Engineering Commons^™

Repair Of Failing Spirit Lake Outlet Tunnel At Mount St. Helens, J. P. Britton, S. K. Askelson, C. M. Budai, D. H. Scofield

International Symposium on Hydraulic Structures

The 18 May 1980 eruption of Mount St. Helens resulted in one of the largest debris avalanches recorded in history. The debris avalanche blocked the natural outlet of Spirit Lake. To prevent an uncontrolled and catastrophic lake break-out, the U.S. Army Corps of Engineers (USACE) constructed the Spirit Lake Outlet Tunnel from 1984 to 1985. Because Spirit Lake is located in the Mount St. Helens National Volcanic Monument, the project was transferred to the U.S. Forest Service (USFS) for ownership and management. During original tunnel construction, the most difficulty occurred within the 90-m-wide Julie and Kathy L. shear zone complex. …

Optimization Of Air Entrained Grout Enriched Roller Compacted Concrete For Improving Freeze-Thaw Resistance Of Hydraulic Structures, E. S. Musselman, R. J. Flynn, G. J. Zimmer, J. R. Young Pe

International Symposium on Hydraulic Structures

Roller compacted concrete (RCC) is frequently used to construct gravity dams, stepped spillways, and to armor earthen embankments for passing extreme floods. Early experience on RCC dam applications in the 1980s showed a tendency for seepage to develop along the lift lines. Therefore, RCC dam designers started including an upstream facing system as a watertight barrier. An alternative facing material that has been used extensively overseas and is starting to gain more widespread acceptance in the United States is Grout Enriched RCC (GERCC). The grout enriched method of face construction has been shown to be less expensive than other facing …

South Channel Dam Rehabilitation Project - Successfully Addressing Dam Rehabilitation Challenges, M. D. Graeser, M. C. Jensen

International Symposium on Hydraulic Structures

The Post Falls South Channel Dam is located on the Spokane River in Post Falls, Idaho. The concrete gravity dam was constructed in 1906 and was recently rehabilitated. The rehabilitation project included several design elements; the primary objectives were the replacement of the six spillway gates and hoists and significant rehabilitation of the concrete. The South Channel Dam rehabilitation encountered several challenges due to the age and condition of the existing structure, the large scale of the rehabilitation, and the location of the project. The concrete rehabilitation addressed several challenges which are presented in detail. The existing concrete consisted of …

Fish Passage Behavior Behavior Through Baffled And Nonbaffled Culvert, M. A. Khodier, Blake P. Tullis

International Symposium on Hydraulic Structures

Culverts can have a negative impact on fish passage. Installing baffles inside culverts can potentially improve culvert fish passage by decreasing the flow velocity and increasing the flow depth. Fish passage behaviors of wild brown trout through a small prototype-scale (0.6 m diameter), 18.3 m in length, baffled, and non-baffled culverts were observed in the laboratory for a variety of discharges and pipe slopes (up to 6%). The baffle height and spacing was 0.15 and 0.9 times the culvert diameter, respectively. The correlation between successful fish passage, sample fish population, and the fish length was evaluated. The influence of baffles …

Technical Developments In Fish Exclusion, Guidance, And Collection Materials, A. L. Peters

International Symposium on Hydraulic Structures

Construction of mills, dams and other structures in rivers and streams, and the withdrawal of water for irrigation or cooling industrial facilities vital to social and economic progress, have impacted the survival of marine life. Barriers and guidance or collection nets can protect fish and aquatic species while allowing water to flow unimpeded for commercial and industrial use. However, nets can attract aquatic growth, fill with debris, degrade with environmental stress, and be expensive to operate and maintain.

A closer look at the technical developments of materials and net designs in diverse settings can offer guidance that will be of …

Evaluation Of Flexible Barrier And Sabo Dam To Control Effects Of Debris Flow In Santo Domingo Ravine, J. W. Cabrera Cabrera, L. F. Castillo Navarro

International Symposium on Hydraulic Structures

Coast of Peru is characterized for the presence of ephemeral creeks which drain water only on wet season. The extremely dry soil and pebble combined with precipitation produce debris flow in a seasonal geodynamic. This is the case of Santo Domingo ravine which is located at eastern Lima, and drains their water to Rimac River. In this article the vulnerability of villages near to Santo Domingo ravine by debris flow and use of flexible barrier and sabo dams are analyzed. In a first stage, the liquid hydrograph to a 100 years return period was built and a solid hydrograph, a …

St. Mary Diversion Dam – Case Study Of A 100 Year Old Diversion, B. J. Heiner, J. Wagner

International Symposium on Hydraulic Structures

After 100 years of service, the St. Mary Diversion Dam is being replaced with a new design that will provide more effective fish passage and protection. The diversion is located in northern Montana, adjacent to the east side of Glacier National Park. It diverts water from the St. Mary River 1.21 km (0.75 mile) downstream of Lower St. Mary Lake. The existing 60.35-meter-long and 1.83-meter-high (198-foot-long and 6-foot-high) concrete weir diverts up to 24 cubic meters per second (850 cubic feet per second) design flow from the St. Mary River into the North Fork of the Milk River through a …

The Role Of Physical And Numerical Modeling In Design Development Of The Priest Rapids Fish Bypass, T. C. Lyons, M. Politano, C. Dotson, L. J. Weber, D. Hay

International Symposium on Hydraulic Structures

This paper describes a number of years of physical and numerical modelling that were instrumental in the development of the final fish bypass design at Priest Rapids Dam. Three physical models and multiple numerical models were used to guide the design of the fish bypass including its location on the dam, impact on forebay and tailrace flow patterns, intake configuration, design flow rates, flow control scheme, tailrace egress, potential for scour near the dam, potential impacts on total dissolved gas (TDG), impacts on spillway and powerhouse operation, and overall fish friendliness of the bypass.

Throughout those years of design work, …

Study On The Proceeding Of Hydraulic Problem Of Simulating Natural Fish Passage, Zhijuan Wang, Qingyuan Yang, Minghai Huang, Yong He

International Symposium on Hydraulic Structures

Fish passage in water conservancy projects is an important means of improving river connectivity, and reducing the impact on the ecological environment. Simulating natural fish passage, which aims at the purpose of the river ecological corridor by the means of ecological optimization on the structure and section type based on the traditional fish passage, is promoted and applied in recent years gradually. At the same time, the hydraulic research related to the simulating natural fish passage has made great progress. In this paper, we firstly collected and summarized the research experience of the domestic and foreign typical fish passage, analyzed …

Application Of The Optical Flow Method To Velocity Determination In Hydraulic Structure Models, D. B. Bung, Daniel Valero

International Symposium on Hydraulic Structures

Optical flow estimation is used in Computer Vision for detection of moving obstacles in a sequence of images. The optical flow (OF) is defined as the displacement of brightness patterns between two sequent images. In this paper,this method is applied to high-speed images taken in hydraulic structure models for determination of velocity fields.Water is seeded with tracer particles in two cases and is self-aerated in a third case. It will be shown that the OF method gives valuable results which compare well to other velocity measurements, e.g. by Particle ImageVelocimetry. The OF method is generally more time-consuming compared to PIV, …

Optimizing A New Flow Diversion Structure For The Planned Expanding Of The Spillway For The Malter Dam In Germany Using A Physical Hydraulic Model, J. Schmidt, J. Wieland, J. Jensen

International Symposium on Hydraulic Structures

The State Reservoir Administration of Saxony is planning to expand the spillway discharge capacity of the 102-year-old Malter Dam. After a catastrophic flood in 2002, updated hydrologic modeling indicated that the design discharges for the dam had increased significantly. As a result, the original spillway discharge capacity was insufficient to pass the revised design flows. A design concept was developed to add a second spillway and stilling basin to the dam, and to pass flow into this spillway using a novel vertical flow separator. The design and performance of this system was evaluated using a 1:25-scale physical model. The modeling …

Evaluation Of Spillway Stilling Basin Performance And Reservoir Sediment Flushing In A Physical Model Case Study: Due Hydroelectric Project In Ecuador, Ali Habibzadeh, Brian Hughes, Hernan Barahona

International Symposium on Hydraulic Structures

The Due Hydroelectric Project is a proposed 50 MW run-of-river hydroelectric project being developed by Hidroalto SA. The project will be located on the Rio Due in Ecuador. The civil works of the intake facility will be comprised of a 133.45 m wide diversion weir, with two overflow spillways and six gated sluice channels; a four bay intake structure with sediment excluder; and, a fish bypass facility. Northwest Hydraulic Consultants (NHC) evaluated the initial design of the Due intake and spillway facilities using a 1:35 Froude-scaled physical model for river discharges ranging from the intake design discharge of 57.2 m3 …

Impacts Of Tailwater On The Design Of Several Stilling Basins In The Usa, L. E. Shearin-Feimster

International Symposium on Hydraulic Structures

The dissipation of excess energy from flows exiting a spillway is often needed to prevent or reduce to acceptable levels conceivable negative impacts to the downstream channel, spillway, and dam (e.g., erosion, undermining). The optimization of a hydraulic jump type stilling basin using general purpose published design methodologies (i.e., USBR, SAF, etc.) for a project can be challenging, as these methodologies may not account for all site specific conditions and structure formulations by designers. Also, it is not often clear to a designer as to which flow rates (and corresponding flood events) will have the greatest influence on the basin …

A Remotely Controlled Siphon System For Dynamic Water Storage Management, Arturo Leon, Ali Alnahit

International Symposium on Hydraulic Structures

Previous research has concluded that upland wetlands could be effective to control small floods, yet for large floods their value may be greatly reduced as their storage capacity may be exceeded. A potential solution could be to release water from wetlands ahead of (e.g., few days before) a heavy rainfall event that is forecasted to produce flooding. In this case, the wetlands would be partially empty when this rainfall occurs. This work is part of a long term project which aims at developing a decision support system (DSS) that will determine optimal flooding scenarios with dynamic management of wetlands using …

Predicting Velocity At Limit Of Deposition In Storm Channels Using Two Data Mining Techniques, H. Bonakdari, I. Ebtehaj

International Symposium on Hydraulic Structures

In storm channel system design, the system should have the ability to transfer the entire input flow to the system as well as prevent sediment settling. Existing methods of determining the velocity at limit of deposition are minimum velocity or regression-based equations. Because minimum velocity methods fail to consider the effective flow and sediment transfer parameters, while regression-based equations are not flexible in terms of various hydraulic conditions and they do not perform well. Thus, using such equations leads to a lack of designs with optimum, confident coefficients. In this study, Extreme Learning Machines (ELM) are employed to predict velocity …

Stepped Chute Training Wall Height Requirements, S. L. Hunt, K. C. Kadavy

International Symposium on Hydraulic Structures

Stepped chutes are commonly used for overtopping protection for embankment dams. Aerated flow is commonly associated with stepped chutes if the chute has sufficient length. The aeration and turbulence of the flow can create a significant amount of splash over the training wall if not appropriately accounted for in the design of the structure. According to the United States Department of Agriculture (USDA)-Natural Resources Conservation Service (NRCS) Technical Release 60 Earth Dams and Reservoirs, a structural spillway should be designed to pass the freeboard hydrograph such that it does not cause serious damage to the embankment or the structure itself. …

A Risk Based Framework For Evaluating Gated Spillway Operations, Greg Paxson, Marty Mccann Jr, Mark Landis

International Symposium on Hydraulic Structures

Gated spillways are often necessary to provide both operational flexibility and discharge capacity to pass large flood events. However, gated spillways present operational challenges to dam owners and operators, often necessitating development of a flood operations plan (FOP) that is used in tandem with the dam’s emergency action plan (EAP). Even a well-intentioned and robust FOP/EAP can require personnel to predict flooding, use judgment particular to the requirements of the plan, and react quickly. In addition, all of the equipment required to operate the gates need to function as designed and be operated in accordance with the FOP.

This paper …

Determining Optimal Discharge And Optimal Penstock Diameter In Water Turbines, Arturo S. Leon

International Symposium on Hydraulic Structures

Minimizing water consumption for producing hydropower is critical given that overuse of flows for energy production may result in a shortage of flows for other purposes such as irrigation and navigation. This paper presents a dimensional analysis for finding optimal flow discharge and optimal penstock diameter when designing impulse and reaction water turbines for hydropower systems. The objective of this analysis is to provide general insights for minimizing water consumption when producing hydropower. This analysis is based on the geometric and hydraulic characteristics of the penstock, the total hydraulic head and the desired power production. As part of this analysis, …

Turbulence And Energy Dissipation In The Developing Non-Aerated And The Fully-Developed Aerated Flows On A Stepped Spillway, G. Zhang, H. Chanson

International Symposium on Hydraulic Structures

Stepped spillways are characterised by highly turbulent air-water flows and a large rate of energy dissipation compared to smooth chutes. Herein detailed measurements were performed in both the developing non-aerated and fully-developed air-water flow regions on a large 1V:1H stepped spillway model. In the developing flow region, large total pressure fluctuations and turbulence intensities were recorded next to the pseudo-bottom. Downstream of the inception point, large total pressure fluctuations were recorded which were mainly induced by density fluctuations. The water turbulence intensities in the air-water flow region did not differ significantly from those in the developing flow region. The steps …

Unsteady-Flow Modeling For Emergency Shutdown Of The Cap Canal, Bert Clemmens, Brian Wahlin, Marcus Shapiro, Patrick Dent

International Symposium on Hydraulic Structures

The Central Arizona Project (CAP) is designed to bring about 1.9 ML of Colorado River water per year to Maricopa, Pima, and Pinal counties in Arizona. CAP carries water from the Colorado River at Lake Havasu toTucson. The CAP canal system is a 540 km long system of conveyance system aqueducts, tunnels, pumping plants,pipelines and a large reservoir (just north of Phoenix, AZ). Water is pumped uphill from the Colorado River. This study was conducted for the Hayden-Rhodes Aqueduct of the Central Arizona Project (CAP), which starts at the after bay of the Bouse Hill Pumping Plant and extends to …

Managing Dam Safety Risks Related To Hydraulic Structures, W. R. Fiedler

International Symposium on Hydraulic Structures

The Bureau of Reclamation’s Dam Safety Program manages risk for over 300 high and significant hazard dams.When risk estimates for potential failure modes indicate increasing justification to take action to reduce risk, dam safety recommendations are typically made. The dam safety recommendations can focus on collecting additional data/performing studies to better quantify risk or on initiating corrective actions to address well defined risks. Dam safety recommendations within Reclamation’s inventory address a number of different issues, such as those related to internal erosion, flood overtopping of dams and seismic stability of dams. Dam safety recommendations related to hydraulic structure potential failure …

Junction Chamber At Vortex Drop Shaft: Case Study Of Cossonay, G. Crispino, D. Dorthe, T. Fuchsmann, C. Gisonni, M. Pfister

International Symposium on Hydraulic Structures

The drainage network of the city of Cossonay (Switzerland) is currently being adapted for future needs. In particular, it is required to drain increased storm discharges due to a population augmentation, and to provide an adequate concept to overcome unfavorable geotechnical conditions.

Vortex drop shafts are sewer manholes commonly applied in steep urbanized topographies to connect conduits across large elevation differences. In Cossonay, the existing 48 m high vortex drop shaft, with a diameter of 1.5 m, allowed the storm discharge to flow from the city to a watercourse issued at half of the valley height. The discharge capacity was …

Experimental Study Of Head Loss Over Laser Scanned Rock Tunnel, L. R. Andersson, I. A.S. Larsson, J. G.I. Hellstrom, P. Andreasson, A. G. Andersson

International Symposium on Hydraulic Structures

Flow in hydropower tunnels is characterized by high Reynolds number and often very rough rock walls. Due to the roughness of the walls, the flow in the tunnel is highly disturbed, resulting in large fluctuations of velocity and pressure in both time and space. Erosion problems and even partial collapse of tunnel walls are in some cases believed to be caused by hydraulic jacking from large flow induced pressure fluctuations. The objective of this work is to investigate the effects of the rough walls on the pressure variations in time and space over the rock surfaces. Pressure measurement experiments were …

Numerical Investigation Of The Flow Field Inside A Manhole-Pipe Drainage System, Md Nazmul Azim Beg, Rita Carvalho, Pedro Lopes, Jorge Leandro, Nuno Melo

International Symposium on Hydraulic Structures

Urban drainage networks contain a large number of structures. Manhole is the most common and the most important as it connects pieces of sewer pipes to form sewer networks. Understanding the hydraulics of a manhole-pipe drainage system is either important as this may sometimes become the bottlenecks of the sewer systems. In this study, the flow structure and flow hydraulics of a specific manhole-pipe sewer system was analysed numerically in view of further research to investigate sediment/ suspended solid transport in the system. The numerical model was compared with discharge and water pressure/depth data from experimental model. Different discharges and …

Effects Of Hydraulic Jump Motion On Air Entrainment In Closed Conduits, J. D. Mortensen, J P. Kubitschek

International Symposium on Hydraulic Structures

Air vent systems are designed to protect hydropower penstocks and reservoir outlets under various operating conditions. During an emergency closure of an upstream gate the hydraulic jump that forms downstream of the gate is not stationary and may advance downstream potentially increasing the total air demand. A lab-scale physical model of a general outlet works piping configuration was constructed at Reclamation’s Hydraulics Laboratory in Denver, CO to observe hydraulic jump behavior during emergency gate closures. Parameters including gate discharge, gate closure rate, air vent size, and downstream pipe pressure were tested at two different pipe slopes. Results indicate that the …

Cabinet Gorge Dam Spillway Modifications For Tdg Abatement - Design Evolution And Field Performance, S. L. Dunlop, I. A. Willig, G. E. Paul

International Symposium on Hydraulic Structures

Avista is implementing spillway modifications to reduce TDG supersaturation downstream of Cabinet Gorge Dam.The key feature of the modifications is the addition of roughness elements, similar to supercavitating baffle blocks,to break up the spillway jet thereby reducing the depth of plunge and TDG supersaturation. The work is progressing in a step-wise manner. A single bay was modified in 2012 and field tested in 2013. Following the initial field tests, aCFD model was developed to aid in design refinements for the prototype and to improve the design prior to modification of subsequent spillway bays. The prototype demonstrated that spillway modifications are …

Free-Surface Aeration In A Steep Stepped Spillway, G. Zhang, H. Chanson

International Symposium on Hydraulic Structures

Self-aeration has important civil and environmental applications in stepped chutes, ranging from cavitation protection to enhanced air-water mass transfer. Air bubble entrainment occurs when the turbulent stresses in the boundary layer exceed the combined effects of surface tension and buoyancy. The governing equations for air diffusion in the rapidly-varied region next to, and in the gradually-varied region away from the inception point of aeration are introduced. New and existing solutions to these equations are discussed and compared with new experimental data. An analytical model for flow bulking is introduced. The concept of negative diffusivity is discussed.

Physical Modeling Of An Aerating Stepped Spillway, S. Erpicum, M. Lodomez, J. Savatier, P. Archambeau, B. J. Dewals, M. Pirotton

International Symposium on Hydraulic Structures

To mitigate the negative effects on the water quality in the downstream river of a projected large dam, and in particular to increase the dissolved oxygen concentration during low flow periods within the first 10 years of dam operation, an aerating weir has been designed and tested on a physical model at the Laboratory of Engineering Hydraulics (HECE) of the Liege University. The design of the structure has been done considering data from the literature. The selected solution is a 3 m high stepped spillway designed to operate in nappe flow conditions within the range of design discharges (25 – …

Decision-Making Through Sustainability, F. Pardo-Bosch, A. Aguado

International Symposium on Hydraulic Structures

From immemorial time, dams have contributed significantly for the progress of civilizations. For this reason, nowadays, there is a vast engineering heritage. Over the years, these infrastructures can present some ordinary maintenance issues associated with their normal operation or with ageing processes.

Normally, these problems do not represent an important risk for the structure, but they have to be attended. To do it, owners of dams have to finance many ordinary interventions. As it is impossible to carry out all of them at the same time, managers have to make a decision and select the most “important” ones. However, it …

Water System Operator Training For The Central Arizona Project, Brian Wahlin, Bert Clemmens

International Symposium on Hydraulic Structures

The Central Arizona Project (CAP) is designed to bring about 1.85 billion cubic meters (1.5 million acre-feet) of Colorado River water per year to Maricopa, Pima, and Pinal counties in Arizona. The CAP canal system is a 540-km (336-mile) long system of conveyance aqueducts, tunnels, pumping plants, and pipelines that is monitored and remotely controlled using Supervisory Control and Data Acquisition (SCADA) software from CAP headquarters in Phoenix, AZ. Because the CAP is crucial to the renewable water supply in Arizona, operating the canal effectively is of utmost importance. Typical day-to-day operations for Water System Operators on the CAP involve …