Dams and Water Resources

Dams and Water Resources

RIZZO has always had a particular dedication to dams and water resources projects.

We have continued to build upon this history through our work with regulatory agencies and environmental groups in both public and private sectors around the world.  Our projects range from small spillway design and construction to large dam rehabilitations, complete rebuilds, hydroelectric feasibility studies, and project development.

RIZZO has experience with many types of dams, including conventional concrete, Roller Compacted Concrete (RCC), earthfill, rockfill, masonry concrete gravity, arch, buttress, and timber crib dams. In particular, RIZZO has extensive experience in the following areas:

  • Conceptual to final design on all types of dams
  • Analysis and design for dam evaluation and rehabilitation
  • Dam Safety Evaluations and Inspections
  • Embankment dams and their behavior, including seismic performance
  • RCC dam design, including mix designs
  • Investigation of all types of dam soils and foundations
  • Hydrology and Hydraulic studies
  • Subsurface/Geotechnical Investigations
  • Geological studies
  • Foundation improvement design, including grouting and cutoff walls
  • Seismic hazard analysis
  • Seismic analysis and design
  • Dewatering system design

Additional details for our experience with different types of dams are provided below. For a summary of our key dams and water resources projects, click here.


I. Conventional Concrete and RCC Dams

RIZZO provides engineering services for new and existing conventional concrete and RCC dams. Existing dams may not meet current design criteria, and remedial measures or rehabilitation are sometimes required. RIZZO has experience with remedial designs for existing dams, including the installation of post-tensioned anchors and spillway modifications.

RCC is commonly used in the construction of new dams. The primary advantage of RCC over conventional concrete is its low cost and speed of construction. Our staff has years of experience with all aspects of RCC, including the production and placement of both lean and high paste RCC. RIZZO has performed mix design and QA and QC services for several projects, including lab testing, monitoring of RCC placement, mixing, and conveying. We have participated in two of the largest recent dam remediations in the United States using RCC: the Taum Sauk Upper Reservoir Rebuild and the Saluda Dam Remediation.


II. Earth Embankment Dams

Embankment dams are classified as either earthfill or rockfill depending on the materials used for construction. Our staff has over 30 years of experience in the analysis, design, and construction of earthfill and rockfill dams. RIZZO routinely performs static and dynamic slope stability analyses for embankment dams, and we also have experience performing seepage and slope stability analyses for large excavations located adjacent to dams and other hydraulic structures. RIZZO performs two-dimensional static and dynamic finite element analyses, and dynamic stability analyses for earth embankment dams typically include performing seismic risk analyses; liquefaction potential studies; and deformation analyses. RIZZO staff has the capabilities to perform all of these services in-house without support from external consultants or subcontractors.

RIZZO has experience designing and managing projects to address inadequate spillway capacity at small to medium sized dams. Through incremental dam break analyses, cost effective solutions such as RCC for overtopping protection, innovative construction materials such as grouted riprap, and other measures we are able to develop creative, cost effective solutions for our clients.


III. Hydroelectric Facilities

RIZZO has extensive experience in the Hydroelectric Industry, and senior members of our staff have been involved in the industry for over 45 years. RIZZO’s experience includes: the evaluation of powerhouse structures, gates and valves; penstocks; hydroelectric equipment and controls; performing feasibility studies for new facilities; licensing and permitting; construction management; operation; the development of remedial measures; and upgrades for the repowering of existing facilities.

RIZZO has two current staff members (Hans Hasnay and Bill Broderick) with over 20 years of experience in the electric utility industry. These individuals possess an owner’s perspective that is unique to consulting firms serving the dam industry.

RIZZO personnel are involved extensively with projects licensed by the FERC, and we perform Part 12 Inspections, PFMAs, Dam Safety Surveillance and Monitoring Plans and Reports, and analysis and design for FERC licensed facilities. Our long term relationships with utilities demonstrates their confidence in the quality of our work, and the fact that these clients continue to return to our firm for additional work when the consulting services market is saturated is evidence of the quality of our work.