Dam Safety with 3D Weirs: On-Demand

You must log in to register

Inadequate spillway capacity, significant hydrologic loadings on embankments and structures, and operation and maintenance are common dam safety issues, instigating the need for risk-reduction measures and/or rehabilitation. 3D weirs, or weirs with a crest length greater than the spillway width, are a particularly efficient approach to reduce these concerns. These weirs are also commonly used in new dams and may be useful as levee spillways. In some cases, these structures may be an alternative to gated spillways, which require operation and maintenance and can cause downstream flooding from misoperation or failure. Examples of 3D weirs include: arced or curved weirs, box-inlet drop spillways, labyrinth and piano-key weirs, and labyrinth fuse gates. Because of their hydraulic performance and site-adaptive geometries, these types of weirs are of increasing interest to those involved in dam safety, including practitioners, researchers, regulators, and dam owners. However, these spillways have complex hydraulic behaviors and can be challenging to develop efficient designs.

Brian Crookston, Ph.D., P.E.

Schnabel Engineering/Senior Engineer

Brian Crookston, PhD, PE is a Senior Engineer and Water Resources Technical Discipline Coordinator with Schnabel. His primary role is as an H&H technical resource for dam and levee projects company-wide. He has particular interests in water conveyance, hydraulic structures, and dam safety, including spillway hydraulics, flow acoustics, debris, energy dissipation, physical and numerical modeling, and design optimization.

Greg Paxson, P.E.

Principal, Schnabel

Schnabel Engineering, LLC.

Greg has over 25 years of experience with dam safety projects, ranging from inspections and evaluations to design and construction of dam safety modifications. This includes spillway upgrades, stabilization of gravity dams, and seepage remediation projects for embankment dams. He serves as chair of the Technical Journal Committee for ASDSO and chair of the USSD Hydraulics and Hydrology Committee. He also led an ASDSO Task Force charge with evaluating the design review process for dam safety projects, which included co-facilitating several soapbox and town hall sessions at ASDSO national conferences.
Greg has undergraduate and graduate degrees in civil engineering from University of Delaware and Villanova University, respectively.