EENF Wheelwright Pond Dam Removal Project

Total Page:16

File Type:pdf, Size:1020Kb

EENF Wheelwright Pond Dam Removal Project Commonwealth of Massachusetts Executive Office of Energy and Environmental Affairs Massachusetts Environmental Policy Act (MEPA) Office Environmental Notification Form For Office Use Only EEA#: MEPA Analyst: The information requested on this form must be completed in order to submit a document electronically for review under the Massachusetts Environmental Policy Act, 301 CMR 11.00. Project Name: Wheelwright Pond Dam Removal Project Street Address: Mill Street (Hardwick) Municipality: Hardwick and New Braintree Watershed: Chicopee Universal Transverse Mercator Coordinates: Latitude: 42.352418 Zone 18T E 735805.26, N 4692876.78 Longitude: -72.136976 Estimated commencement date: Aug. 2022 Estimated completion date: June 2026 Project Type: Dam Removal Status of project design: Dam Removal 95%complete MassCentral Rail Trail Bridge: 25% Complete RJ McDonald Mitigation: 75% Complete Proponent: Raitto Industrial Park, Inc. Street Address: 36 Mill Street Municipality: Wheelwright State: MA Zip Code: 01094 Name of Contact Person: Kristin Dippold Firm/Agency: Tighe & Bond, Inc. Street Address: 1 University Ave Municipality: Westwood State: MA Zip Code: 02090 Phone: (814) 335-0763 Fax: (413) 562-5317 E-mail: [email protected] Does this project meet or exceed a mandatory EIR threshold (see 301 CMR 11.03)? Yes No If this is an Expanded Environmental Notification Form (ENF) (see 301 CMR 11.05(7)) or a Notice of Project Change (NPC), are you requesting: a Single EIR? (see 301 CMR 11.06(8)) Yes No a Special Review Procedure? (see 301CMR 11.09) Yes No a Waiver of mandatory EIR? (see 301 CMR 11.11) Yes No a Phase I Waiver? (see 301 CMR 11.11) Yes No (Note: Greenhouse Gas Emissions analysis must be included in the Expanded ENF.) Which MEPA review threshold(s) does the project meet or exceed (see 301 CMR 11.03)? ENF and Mandatory EIR ñ 301 CMR 11.03(3)(a)(4): structural alteration of an existing dam that causes any decrease in impoundment capacity ñ 301 CMR 11.03(1)(a): alteration of one or more acres of bordering vegetated wetland; ñ 301 CMR 11.03(3)(a)(1)(b): alteration of ten or more acres of any other wetlands ENF and Other MEPA Review if the Secretary so Requires ñ 301 CMR 11.03(3)(b)(1)(b): alternation of 500 or more linear feet of inland bank ñ 301 CMR 11.03(3)(b)(1)(d): alternation of >5,000 sf of bordering vegetated wetlands ñ 301 CMR 11.03(3)(b)(1)(f): alternation of >1/2 acres of any other wetland (LUW, BLSF, Riverfront Area) Effective January 2011 Which State Agency Permits will the project require? ñ Chapter 253 Dam Safety Permit (MassDCR) ñ Section 401 Water Quality Certification (MassDEP) ñ Wetlands Protection Act Order of Conditions (MassDEP) ñ Waterways Chapter 91 License (MassDEP) Identify any financial assistance or land transfer from an Agency of the Commonwealth, including the Agency name and the amount of funding or land area in acres: EEA Dam & Seawall Repair and Removal Fund: $75,000 MassDER Priority project funding: $48,000 (FY21) Summary of Project Size Existing Change Total & Environmental Impacts LAND Total site acreage 300 acres +/- New acres of land altered 75 acres +/- Acres of impervious area 2.5 acres +/- No change 2.5 acres +/- Square feet of new bordering 1,564,000 square vegetated wetlands alteration feet+/- Square feet of new other wetland 1,700,000 square feet+/- alteration Acres of new non-water dependent N/A use of tidelands or waterways STRUCTURES Gross square footage N/A N/A N/A Number of housing units N/A N/A N/A Maximum height (feet) N/A N/A N/A TRANSPORTATION Vehicle trips per day N/A N/A N/A Parking spaces N/A N/A N/A WASTEWATER Water Use (Gallons per day) N/A N/A N/A Water withdrawal (GPD) N/A N/A N/A Wastewater generation/treatment N/A N/A N/A (GPD) Length of water mains (miles) N/A N/A N/A Length of sewer mains (miles) N/A N/A N/A Has this project been filed with MEPA before? Yes (EEA # ) No Has any project on this site been filed with MEPA before? Yes (EEA # ) No - 2 - GENERAL PROJECT INFORMATION – all proponents must fill out this section PROJECT DESCRIPTION: Describe the existing conditions and land uses on the project site The Wheelwright Pond Dam is a run-of-river dam located on the Ware River between Hardwick and New Braintree, Massachusetts. The dam was associated with an adjacent mill and is located approximately 3.1 river-miles downstream of Wheelwright Road (Route 32) in Ware and approximately 1.8 river-miles upstream of Hardwick Road in Hardwick and New Braintree. The Ware River flows through Worcester and Hampden County, and joins with the Quaboag River in Palmer to form the Chicopee River. The Chicopee River is the largest single tributary to the Connecticut River. The drainage area to Wheelwright Pond Dam is approximately 129 square miles and is primarily composed of forested areas. The U.S. Geological Survey (USGS) StreamStats application shows that less than 10-percent of the drainage area is composed of developed (urban) land as defined by the 2011 National Land Cover Database (2011) (the dataset used by StreamStats), and approximately 10-percent of the drainage area is composed of wetlands. In the area of the dam, an upstream gravel mining and washing business (R. J. McDonald, Inc.) draws water from the impoundment formed by the dam. A railroad bridge crosses the river approximately 2.8 miles upstream from the dam, and Wheelwright Road (Route 32) crosses the river upstream from the railroad bridge, approximately 3.1 miles upstream from the dam. In between RJ McDonald and the railroad bridge, the river corridor is surrounded by forest and wetland areas. Barre Falls Dam (MA00962) in Hubbardston, Massachusetts, is located on the Ware River approximately 10 miles upstream of Wheelwright Pond Dam. Barre Falls Dam is a U.S. Army Corps of Engineers (USACE) flood control dam that “substantially reduces flooding along the Ware, Chicopee, and Connecticut Rivers”1. The closest dam located upstream of Wheelwright Pond Dam along the Ware River is South Barre Mill Pond Dam (MA00091) in Barre, Massachusetts, located approximately 4.5 miles upstream of Wheelwright Pond Dam. The closest downstream dam on the Ware River is the Ware Industries Upper Dam (MA00594) in Ware, Massachusetts, located approximately nine (9) miles downstream of Wheelwright Pond Dam. Wheelwright Pond Dam does not affect flood levels or operations at the neighboring dams. The dam is surrounded by the remains of the former mill complex at the right abutment on the west side, and the clearing for the runway of the Tanner-Hiller Airport is located on the east side. The dam is a significant obstruction on a particularly scenic and undeveloped section of the Ware River. The impoundment extends upstream from the dam approximately 2.5 miles, and immediately downstream from the dam the river is artificially wide to accommodate discharges from the spillway. Although the impoundment is narrow, the presence of the dam floods a portion of what would be surrounding floodplain and wetlands, including former oxbows, and separates stream segments that would total approximately 130 miles of connected river corridor and habitat. Removal of the dam would serve to benefit ecological communities, state-listed special concern species, and human recreation. The dam is also deteriorated; it was inspected and rated in Poor condition during a required dam safety inspection as long ago as 2006. The dam owner began compliance with subsequent dam safety orders, including having performed a Phase II inspection completed in 2009-2010. Although the dam has subsequently been found in marginally improved condition, the dam owner is not financially able to implement needed repairs. In 2018, given the significantly important natural resources along the Ware River near the project site and the potential for restoring ecological processes impacted by the dam, the Massachusetts Department of Fish and Game Division of Ecological Restoration (MassDER) selected removal of the Wheelwright Pond Dam as a Priority Project. A team of project partners with shared goals, including MassDER, the East Quabbin Land Trust (EQLT), and the dam owner (Riatto Industrial Park, Inc.), subsequently assembled. 1 www.nae.usace.army.mil/Missions/Civil-Works/Flood-Risk-Management/Massachusetts/Barre-Falls/ - 3 - In addition to ecological restoration and public safety benefits through dam removal, the project partners seek to increase recreational opportunities by developing a new river crossing for the MassCentral Rail Trail, which will provide a critical link between Central and Western Massachusetts. Successful accomplishment of these goals also requires that adverse impacts to infrastructure that have developed around the impoundment be appropriately mitigated. This protect partner group, led by MassDER, has worked to identify resources of concern that may be adversely impacted by the dam removal and develop strategies to avoid, minimize, or mitigate these impacts so that the project can proceed without significant adverse impacts. Please refer to the EENF narrative for additional project details. Describe the proposed project and its programmatic and physical elements: This run-of-river dam consists of several distinct components, with a total length of approximately 500 feet, and a maximum structural height of approximately 17 feet. Beginning at the right (west) abutment, the primary spillway extends approximately 75 across the river, then angles approximately 22 degrees upstream, and then continues left approximately 65 feet. This section of spillway is ogee in shape and approximately 10 feet in height. The date of construction is unknown, although design or construction information is shown on drawings prepared by the Worcester County Commissioners dated March 8, 1921.
Recommended publications
  • Fishway Ladder
    FREQUENTLY ASKED QUESTIONS A. Fishway B. Riverwalk C. DNR Compliance with NR 333 D. Dam Removal E. Property Issues F. Fish and Aquatic Life G. Wildlife H. Recreational Use A. Fishway 1. What is the estimated cost to build a fishway at Bridge Street dam? The engineering consultant, Bonestroo, has estimated the cost at $1.3 million per the NOAA grant. 2. If the fishway is constructed next year, will it have to be rebuilt when the dam needs to be removed and replaced? Essentially no. Most of the fishway is a separate upstream structure and will not be impacted by demolition and construction of a new dam. The fishway entrance area may need to be modified if a new dam is installed or if the dam abutments are altered. 3. Why is the fishway being constructed on the west bank of the river? The west bank allows land owned by the Village of Grafton to be used for a portion of the channel alignment. Furthermore, the heaviest construction will likely be in the area currently owned by the Village (penetration of the west dam abutment). Other advantages include the appeal to tourists able to view fish entering and ascending the fishway from the riverwalk, and the known presence of shallow bedrock helping assure good foundation characteristics. Furthermore, the historic mill race crosses the area, and a portion of the mill race alignment may assist with fishway construction. 4. How long will it take to complete the construction of the fishway? The fishway will be completed by late fall of 2010.
    [Show full text]
  • Fish Passage Engineering Design Criteria 2019
    FISH PASSAGE ENGINEERING DESIGN CRITERIA 2019 37.2’ U.S. Fish and Wildlife Service Northeast Region June 2019 Fish and Aquatic Conservation, Fish Passage Engineering Ecological Services, Conservation Planning Assistance United States Fish and Wildlife Service Region 5 FISH PASSAGE ENGINEERING DESIGN CRITERIA June 2019 This manual replaces all previous editions of the Fish Passage Engineering Design Criteria issued by the U.S. Fish and Wildlife Service Region 5 Suggested citation: USFWS (U.S. Fish and Wildlife Service). 2019. Fish Passage Engineering Design Criteria. USFWS, Northeast Region R5, Hadley, Massachusetts. USFWS R5 Fish Passage Engineering Design Criteria June 2019 USFWS R5 Fish Passage Engineering Design Criteria June 2019 Contents List of Figures ................................................................................................................................ ix List of Tables .................................................................................................................................. x List of Equations ............................................................................................................................ xi List of Appendices ........................................................................................................................ xii 1 Scope of this Document ....................................................................................................... 1-1 1.1 Role of the USFWS Region 5 Fish Passage Engineering ............................................
    [Show full text]
  • Operation Glen Canyon Dam Spiliway: Summer 1983
    7jq Reprinted from the Proceedings of the Conference Water for Resource Development, HY Di v. /ASCE Coeur d'Alene, Idaho, August 14-17, 1984 Operation of Glen Canyon Dam Spiliways - Summer 1983 Philip H. Burgi 1/, M., ASCE, Bruce M. Moyes 2/, Thomas W. Gamble 3/ Abstract. - Flood control at Glen Canyon Do, is provided by a 41-ft (12.5-rn) diameter tunnel spillway in each abutment. Each spillway is designed to pass 138 000 ft3/s (3907.7 m3/s). The spillways first operated in 1980 and had seen very little use until June 1983. In early June the left spiliway was operated for 72 hours at 20 000 ft3/s (566.3 m3/s). After hearing a rumbling aoise in the left spillway, the radial gates were closed and the tunnel was quickly inspected. Cavitation damage had occurred low in the vertical bend, resulting in removal of approximately 50 yd3 (38.2 rn3) of concrete. Flood flows continued to fill the reservoir. Both spillways were operated releasing a total of 1 626 000 acre-ft (2.0 x m3) over a period of 2 months. Exteri- sive cavitation damage occurred in both spiliways in the vicinity of the vertical bend. Introduction. - The tunnel spiliways are open channel flow type with two 40- by 52.5-ft (12.2- by 16.0-rn) radial gates to control releases to each tunnel. Each spillway consists of a 41-ft (12.5-rn) diameter inclined section, a vertical bend, and 1000 ft (304.8 m) of horizontal tunnel followed by a flip bucket.
    [Show full text]
  • Ashley National Forest Visitor's Guide
    shley National Forest VISITOR GUIDE A Includes the Flaming Gorge National Recreation Area Big Fish, Ancient Rocks Sheep Creek Overlook, Flaming Gorge Painter Basin, High Uinta Wilderness he natural forces that formed the Uinta Mountains are evident in the panorama of geologic history found along waterways, roads, and trails of T the Ashley National Forest. The Uinta Mountains, punctuated by the red rocks of Flaming Gorge on the east, offer access to waterways, vast tracts of backcountry, and rugged wilderness. The forest provides healthy habitat for deer, elk, What’s Inside mountain goats, bighorn sheep, and trophy-sized History .......................................... 2 trout. Flaming Gorge National Recreation Area, the High Uintas Wilderness........ 3 Scenic Byways & Backways.. 4 Green River, High Uintas Wilderness, and Sheep Creek Winter Recreation.................... 5 National Geological Area are just some of the popular Flaming Gorge NRA................ 6 Forest Map .................................. 8 attractions. Campgrounds ........................ 10 Cabin/Yurt Rental ............... 11 Activities..................................... 12 Fast Forest Facts Know Before You Go .......... 15 Contact Information ............ 16 Elevation Range: 6,000’-13,528’ Unique Feature: The Uinta Mountains are one of the few major ranges in the contiguous United States with an east-west orientation Fish the lakes and rivers; explore the deep canyons, Annual Precipitation: 15-60” in the mountains; 3-8” in the Uinta Basin high peaks; and marvel at the ancient geology of the Lakes in the Uinta Mountains: Over 800 Ashley National Forest! Acres: 1,382,347 Get to Know Us History The Uinta Mountains were named for early relatives of the Ute Indians. or at least 8,000 years, native peoples have Sapphix and son, Ute, 1869 huntedF animals, gathered plants for food and fiber, photo courtesy of First People and used stone tools, and other resources to make a living.
    [Show full text]
  • Dam Awareness May 2018
    Dam Awareness May 2018 Introduction There is a general lack of knowledge, understanding, and awareness of dams and their risks, leaving those most affected by dams unprepared to deal with the impacts of their failures. This fact sheet provides a general overview of dams for consideration and use by the intended audience, based on their situation. Responsibility and Liability for Dam Safety Dams are owned and operated by individuals, private and public organizations, and various levels of government (federal, state, local, tribal). The responsibility for operating and maintaining a safe dam rests with the owner. Common law holds that the storage of water is a hazardous activity. Maintaining a safe dam is a key element in preventing failure and limiting the liability that an owner could face. The extent of an owner’s liability varies from state to state and depends on statutes and case law precedents. Federally owned and regulated dams are subject to federal regulations and guidelines and applicable federal and state laws. Owners can be fiscally and criminally liable for any failure of a dam and all damages resulting from its failure. Any uncontrolled release of the reservoir, whether the result of an intentional release or dam failure, can have devastating effects on persons, property, and the environment (FEMA, 2016a). Any malfunction or abnormality outside the design assumptions and parameters that adversely affect a dam’s primary function of impounding water is considered a dam failure. Lesser degrees of failure can progressively lead to or heighten the risk of a catastrophic failure, which may result in an uncontrolled release of the reservoir and can have a severe effect on persons and properties downstream (FEMA, 2016b).
    [Show full text]
  • Structural Alternatives for Tdg Abatement at Grand Coulee Dam
    STRUCTURAL ALTERNATIVES FOR TDG ABATEMENT AT GRAND COULEE DAM FEASIBILITY DESIGN REPORT OCTOBER 2000 STRUCTURAL ALTERNATIVES FOR TDG ABATEMENT AT GRAND COULEE DAM FEASIBILITY DESIGN REPORT October, 2000 Prepared for U. S. Bureau of Reclamation Pacific Northwest Region by Kathleen H. Frizell and Elisabeth Cohen Bureau of Reclamation Technical Service Center Denver, Colorado Table of Contents Table of Contents ................................................... i Executive Summary ................................................. ix Acknowledgments ..................................................xiii Background .......................................................1 Introduction .......................................................2 Grand Coulee Dam ..................................................2 TDG Evaluation for Existing Conditions ...................................3 Flow Mixing .................................................4 Existing Outlet Works TDG Generation .............................5 Feasibility Design Discharge and Tailwater ...........................7 Feasibility Designs for Structural Alternatives ................................8 Hydraulic Modeling ............................................9 Outlet Works Model .....................................9 Forebay Pipe with Cascade Model ..........................10 Cover and Extend Mid-level Outlet Works (Alternative 1) ................11 Description ...........................................11 Maintenance Issues ...............................12 Hydraulic and Total
    [Show full text]
  • Cavitation Damage
    Cavitation Damage Best Practices in Dam and Levee Safety Risk Analysis Part F – Hydraulic Structures Chapter F-3 Last modified June 2017, presented July 2019 Outline • Cavitation Basics • Case Histories • Typical Event Trees • Key Considerations • Analytical Methods • Defensive Measures F-3 2 Objectives • Understand the mechanisms that cause Cavitation Damage • Understand how to construct an event tree to evaluate the potential for major cavitation damage related failure • Understand how to estimate potential for major cavitation damage and understand the progression mechanism to failure F-3 3 Key Concepts • Cavitation damage is a time dependent process • Cavitation potential can be estimated by computing a cavitation index • Cavitation damage potential is dependent on other factors including the air concentration in flow, the durability of materials, irregularities along the flow surface, and flow durations • Cavitation damage has resulted in significant damage at several large federal dams F-3 4 Cavitation Basics F-3 5 Cavitation Basics 6 Cavitation Basics • Cavitation occurs in high velocity flow, where water pressure is reduced locally because of an irregularity in the flow surface • As vapor cavities move into a zone of higher pressure, they collapse, sending out high pressure shock waves • If the cavities collapse near a flow boundary, there will be damage to the material at the boundary (cyclical loading induced fatigue failure - - - Long duration) 7 Cavitation Basics Phases of Cavitation • Incipient Cavitation – occasional cavitation
    [Show full text]
  • GLOSSARY of TERMS for DAMS Abutment
    GLOSSARY OF TERMS FOR DAMS Abutment – That part of the valley side or concrete walls against which the dam is constructed. An artificial abutment is sometimes constructed where there is no suitable natural abutment. The wall between a spillway or gate structure and the embankment can also be referred to as an abutment. (Also see Spillway Abutment) Alterations – Changes in the design or configuration of the dam that may affect the integrity or operation of the dam and thereby have a potential to affect the safety of persons, property, or natural resources. (Also see Reconstruction) Appurtenant Works – Structures or machinery auxiliary to dams which are built for operation and maintenance purposes (e.g., outlet works, spillway, powerhouse, tunnels, etc.). Auxiliary Spillway (Emergency Spillway) – A secondary spillway designed to operate only during large flood events; an auxiliary gate is a standby or reserve gate only used when the normal means to control water are not available or at capacity. Boil – An upward disturbance in the surface layer of soil caused by water escaping under pressure from behind or under a dam or a levee. The boil may be accompanied by deposition of soil particles (usually silt) in the form of a ring around the area where the water escapes. Breach – An opening or a breakthrough of a dam sometimes caused by rapid erosion of a section of earth embankment by water; dams can be breached intentionally to render them incapable of impounding water. Capacity (Hydraulic Capacity) – Amount of water a dam can convey through designed spillway structures, typically expressed in cubic feet per second (cfs).
    [Show full text]
  • Fish Ladders for Lower Monumental Dam Snake River, Washington
    c TECHNICAL REPORT NO. 109-1 FISH LADDERS FOR LOWER MONUMENTAL DAM SNAKE RIVER, WASHINGTON HYDRAULIC MODEL INVESTIGATIONS BY L.Z. PERKINS DECEMBER 1973 SPONSORED BY U.S. ARMY ENGINEER DISTRICT WALLA WALLA CONDUCTED BY DIVISION HYDRAULIC LABORATORY U.S. ARMY ENGINEER DIVISION, NORTH PACIFIC CORPS OF ENGINEERS BONNEVILLE, OREGON THIS DOCUMENT HAS BEEN APPROVED FOR PUBLIC RELEASE Destroy this report when no longer needed. Do not return it to the originator. The findings in this report are not to be construed as an offic Department of the Army position unless so designated by other authorized documents. 92063535 C\ TECHNICAL REPORT N®. 109-1 7 FISH LADDERS FOR LOWER MONUMENTAL DAM SNAKE RIVER, WASHINGTON ' ^ HYDRAULIC MODEL INVESTIGATIONS ^ BY 7 L.Z. PERKINS !? DECEMBER 1973 SPONSORED BY U.S. ARMY ENGINEER DISTRICT WALLA WALLA CONDUCTED BY ^piVISION HYDRAULIC LABORATORY U.S. ARMY ENGINEER DIVISION, NORTH PACIFIC ^ CORPS OF ENGINEERS BONNEVILLE, OREGON THIS DOCUMENT HAS BEEN APPROVED FOR PUBLIC RELEASE PREFACE The hydraulic model studies that are described in this report were requested by the U. S. Army Engineer District, Walla Walla, in a letter dated 28 December 1962 to the Chief, Bonneville Hydraulic Laboratory, U. S. Army Engineer District, Portland. The model tests were made from April to November 1962 at Bonneville Hydraulic Laboratory, Bonneville, Oregon, under the general direction of the Portland District Engineer and Mr. L. R. Metcalf, who was in charge of the Hydraulic Section of the Portland District. The Bonneville Hydraulic Laboratory was renamed the North Pacific Division Hydraulic Laboratory when it was transferred to the U.
    [Show full text]
  • Flaming Gorge Dam
    Memorandum To: Regional Director, Bureau of Reclamation, Upper Colorado Regional Office, Salt Lake City, Utah Area Manager, Bureau of Reclamation, Provo Area Office, Provo, Utah Area Manager, Western Area Power Administration, Salt Lake City, Utah From: Field Supervisor, Utah Field Office Fish and Wildlife Service Salt Lake City, Utah Subject: Final Biological Opinion on the Operation of Flaming Gorge Dam In accordance with section 7 of the Endangered Species Act (ESA) of 1973, as amended (16 U.S.C. 1531 et seq.), and the Interagency Cooperation Regulations (50 CFR 402), this transmits the Fish and Wildlife Service's (Service) final biological opinion for impacts to federally listed endangered species for Reclamation’s proposed action to operate Flaming Gorge Dam to protect and assist in recovery of populations and designated critical habitat of the four endangered fishes found in the Green and Colorado River Basins. Reference is made to your February 1, 2005, correspondence (received in our Utah Field office on February 1, 2005) requesting initiation of formal consultation for the subject project. Based on the information presented in the biological assessment and the Operation of Flaming Gorge Environmental Impact Statement that you provided, I concur that the proposed action may adversely effect the threatened Ute ladies’- tresses ( Spiranthes diluvialis) and the endangered Colorado pikeminnow (Ptychocheilus lucius ), humpback chub ( Gila cypha ), bonytail ( Gila elegans ), and razorback sucker ( Xyrauchen texanus ) and critical habitat. Based on the information provided in the biological assessment, I also concur that the proposed operation of Flaming Gorge Dam may affect, but is not likely to adversely affect, the bald eagle (Haliaeetus leucocephalus ) and southwestern willow flycatcher ( Empidonax traillii extimus ).
    [Show full text]
  • Spillway Erosion
    Spillway Erosion Best Practices in Dam and Levee Safety Risk Analysis Part D – Embankments and Foundations Chapter D-2 Last modified June 2017, presented July 2019 Objectives • Understand the mechanisms that affect spillway erosion • Understand how to construct an event tree to represent spillway erosion • Understand the considerations that make this potential failure mode more/less likely • Understand the differences and limitations of the models used to quantify erosion of rock and soil D-2 2 Key Concepts – Spillway Erosion • Recognize that the failure progression is duration dependent (judgement required in evaluating rate of erosion, duration of loading, etc.) • Understand the difference between erosion of a uniform material and that of a varied geology • There are multiple methods available for estimating erosion/scour potential • Scour is complicated and cross-disciplinary • This failure mechanism can be linked to the likelihood of other failure modes (e.g. control section stability, spillway chutes, tunnels and stilling basins) D-2 3 Outline • Overview of the Process • Case Histories • Typical Event Tree • Key Factors Affecting Vulnerability • Analytical Methods • Crosswalk to Other Potential Failure Modes D-2 4 Overview of the Process D-2 5 Spillway Erosion/Scour Process • Turbulence Production • Impinging Jet • Submerged Jet • Back Roller • Hydraulic Jump • Boundary Eddy Formation • Particle Detachment • Brittle Failure • Fatigue Failure • Block Removal (Ejection or Peeling) Bollaert (2010) • Abrasion • Tensile Block Failure Annandale
    [Show full text]
  • Design Optimization of Spillways at Baihetan Hydroelectric Dam
    Design Optimization of Spillways at Baihetan Hydroelectric Dam Oskar Dahl Jack Lönn Master of Science Thesis KTH School of Industrial Engineering and Management Energy Technology EGI_2016-049 EKV1148 Division of Heat and Power Technology SE-100 44 STOCKHOLM Master of Science Thesis EGI_2016-049 EKV1148 Design Optimization of Spillways at Baihetan Hydroelectric Dam Oskar Dahl Jack Lönn Approved Examiner Supervisor 2016-06-20 Björn Laumert James Yang Commissioner Contact person Energiforsk AB & Vattenfall AB James Yang Abstract China’s economic prosperity has led to a massive development in the hydropower sector. The Baihetan hydropower project is an ongoing construction and will become the third largest hydroelectric power plant in the world in regards to generating capacity and is projected to be finished in the year 2020. For every fault that an investment this massive has, it will lead to enormous cost and safety risks. Therefore the standards for every detail are especially high to ensure the success of its future operation. One of the risks is from the water jet impact on the downstream stilling basin that can cause erosion on the riverbed. The evaluation of this risk has previously been carried out by an experimental scaled model at the Department of Hydraulic Engineering at Tsinghua University in Beijing, China. This thesis will however evaluate the potential of exposing these risks and analyzing methods to minimize them through Computational Fluid Dynamics analysis. A Computational Fluid Dynamics model of a surface hole spillway was created in order to be compared and validated against the experimental results. The results in longitudinal direction are in good agreement with the experimental results, with an accuracy of the numerical model being 91% for the longitudinal distance and 98% for the longitudinal spread.
    [Show full text]