Dams, Weirs & Hydropower Systems

• Design of dams, barrages, weirs, and hdropower structures
• Modeling of various aspects of dam hydraulics and sedimentation
• Physical and numerical modeling of hydraulic structures
• Water distribution system design
• Hydraulics of dam failures and changes in channel morphology due to dam failures
• Experimental and numerical modeling of scour and hydraulics at hydraulic structures

    Bisri Dam, Lebanon.

Responsible for planning, conceptual drawings, design criteria, designs, detailed drawings and specifications for all hydro-mechanical equipment including outlet hollow cone valves, top seal radial gates and fixed wheel emergency gates, intake trash racks.

    Godavari Barrage, India

Responsible for designs, specifications, and procurement for automation and state-of-the-art telemetry equipment for the world’s longest barrage with 186 barrage gates 20 m x 15 m size on Godavari Barrage for flood control and irrigation.

    Manganti Diversion Dam, Indonesia

For the existing Manganti diversion dam, investigated the problems of heavy leakage and severe vibrations of spillway radial gates. Developed designs for modifications to the sealing design and bottom shape of the gates which successfully eliminated the vibrations and leakage problems.

    Penjengkolan Irrigation Diversion Weir, Indonesia

Design responsibility for canal headworks gates.  Designed the installation, specified the gate equipment, approved manufacturer’s drawings, and conducted the factory and field inspections.

    Pranburi Dam, Thailand

Responsible for detailed designs, drawings and specifications for radial type spillway gates with electric rope drawn hoists for Royal Irrigation Department in Thailand.

    Recreta Dam Project, Peru

Hydraulics/ hydro-mechanical design for Recreta Dam and Irrigation Project.  Prepared hydraulic designs, drawings, technical specifications, and cost estimates for the irrigation outlets and intakes including gates and appurtenances.

    Valenciano Dam, Puerto Rico

Design of the Valenciano Dam in Puerto Rico in cooperation with CSA Group.  Hydraulic design of the Valenciano Dam, its spillway, and all appurtenances and the SCADA system for four crest gates each about 47′ wide x 17′ high.  Valenciano is a 100-foot high roller compacted concrete (RCC) water supply dam with a converging spillway and converging stilling basin design. We designed the converging spillway and converging stilling basin (unique feature), the spillway profiles, the stilling basin, the downstream channel training wall heights as well as conducting hydraulic laboratory testing of the dam. Conducted reservoir sedimentation studies for service life computations as well as developing sediment mitigation measures including structural and operational measures.

    Sanmen Xia Dam Reservoir, Yellow River China

In this World Bank funded study, worked with Chinese engineers from the Yellow River Commission to model reservoir sedimentation taking place in Sanmen Xia Dam.  Sanmen Xia Reservoir is located in the lower part of the Middle Yellow River in China.  It is a multi-purpose hydro-project mainly used for flood control. The drainage area above the dam amounts to 688,000 km2.  The Yellow River cuts through an extensive loess plateau where a large portion of it suffers from severe soil erosion.  The channel flows carry up to 60 percent solids by weight consisting of mainly fine sands and silts.  Due to the large quantities of sediment carried by the Yellow River, Sanmen Xia Reservoir was filled within several years after its completion. In this World Bank project, numerical modeling of a 150 km segment of the Yellow River upstream from the Sanmen Xia Reservoir was accomplished by using the GSTARS model developed for the US Bureau of Reclamation by Dr. A. Molinas, Hydrau-Tech, Inc.  The GSTARS model for the Yellow River has been successfully used to simulate the typical reservoir operations; reservoir operation rules were refined to optimally pass the incoming sediments with minimal retention in the reservoir.

    Lock and Dam No. 26 (Replacement) Project, Saint Louis, Missouri, USA

Lock and Dam No. 26 is located on the Mississippi River near Saint Louis, Missouri.  Due to increased demand on the aging system, the U.S. Army Corps of Engineers has replaced the old lock and dam with a new structure.  The construction of the new Lock and Dam No. 26 was accomplished in 3 phases.  In Phase 1, a cofferdam was built on the right bank of the Mississippi River that constricted the flows by 52 percent.  In Phase 2, part of this cofferdam was removed, and with new additions, it was moved to the middle of Mississippi River resulting in 44 percent constriction.  During the Phase 1 construction, due to severe contraction the river segment along the cofferdam scoured up to 35 feet.  Of this amount, 15 feet of it occurred in a single flooding event that was estimated as the 10-year flood. In order to assess the additional scour that could occur during the rest of the Phase 1 and during the Phase 2 construction, a numerical modeling study was conducted.  The GSTARS (Generalized Streamtube Model for Alluvial River Simulation) model developed by Dr. Molinas, President, Hydrau-Tech, Inc. was applied to study scouring patterns around the new Lock & Dam 26 site. The GSTARS model divides the flow channel into conceptual stream tubes. Hydraulic conditions and sediment transport is computed along each tube separately. During Phase 1, maximum velocities and consequently maximum scour occurred at the nose region of the cofferdam.  GSTARS simulated the scour at the nose region and along the cofferdam very closely.  Following the verification runs, potential for additional scour for Phase 1 and Phase 2 cofferdam configurations were investigated. It was determined that additional scour was expected and structural and pumping requirement changes were made to reflect computations.

    Rock Creek and Cresta Dam Sedimentation and Design of Mitigation Structures, California, USA

Rock Creek and Cresta dams are two of the concrete gravity dams owned and operated by Pacific Gas and Electric Company along the North Fork Feather River, California.  Since their construction in 1950, sediments have accumulated in the Rock Creek and Cresta reservoirs resulting in potentially reduced reliability of dam and powerhouse operations.  In order to mitigate the sedimentation problems within the environmental concerns, the structural modification initially proposed for Rock Creek dam consisted of constructing a 30 ft wide by 30 ft high top-sealing radial gate through the right abutment.  For Cresta dam, two new 10 ft diameter outlet pipes were proposed through the dam. A laboratory model study to test effectiveness of the proposed modifications was conducted by Dr. Albert Molinas.  Scaled down models of the dams were placed in undistorted moveable-bed river models.  Using series of experiments using lightweight plastic pellets and very fine sand to simulate reservoir sediments, the location of the proposed structures, their dimensions, and operational efficiencies were optimized.  The vertical positioning of both the sediment pass through pipes at the Cresta Dam and the 30 ft by 30 ft rectangular radial gate in the Rock Creek Dam were crucial to the sediment passing efficiencies of these structures.  For the Rock Creek Dam, water discharged through the submerged sediment pass-through spillway posed an additional challenge by creating a recirculation zone immediately downstream from the dam.  This adverse effect was resolved by experimentally adjusting the discharge distribution between the pass-through and main spillway gates, and by developing spillway operation rules.

    Bachman Dam Renovation Project, Texas, USA

Bachman Dam was built in Dallas, Texas, around the turn of the century.  The dam has a converging spillway that has deteriorated through time.  Recent flooding events demonstrated that the safety of the spillway and consequently the dam is at danger.  In this study, Hydrau-Tech, Inc. assisted Kellogg, Brown and Root (KBR, formerly Halliburton) in conducting hydraulic and hydrologic computations, PMF computations, verifying compliance with FERC, FEMA, and Texas Environmental Water Quality regulations, as well as assisting in selecting appropriate dam and spillway design options.

    Sedimentation Study at St. Charles Casino Cofferdam, Missouri River, Saint Louis, USA

St. Charles Station Casino is located on Missouri River near Saint Louis, Missouri at approximately 5 miles upstream from its confluence with the Mississippi River.  Riverboats and barges forming the casino structures (flotilla) are located in the wake region of a temporary cofferdam structure, immediately downstream from the Missouri State Highway 70 Bridge.  This 400 ft wide by 800 ft long cofferdam contains extensive resort facilities that are being constructed.  Due to excessive sediment accumulation behind the cofferdam, according to governing laws, the SCSC faces closure if the flotilla loses its floating status.  In order to avoid the high sediment inflow into the flotilla region, a structural solution is proposed to build an 800 ft long sheet-piling diversion wall to enclose the flotilla.  It is hoped that this wall would deflect the oncoming sediments away from the casino area and avoid sediment built-up. The effectiveness and the feasibility of the proposed diversion wall and the identification of stagnation flow regions to improve efficiency of the design were determined by using a state-of-the-art finite element surface flow model (FEM) developed by Hydrau-Tech (Molinas and Hafez, 2000).

    Carraizo Dam, Puerto Rico, USA

Designed gates and the SCADA system for eight radial gates, each about 41′ wide and 36′ high, and prepared recommendations for the rehabilitation of the gates.  Carraizo is a 100-foot high concrete gravity dam which overtopped during Hurricane Hugo in 1989.  The overflow designs developed for the dam eliminated the need for bascule gates on the tainter gates and saved significant costs.