Backed by years of experience, we routinely conduct design evaluations and hydraulic model studies for a variety of pump stations and intakes. Early in the design process, our engineers can collaborate with you to complete a detailed review of station design and offer recommendations to improve system hydraulics. Likewise, we can conduct a physical hydraulic model study to evaluate approach flow patterns, identify vortices, and measure swirling flow within the pump to satisfy requirements laid out by the Hydraulic Institute Standards for Pump Intake Design ANSI/HI 9.8-2018 and Pump Piping ANSI/HI 9.6.6-2022. Physical hydraulic modeling is the only currently accepted method to demonstrate compliance with the HI acceptance criteria.

Did you know?

Alden’s staff members have been involved with the development of Hydraulic Institute pump intake and pump piping standards since their inception.

Our experience with physical modeling of pump stations is reinforced by considerable research by our staff in the area of vortex formation and suppression, and scale effects on vortices in Froude models. Papers on scale effects on vortex flows and other topics related to intakes are regularly presented at national and international meetings, and are routinely featured in professional and industry publications. In addition, members of our staff have also written various chapters for handbooks and manuals on pump intakes and swirling flow.

Our knowledge related to Hydraulic Institute acceptance criteria is boosted by Alden’s Director of Hydraulic Modeling, Andy Johansson. Mr. Johansson currently serves as the Chair of the Hydraulic Institute Standards ANSI/HI 9.8-2018 Intake Design Committee and actively participates in the Hydraulic Institute Standards 9.6.6-2022 Pump Piping Standards Committee.

No matter if its fresh water intakes, flood control pumping stations, sewerage pumping plants, cooling water intakes, reactor containment sumps, pumped storage intake structures, or other pump intakes—Alden is your partner in ensuring a successful pump station design.

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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