Build a Dam Workshop

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New Jersey Bureau of Dam Safety Flood Control
Build a Dam Workshop
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Types of Dams

• Embankment
• Earth fill
• Rock fill
• Concrete Gravity
• Masonry Gravity
• Concrete Buttress
• Concrete Arch
• Timber Crib

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Embankment
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Embankment
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Concrete Gravity
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Concrete Gravity
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Buttress
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Buttress
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Concrete Arch
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Concrete Arch
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Timber Crib
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Timber Crib
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Low-Head Dam
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Low-Head Dam
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Low-Head Dam
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What is a this?
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Beaver Dams

• The largest known was discovered near Three
  Forks, Montana, and was 2,140 feet long, 14 feet
  high, and 23 feet thick at the base!

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Embankment Terminology
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Cross Section Terminology
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Why are dams important?
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Why are dams important?
Drinking Water
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Why are dams important?
Flood Control
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Why are dams important?
Power Generation
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Why are dams important?
Recreation
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Why are dams important?
Other...
Merrill Creek Reservoir, Warren County
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Dam Failures

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Teton Dam Failure (Rexburg, ID - 1976)
- 305-foot high, earth and gravel fill
embankment - Designed by the Federal
Bureau of Reclamation
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Early Afternoon June 5, 1976
Billions of Gallons of Water Flow Through Breach
Teton Dam Failure
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Hours later Late Afternoon June 5, 1976
Impoundment Drained
Teton Dam Failure
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Spillway Rehabilitation Alternatives
Spillway Types

• Emergency Spillways
• Auxiliary Spillways
• Primary Spillways

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Spillway Types

• Ogee
• Labyrinth
• Semi-circular
• Broad-Crest Weir
• Sharp-Crested Weir
• Spillway Gates
• Drop Structure
• Riser Structure
• Emergency Spillway

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Ogee Spillway
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Labyrinth Spillway
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Semi-circular Spillway
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Broad-Crested Weir Spillway
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Sharp-Crested Weir Spillway
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Spillway Gates
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Drop-Box / Riser Structure
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Emergency Spillway
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Overtopping Protection
Great Gorge Dam, Vernon, NJ
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Dam Removal
Waubeka Dam, Wisconsin
Photo courtesy of Mike Bruch/Wisconsin DNR Photo
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Fish Ladders
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Historic Issues
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New Jersey Bureau of Dam Safety Flood Control
New Jersey Dam Safety
Questions or Comments?
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New Jersey Bureau of Dam Safety Flood Control
Dam Model Demonstration
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Increase Spillway Efficiency

• We will look at three different spillway types to
  determine which are most efficient for passing
  the most flow.
• Types of Spillway Demonstrated
• Ogee
• Broad-Crested Weir
• Semi-Circular Weir
• Drop Box Conduit

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Increase Spillway Efficiency
Q CLH(3/2)
Broad-Crested Weir
C 3.0
Ogee
C 4.0
Changing spillway geometry alone in this case
would increase spillway capacity by 25
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Increase Spillway Length
Q CLH(3/2)
Semi-Circular
Broad-Crested Weir
L7.0
L 5.75
Changing spillway length by 1.25 alone in this
case would increase spillway capacity by 18
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Drop Box Conduit
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Emergency Spillway
Flows during extreme events
Lower elevation than crest of dam
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New Jersey Bureau of Dam Safety Flood Control
Lets Test it Out ! Dam Model Demonstration