefits and limitations of adopting emerging technologies, including considerations related to accuracy, validation, cost, training, data management, regulatory requirements, and integration with established engineering practices.
7. Recognize opportunities to incorporate new technologies into day-to-day activities and broader dam safety and engineering programs while maintaining appropriate engineering judgment, quality control, and verification.

Speakers: Brad Kirksey, PE, Freese and Nichols, Inc., Principal / National Technical Specialist

PDHs: This webinar is eligible for 2 PDH credits.

Spillway selection is one of the most important decisions in dam planning, design, and rehabilitation. While a wide range of spillway types are available, some configurations are far more common than others. The reason is not that certain spillway types are universally superior, but that project constraints often make some alternatives more practical, constructible, and cost-effective than others. The engineer's challenge is not simply to select a spillway type, but to thoroughly investigate the site and project conditions to identify the spillway system most compatible with those constraints.

This webinar presents a practical framework for understanding how spillway alternatives are evaluated and screened based on site-specific conditions and project objectives. The discussion examines how hydrology, hydraulics, topography, geology, foundation erodibility, reservoir operations, constructability, flood routing during construction, and existing infrastructure influence the selection of spillway control structures, conveyance features, and energy dissipation systems. Special attention is given to the role of principal and auxiliary spillways and how they can be combined to manage both frequent and extreme flood events.

Using a decision-tree approach and real-world case studies, the webinar demonstrates how engineers progress from a broad range of potential alternatives toward a smaller set of viable spillway concepts. Attendees will gain an understanding of the spillway systems most commonly used in the United States, the site constraints that influence their applicability, and the practical considerations that often govern their selection. The presentation emphasizes that successful spillway selection is not simply a hydraulic exercise, but a multidisciplinary evaluation of technical, operational, constructability, and economic considerations.

Key Takeaways:
1. Identify the major spillway control structures, conveyance systems, and energy dissipation features commonly used at dams in the United States.

2. Recognize how topography, geology, foundation erodibility, hydrology, hydraulics, operations, and rehabilitation constraints influence spillway selection.
3. Understand the role of principal and auxiliary spillways and how they can be combined to manage both frequent and extreme flood events.
4. Develop a structured alternatives screening process using a decision-tree or alternatives matrix approach.
5. Evaluate constructability, flood routing during construction, operational requirements, and project economics as part of spillway system selection.

Speakers: Nathaniel Gee, PE 

PDHs: This webinar is eligible for 2 PDH credits.

This webinar explores a pivotal decade in U.S. water policy by tracing President Jimmy Carter’s lasting influence on dam safety and water resources. From early controversies like the Sprewell Bluff Dam to the national reckoning after the Teton Dam failure, we follow the momentum that led to Carter’s dam project review hit list, landmark congressional hearings, and the Presidential Memo that reshaped federal dam safety efforts. We also highlight key events and legislation, including major dam failures, the FEMA dam safety office, and the development of national guidelines. Join us as we commemorate 50 years of progress and examine how decisions from the 1970s continue to guide today’s dam safety programs.

Key Takeaways:
1. Recognize the long‑term impacts of 1970s dam safety initiatives on today’s federal, state, and local dam safety programs.

2. Understand how the policy shifts of the 1970s shaped the modern regulatory and interagency framework that dam safety engineers work within, helping participants navigate today’s requirements with clearer context.
3. Recognize how past failures and investigations established the foundations of current risk assessment practices, allowing engineers to better appreciate why certain standards and methodologies exist.
4. Identify lessons from Carter‑era coordination between federal agencies to improve today’s collaboration across local, state, and federal partners.

This product is recommended for those responsible for day-to-day oversight of dam operations and maintenance, HOA maintenance person or company, and county/city staff responsible for dam maintenance.
This training includes parts of introductory topics from some of ASDSO’s previously recorded technical webinars. Participants will view videos and take a short quiz on each topic. If the user completes each section and passes the quiz for each topic a certificate of completion is available. 

Topics include:

• History of Dam Safety Governance in the US
• Introduction to Embankment Dams
• Intro to Gravity Dams
• Introduction to Inspecting Dams for Owners and Operators
• Developing Operations and Maintenance Manuals for Dams
• Responding to Dam Emergencies
• Human Factors in the Edenville Dam Failure

There are no Professional Development Hours for this product.  

Speakers: Paul Schweiger, Gannett Fleming Inc. and Greg Richards, Gannett Fleming, Inc.

PDHs: This webinar is eligible for 2 PDH credits. 

Many dam failures have been averted by dam owners and engineers taking quick and effective action to intervene and stop an active dam failure from progressing. The focus of this webinar is to present the most common failure modes at dams and provide information on actions that can be taken to prevent or delay each failure mode. Case studies will be used to show examples of successful interventions. Actions that could potentially do harm and make conditions worse will also be discussed. The seminar will conclude with an overview of the new “Dam Intervention Toolbox” and how this interactive resource can be used as a companion to an Emergency Action Plan to help dam owners be better prepared to respond to a dam emergency.

Five Learning Objectives of This Course:

• Understand the most common failure modes at dams.

• Know what emergency measures can be taken to stop common failure modes at dams.

• Be aware of actions that can potentially make conditions worse.

• How to become prepared to respond to a dam emergency.

• Learn about the new “Dam Intervention Toolbox.”

• 1. Introduction:
  • a. Why This Topic Is Important
    • i. Share statistics on recent dam failures and consequences
    • ii. Being prepared to intervene to stop or delay an active dam failure is often overlooked and not included or elaborated upon in many EAPs.  Response time is limited and being prepared is the key to success.
    • iii. Benefits of an effective intervention (Prevent failure, provide more time to warn and evacuate, reduce consequences)
    • iv. Consequences of a harmful intervention 
  • b. What You Will Learn
    • i. Most common dam failure modes
    • ii. Actions that can be taken to prevent or delay each failure mode
    • iii. Actions that should not be taken, or that should be taken with caution – do no harm!
    • iv. Examples from case studies of responses (successful and unsuccessful) to actual dam emergencies
    • v. Know where to find the best resources
• 2. Most Common Dam Failure Modes
  • a. What Is A Dam Failure Mode?
  • b. Most Common Dam Failure Modes and Early Warning Signs
    • i. Seepage and internal erosion (piping, ….)
    • ii. Spillway Erosion
    • iii. Dam Overtopping
    • iv. Structural instability (slope instability, sliding, overturning, settlement)
    • v. Other
• 3. Intervention
  • a. Intervention Action Common to All Dam Failure Modes – Lower the Reservoir!
    • i. First, do no harm by making releases
      • 1. Loss of resource consequences
      • 2. Potential downstream consequences
      • 3. Potential structural consequences
      • 4. Potential loss of outlet control
    • ii. What to do if you do not have operable outlet works
      • 1. Siphons
      • 2. Controlled breach
      • 3. Lower downstream reservoir to contain or absorb breach flows (special case)
  • b. Seepage and Internal Erosion
    • i. Plugging leak from upstream side
    • ii. Reducing hydraulic gradient from downstream side
    • iii. Intercepting and filtering seepage
  • c. Spillway Erosion
    • i. Divert flows away from eroding area(s)
    • ii. Armor eroding areas
    • iii. Stopping or limiting erosive flow
  • d. Dam Overtopping
    • i. Lower reservoir in advance of pending flood
    • ii. Raise dam
    • iii. Armor dam
    • iv. Construct auxiliary spillway
• 4. What About Being Prepared to Respond to Public Safety Incidents?
• 5. Available Resources
  • a. Dam Owner Emergency Intervention Toolbox
  • b. ASDSO/FEMA Lessons Learned from Dam Incidents and Failure Website

Speaker: Irfan A. Alvi, P.E.

PDHs: This webinar is eligible for 2 PDH credits. 

Dam engineering involves dams, but is done by and for people. As a result, in order to achieve dam benefits while maintaining dam safety, we need to understand not just dams, but also the people involved in designing, constructing, operating, maintaining, and benefiting from them. Social scientists have been studying people scientifically for more than a century, and we are now at a point historically where the social sciences have generated valuable insights into human thought and behavior.

The aim of this webinar is to describe key socio-psychological insights and apply them to the practice of dam engineering, with an emphasis on judgment and decision-making. We will find that judgment and decision-making are influenced by aspects such as subconscious and conscious cognition, perception, belief, memory, self-concept, use of heuristics, cognitive and motivational biases, emotions, and group dynamics, and expertise, all of which contribute to both human capability and human fallibility.
This webinar will explore all of these aspects, will include extensive audience participation,  and will provide evidence-based suggestions for how we can improve our judgment and decision-making at both individual and group levels. The insights and suggestions presented in this webinar will be linked with the instructor's prior work on human factors to provide an overall framework for dam risk management. 

Four Learning Objectives of This Course:

• Understand the physical, social, and evolutionary context in which dam engineers operate
• Learn about the two main ways in which people “think”
• Learn about the socio-psychological factors which contribute to human fallibility and limitations, as well as human capabilities
• Learn ways to improve judgment, decision-making, and risk management in dam engineering

• Judgment and decision-making research
• Factors influencing judgement & decision-making
  o The human situation
  o Two kinds of thinking
  o Heuristics
  o Cognitive biases & expertise
  o Perception & belief
  o Memory
  o Emotions
  o Groups
  o Creativity
• Judgment
• Decision-making
• Risk management

Speakers: William R. Fiedler and Wayne King

PDHs: This webinar is eligible for 2 PDH credits. 

This webinar will involve the presentation of the Delhi Dam failure case history. Delhi Dam failed on July 24, 2010 during a record storm. The failure was a result of a number of factors all contributing to the ultimate failure. The review of dam failure by a forensic team allowed for a good understanding of the mechanisms that led to failure. Analyses were performed, which provided valuable insights into the weight of the contributions from the key factors. This webinar will describe in detail the history of Delhi Dam prior to the failure, a chronology of events leading to dam failure, studies and analysis performed as part of the forensic team efforts, and the findings and recommendations from the forensic team report.

Five Learning Objectives of This Webinar:

• Compounding mechanisms can increase the chance of a dam failing.
• Loadings that have never been experienced before at a dam can reveal deficiencies.
• Deferred maintenance on key features can contribute to dam failure.
• Early warning can prevent, or at least reduce, life loss from dam failure.
• In-depth evaluations of dam failures can provide valuable insights into case histories.

1. Dam Failure Event
2. Delhi Dam Background
3. Independent Panel of Engineers
4. Timeline of Failure
5. Geotechnical Considerations
6. Hydrology and Hydraulic Considerations
7. Emergency Response
8. Overall Findings
9. Status of Delhi Dam Today