We address problems related to civil engineering hydraulics with a combination of scaled physical modeling and testing and computational fluid dynamic (CFD) modeling. Modeling provides a cost effective means to evaluate the performance of structures and devices before they are constructed, whether they are for new facilities or the improvement and retrofit of existing ones.

We can execute multiple projects at any given time while maintaining cost and schedule requirements. Our engineering experts study and optimize designs for projects such as intake and discharge structures, culverts, flood walls and flood protection, dams, spillways, coastal flooding, sedimentation, erosion, canals and river mechanics.

"They'd be the only people I'd consider. You don't mess around with something that works. We have established such a good working relationship. I know that if there was a problem, I could pick up the phone and get it resolved quickly."

Edmond Pepper

Vice President, Pepper & Associates

The best first step for choosing your modeling approach is a conversation.

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The Cedar Cliff dam and hydropower project is located approximately six miles from Cullowhee, in Jackson Country, North Carolina. The dam and hydroelectric facility is owned by Duke Energy and is located downstream of three other hydroelectric projects that are operated as a system.

The primary spillway includes a Tainter gate and the existing auxiliary spillway system includes two fuse plug sections (with different crest/activation elevations).  It was determined that the combination of the primary and auxiliary spillway systems were not adequate to safely pass the regulatory-increased Inflow Design Flood (IDF). The construction of a Hydroplus Fusegate system with six semi-labyrinth Fusegates in an enlarged auxiliary spillway channel was selected to increase spillway capacity to safely pass the new IDF which is now the full Probable Maximum Flood (PMF). 

Two reduced scale physical models were constructed to determine the required size of a ventilation system for the proposed Cedar Cliff Fusegates and headpond and tailwater levels at each Fusegate for flows up to the sixth Fusegate activating. The tailwater levels were required for design of the Fusegate ballast system.  

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Model testing looking upstream
Civil Infrastructure | Hydrology Hydraulics and Fluids
Cedar Cliff Spillway

Physical model study to determine hydraulic performance of a proposed auxiliary spillway system during flooding events