Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and...
Transcript of Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and...
![Page 1: Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and repair of wildlife or animal damage Removal of floating debris from outlet works Repair](https://reader034.fdocuments.in/reader034/viewer/2022050207/5f5a7da1b9d90b02ff21a344/html5/thumbnails/1.jpg)
1
Dam Safety Work Group Department of Conservation & Recreation
Division of Soil & Water Conservation
Impounding Structure Maintenance
Presented by:
Ken Turner, District Dam Safety Consultant February 24, 2011
![Page 2: Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and repair of wildlife or animal damage Removal of floating debris from outlet works Repair](https://reader034.fdocuments.in/reader034/viewer/2022050207/5f5a7da1b9d90b02ff21a344/html5/thumbnails/2.jpg)
2
What Will Be Covered
Maintenance Related Liability
What causes dams to fail
Class Objectives
Maintenance Responsibility
![Page 3: Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and repair of wildlife or animal damage Removal of floating debris from outlet works Repair](https://reader034.fdocuments.in/reader034/viewer/2022050207/5f5a7da1b9d90b02ff21a344/html5/thumbnails/3.jpg)
3
General Understanding of Maintenance
Maintenance Activities
Dam Maintenance Factors
Dam Maintenance Activities
Undesirable vegetation
Examples of Good & Bad Maintenance
What will be covered, continued
![Page 4: Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and repair of wildlife or animal damage Removal of floating debris from outlet works Repair](https://reader034.fdocuments.in/reader034/viewer/2022050207/5f5a7da1b9d90b02ff21a344/html5/thumbnails/4.jpg)
4
Learning Objectives
Why Dams Fail What maintenance is needed The difference between well maintained & poorly maintained
![Page 5: Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and repair of wildlife or animal damage Removal of floating debris from outlet works Repair](https://reader034.fdocuments.in/reader034/viewer/2022050207/5f5a7da1b9d90b02ff21a344/html5/thumbnails/5.jpg)
5
Why should I worry about maintenance?
If being a good steward of the environment is not enough of a reason then consider this,
LIABILITY
Under the law the dam owner is liable for damage downstream if their dam breaks and someone dies or property damage occurs. Legal penalties for negligence are much higher.
![Page 6: Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and repair of wildlife or animal damage Removal of floating debris from outlet works Repair](https://reader034.fdocuments.in/reader034/viewer/2022050207/5f5a7da1b9d90b02ff21a344/html5/thumbnails/6.jpg)
6
Proper maintenance of a dam is like that of an older vehicle in need of extensive repair:
If left unmaintained, repair is expensive.
If maintenance and repair are performed as needed, costs are minimized.
![Page 7: Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and repair of wildlife or animal damage Removal of floating debris from outlet works Repair](https://reader034.fdocuments.in/reader034/viewer/2022050207/5f5a7da1b9d90b02ff21a344/html5/thumbnails/7.jpg)
7
What causes embankments to fail? A. Erosion caused by Overtopping of the Embankment
Timberlake Dam in Campbell County, VA 2 Dead, >$1 Million
B. Erosion due to Piping through the Embankment
Grand Teton Dam in Idaho 11 Dead, >$1 Billion
C. Problems that cause the dam to not function as designed.
D. External Issues like Earthquakes or Terrorism that the dam was
not designed to survive.
![Page 8: Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and repair of wildlife or animal damage Removal of floating debris from outlet works Repair](https://reader034.fdocuments.in/reader034/viewer/2022050207/5f5a7da1b9d90b02ff21a344/html5/thumbnails/8.jpg)
8
Maintenance Responsibility
The responsibility for proper operation, maintenance, and inspection of most dams falls upon dam owners.
![Page 9: Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and repair of wildlife or animal damage Removal of floating debris from outlet works Repair](https://reader034.fdocuments.in/reader034/viewer/2022050207/5f5a7da1b9d90b02ff21a344/html5/thumbnails/9.jpg)
9
Dam Maintenance Factors
Factors that affect proper maintenance of dams:
• Classification -- the higher the hazard class the higher the standard of duty and standard of are required
• Type of dam – earthen vs concrete
• Function of dam – flood control, water resource
• Size of dam – 6 ft. vs 70 ft. and storage volume
![Page 10: Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and repair of wildlife or animal damage Removal of floating debris from outlet works Repair](https://reader034.fdocuments.in/reader034/viewer/2022050207/5f5a7da1b9d90b02ff21a344/html5/thumbnails/10.jpg)
10
Dam Maintenance Factors (Cont.)
Factors that affect proper maintenance of dams:
• Prevailing climatic conditions – subject to ice damage
• Watershed characteristics – debris producer or not
• Spillway system characteristics – earthen or concrete
![Page 11: Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and repair of wildlife or animal damage Removal of floating debris from outlet works Repair](https://reader034.fdocuments.in/reader034/viewer/2022050207/5f5a7da1b9d90b02ff21a344/html5/thumbnails/11.jpg)
11
Dam Maintenance Activities
Nurturing (growing) and mowing grassed areas
Removal of woody vegetation
Control and repair of wildlife or animal damage
Removal of floating debris from outlet works
Repair of eroded/scoured areas
![Page 12: Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and repair of wildlife or animal damage Removal of floating debris from outlet works Repair](https://reader034.fdocuments.in/reader034/viewer/2022050207/5f5a7da1b9d90b02ff21a344/html5/thumbnails/12.jpg)
12
Dam Maintenance Activities (Cont.)
Repair of embankment surface erosion
Opening and closing of outlet gates to ensure operability
Painting and repair of metal components
Grouting and sealing concrete joints/cracks
Removal and protection of spalling concrete
![Page 13: Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and repair of wildlife or animal damage Removal of floating debris from outlet works Repair](https://reader034.fdocuments.in/reader034/viewer/2022050207/5f5a7da1b9d90b02ff21a344/html5/thumbnails/13.jpg)
13
Dam Maintenance Activities (Cont.)
Repair of wave berm erosion
Stabilization of outlet channels
Repair and replacement of warning signs
Maintenance of instrumentation/ monitoring systems
![Page 14: Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and repair of wildlife or animal damage Removal of floating debris from outlet works Repair](https://reader034.fdocuments.in/reader034/viewer/2022050207/5f5a7da1b9d90b02ff21a344/html5/thumbnails/14.jpg)
14
Dam Maintenance Activities (Cont.)
Maintenance of emergency access routes
Removal of diseased trees on lake rim
Removal of sediment deposits at inlet
Control and removal of aquatic growth
![Page 15: Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and repair of wildlife or animal damage Removal of floating debris from outlet works Repair](https://reader034.fdocuments.in/reader034/viewer/2022050207/5f5a7da1b9d90b02ff21a344/html5/thumbnails/15.jpg)
15
Typical Issues Beyond an Owners Capability
Seepage (piping) Through the embankment From around the outfall pipe or cradle Leaking into the outfall pipe Separated joints in the outfall pipe Deep seated slope failure Structural fill Cracks, bulges or depressions
![Page 16: Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and repair of wildlife or animal damage Removal of floating debris from outlet works Repair](https://reader034.fdocuments.in/reader034/viewer/2022050207/5f5a7da1b9d90b02ff21a344/html5/thumbnails/16.jpg)
16
Undesirable Vegetation: Tall Grass, Brush & Noxious Weeds
Weeds Make Inspections more difficult
Weeds also provides a haven for borrowing animals Grass that attracts wildlife (deer). Deer & cattle take the same path and kill grass.
![Page 17: Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and repair of wildlife or animal damage Removal of floating debris from outlet works Repair](https://reader034.fdocuments.in/reader034/viewer/2022050207/5f5a7da1b9d90b02ff21a344/html5/thumbnails/17.jpg)
17
Undesirable Vegetation: Trees
Trees can blow over in high winds and severely damage the embankment.
Tree roots penetrate the embankment and alter its structural integrity.
Tree roots can become pathways for seepage,
especially if the tree dies and roots rot.
![Page 18: Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and repair of wildlife or animal damage Removal of floating debris from outlet works Repair](https://reader034.fdocuments.in/reader034/viewer/2022050207/5f5a7da1b9d90b02ff21a344/html5/thumbnails/18.jpg)
18
Embankments Upstream, Downstream & Top
![Page 19: Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and repair of wildlife or animal damage Removal of floating debris from outlet works Repair](https://reader034.fdocuments.in/reader034/viewer/2022050207/5f5a7da1b9d90b02ff21a344/html5/thumbnails/19.jpg)
19
Tree Problems
Trees on Downstream Embankments
Trees on Upstream Embankments
![Page 20: Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and repair of wildlife or animal damage Removal of floating debris from outlet works Repair](https://reader034.fdocuments.in/reader034/viewer/2022050207/5f5a7da1b9d90b02ff21a344/html5/thumbnails/20.jpg)
20
Trees within 25’ of the Toe
After Removal
Trees & Roots
![Page 21: Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and repair of wildlife or animal damage Removal of floating debris from outlet works Repair](https://reader034.fdocuments.in/reader034/viewer/2022050207/5f5a7da1b9d90b02ff21a344/html5/thumbnails/21.jpg)
21
Trees within 25’ of the Groins
Trees & Roots (Cont.)
Mower Sliding on Roots Damaged Embankment
![Page 22: Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and repair of wildlife or animal damage Removal of floating debris from outlet works Repair](https://reader034.fdocuments.in/reader034/viewer/2022050207/5f5a7da1b9d90b02ff21a344/html5/thumbnails/22.jpg)
22
Erosion Rills
Damage from Animal Grazing Terresetting
Erosion
![Page 23: Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and repair of wildlife or animal damage Removal of floating debris from outlet works Repair](https://reader034.fdocuments.in/reader034/viewer/2022050207/5f5a7da1b9d90b02ff21a344/html5/thumbnails/23.jpg)
23
Wave Erosion Wake or Wind
Erosion (Cont.)
4 x 4 or ATV Damage
![Page 24: Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and repair of wildlife or animal damage Removal of floating debris from outlet works Repair](https://reader034.fdocuments.in/reader034/viewer/2022050207/5f5a7da1b9d90b02ff21a344/html5/thumbnails/24.jpg)
24
Erosion (Cont.)
Animal Paths & Motorcycle Trails
![Page 25: Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and repair of wildlife or animal damage Removal of floating debris from outlet works Repair](https://reader034.fdocuments.in/reader034/viewer/2022050207/5f5a7da1b9d90b02ff21a344/html5/thumbnails/25.jpg)
25
Groundhog, Muskrat, Skunk, or Fox Damage
Skunk Den
Groundhog Burrow
![Page 26: Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and repair of wildlife or animal damage Removal of floating debris from outlet works Repair](https://reader034.fdocuments.in/reader034/viewer/2022050207/5f5a7da1b9d90b02ff21a344/html5/thumbnails/26.jpg)
26
Wetland Plants/Color Change
Sparse Vegetation
Seepage and/or Wet Spots on the Toe
Ground Cover or Unusual Plant Growth
![Page 27: Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and repair of wildlife or animal damage Removal of floating debris from outlet works Repair](https://reader034.fdocuments.in/reader034/viewer/2022050207/5f5a7da1b9d90b02ff21a344/html5/thumbnails/27.jpg)
27
Debris on Embankment
Trees pieces parts
Decks, Docks Etc.
![Page 28: Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and repair of wildlife or animal damage Removal of floating debris from outlet works Repair](https://reader034.fdocuments.in/reader034/viewer/2022050207/5f5a7da1b9d90b02ff21a344/html5/thumbnails/28.jpg)
28
No grass on top of dams
Driveways
![Page 29: Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and repair of wildlife or animal damage Removal of floating debris from outlet works Repair](https://reader034.fdocuments.in/reader034/viewer/2022050207/5f5a7da1b9d90b02ff21a344/html5/thumbnails/29.jpg)
29
Wet areas on embankment above toe
Slope Failures & Wet Areas
Slope Failure Beginning
![Page 30: Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and repair of wildlife or animal damage Removal of floating debris from outlet works Repair](https://reader034.fdocuments.in/reader034/viewer/2022050207/5f5a7da1b9d90b02ff21a344/html5/thumbnails/30.jpg)
30
Slope Failures (Cont.)
Deep-seated Slope Failure Not an Owner repair issue.
![Page 31: Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and repair of wildlife or animal damage Removal of floating debris from outlet works Repair](https://reader034.fdocuments.in/reader034/viewer/2022050207/5f5a7da1b9d90b02ff21a344/html5/thumbnails/31.jpg)
31
Embankments, Maintenance Review
A. Repair Erosion in any form B. Ground Cover – Good Fescue Sod 2”-6” long optimum C. Remove Trees (on the dam or within 25’) D. Remove Burrowing Animals, fill dens E. Cracks, Settlement, Bulges, Slope Failure – Call Engineer F. Seepage or Wet Areas on Toe – Call Engineer G. Seepage in Groins – Call Engineer
Note: Trees on the dam with roots larger than 1” in diameter must be grubbed out, lost material replaced, & the disturbed areas stabilized.
![Page 32: Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and repair of wildlife or animal damage Removal of floating debris from outlet works Repair](https://reader034.fdocuments.in/reader034/viewer/2022050207/5f5a7da1b9d90b02ff21a344/html5/thumbnails/32.jpg)
32
Principal Spillways A.K.A. Riser Towers
2 Stage Concrete Open Top Design
2 Stage Baffled Concrete Riser
![Page 33: Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and repair of wildlife or animal damage Removal of floating debris from outlet works Repair](https://reader034.fdocuments.in/reader034/viewer/2022050207/5f5a7da1b9d90b02ff21a344/html5/thumbnails/33.jpg)
33
Riser Towers
Debris Blocking/Surrounding Riser Tower
Single Stage Concrete Riser Tower with Solid Top
Concrete Pipe Riser with Trash Rack & Anti-vortex Device
![Page 34: Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and repair of wildlife or animal damage Removal of floating debris from outlet works Repair](https://reader034.fdocuments.in/reader034/viewer/2022050207/5f5a7da1b9d90b02ff21a344/html5/thumbnails/34.jpg)
34
Principal Spillway
Tower with Debris on Top & In Riser Tower Weir Opening
Single Stage Solid Top Riser CMP Riser
![Page 35: Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and repair of wildlife or animal damage Removal of floating debris from outlet works Repair](https://reader034.fdocuments.in/reader034/viewer/2022050207/5f5a7da1b9d90b02ff21a344/html5/thumbnails/35.jpg)
35
Riser Towers, Maintenance Review
A. Repair Spalling or Broken Concrete B. Rebar exposed? C. Repair Rusting Parts D. Clear Debris in Openings E. Keep Gate Operable F. Repair Leaks G. Clear Sediment at Gate
![Page 36: Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and repair of wildlife or animal damage Removal of floating debris from outlet works Repair](https://reader034.fdocuments.in/reader034/viewer/2022050207/5f5a7da1b9d90b02ff21a344/html5/thumbnails/36.jpg)
36
OSHA has safety standards regarding entry into confined spaces. Training & special equipment is required. Perhaps, it would be better to have a professional inspect & repair damage to risers and large outfall structures.
CAUTION
![Page 37: Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and repair of wildlife or animal damage Removal of floating debris from outlet works Repair](https://reader034.fdocuments.in/reader034/viewer/2022050207/5f5a7da1b9d90b02ff21a344/html5/thumbnails/37.jpg)
37
Another extreme hazard in working around riser pipes is that flowing water can exert high pressure on things around it. I once saw a video of a jon boat being pulled into a 30 inch riser pipe. Please consider that when removing debris blocking the pipe if the water level is elevated.
CAUTION
![Page 38: Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and repair of wildlife or animal damage Removal of floating debris from outlet works Repair](https://reader034.fdocuments.in/reader034/viewer/2022050207/5f5a7da1b9d90b02ff21a344/html5/thumbnails/38.jpg)
38
Auxiliary Spillways A.K.A. Emergency Spillways
Entrance to ES
ES Downstream From Control Section
![Page 39: Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and repair of wildlife or animal damage Removal of floating debris from outlet works Repair](https://reader034.fdocuments.in/reader034/viewer/2022050207/5f5a7da1b9d90b02ff21a344/html5/thumbnails/39.jpg)
39
Emergency Spillway
Entranced Blocked with Trees
Obstructions in Spillway
Gravel Road Through ES
![Page 40: Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and repair of wildlife or animal damage Removal of floating debris from outlet works Repair](https://reader034.fdocuments.in/reader034/viewer/2022050207/5f5a7da1b9d90b02ff21a344/html5/thumbnails/40.jpg)
40
Fence at Control Section
Obstruction in Lower Section
![Page 41: Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and repair of wildlife or animal damage Removal of floating debris from outlet works Repair](https://reader034.fdocuments.in/reader034/viewer/2022050207/5f5a7da1b9d90b02ff21a344/html5/thumbnails/41.jpg)
41
Obstruction & Severe Cattle Damage
Electric Pole, Tree & Garden Plot
![Page 42: Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and repair of wildlife or animal damage Removal of floating debris from outlet works Repair](https://reader034.fdocuments.in/reader034/viewer/2022050207/5f5a7da1b9d90b02ff21a344/html5/thumbnails/42.jpg)
42
Trees blocking ES Outfall Channel
Depressed Dirt Road Through ES & Power Pole with Guy Wire
![Page 43: Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and repair of wildlife or animal damage Removal of floating debris from outlet works Repair](https://reader034.fdocuments.in/reader034/viewer/2022050207/5f5a7da1b9d90b02ff21a344/html5/thumbnails/43.jpg)
43
Low Level Outfall, A.K.A. Bottom Draw Gate
Low Head Gate by Waterman
Stop Logs
![Page 44: Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and repair of wildlife or animal damage Removal of floating debris from outlet works Repair](https://reader034.fdocuments.in/reader034/viewer/2022050207/5f5a7da1b9d90b02ff21a344/html5/thumbnails/44.jpg)
44
Low Level Outfall Gate, cont’d
High Pressure Gate (Rodney Hunt) Typical Gate Operators
Poorly Maintained
![Page 45: Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and repair of wildlife or animal damage Removal of floating debris from outlet works Repair](https://reader034.fdocuments.in/reader034/viewer/2022050207/5f5a7da1b9d90b02ff21a344/html5/thumbnails/45.jpg)
45
Low Level Outfall Gate
Gate Controls
Hydraulically Activated Knife Gate
![Page 46: Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and repair of wildlife or animal damage Removal of floating debris from outlet works Repair](https://reader034.fdocuments.in/reader034/viewer/2022050207/5f5a7da1b9d90b02ff21a344/html5/thumbnails/46.jpg)
46
An extreme hazard in working around low level gates is that flowing water can exert high pressure on things around it. I once saw a small deer pulled through a 12” x 12” rebar screen, into an 18” pipe, through an 18” valve and deposited into the plunge pool over 300’ from the entry point. Please consider that when working near an open gate.
CAUTION
![Page 47: Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and repair of wildlife or animal damage Removal of floating debris from outlet works Repair](https://reader034.fdocuments.in/reader034/viewer/2022050207/5f5a7da1b9d90b02ff21a344/html5/thumbnails/47.jpg)
47
Plunge Pool Outfall Channels
![Page 48: Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and repair of wildlife or animal damage Removal of floating debris from outlet works Repair](https://reader034.fdocuments.in/reader034/viewer/2022050207/5f5a7da1b9d90b02ff21a344/html5/thumbnails/48.jpg)
48
Plunge Pool
Rip - Rap Displaced by Tree Stump and Roots
![Page 49: Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and repair of wildlife or animal damage Removal of floating debris from outlet works Repair](https://reader034.fdocuments.in/reader034/viewer/2022050207/5f5a7da1b9d90b02ff21a344/html5/thumbnails/49.jpg)
49
Plunge Pool & Outfall Channel
Rip Rap Missing Or Displaced
Toe Drains are Not Plugged And Have Rodent Guards
![Page 50: Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and repair of wildlife or animal damage Removal of floating debris from outlet works Repair](https://reader034.fdocuments.in/reader034/viewer/2022050207/5f5a7da1b9d90b02ff21a344/html5/thumbnails/50.jpg)
50
Toe Drain Blocked – Not flowing freely
Spalling Concrete
![Page 51: Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and repair of wildlife or animal damage Removal of floating debris from outlet works Repair](https://reader034.fdocuments.in/reader034/viewer/2022050207/5f5a7da1b9d90b02ff21a344/html5/thumbnails/51.jpg)
51
Beaver Damage
High Water Level, Note Dead Trees in Background
Water Backing Up into Outfall Pipe
Photo By Don Nelson
![Page 52: Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and repair of wildlife or animal damage Removal of floating debris from outlet works Repair](https://reader034.fdocuments.in/reader034/viewer/2022050207/5f5a7da1b9d90b02ff21a344/html5/thumbnails/52.jpg)
52
Beaver Damage
Water Backing Up into Outfall Pipe
Unseen Issues: Inside the riser not visible from the outside. Under water pyramid of debris.
![Page 53: Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and repair of wildlife or animal damage Removal of floating debris from outlet works Repair](https://reader034.fdocuments.in/reader034/viewer/2022050207/5f5a7da1b9d90b02ff21a344/html5/thumbnails/53.jpg)
53
Outfall Pipe, Plunge Pool & Outfall Channel, Maintenance review A. Repair Spalling, cracking or scaling B. Exposed rebar C. Joints displaced or offset, contact engineer D. Leaking into pipe E. Leaking under pipe F. Plunge pool rip rap in place G. Erosion around edge of pool H. Erosion of channel banks
![Page 54: Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and repair of wildlife or animal damage Removal of floating debris from outlet works Repair](https://reader034.fdocuments.in/reader034/viewer/2022050207/5f5a7da1b9d90b02ff21a344/html5/thumbnails/54.jpg)
54
Unusual Structures
Potential Piping Sources Sluice Gate to Mill
Air Vent Pipe
![Page 55: Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and repair of wildlife or animal damage Removal of floating debris from outlet works Repair](https://reader034.fdocuments.in/reader034/viewer/2022050207/5f5a7da1b9d90b02ff21a344/html5/thumbnails/55.jpg)
55
Instrumentation
Staff Gauge
IFLOW Device Monitoring
Well
![Page 56: Dam Safety Work Group Department of Conservation ... · Removal of woody vegetation Control and repair of wildlife or animal damage Removal of floating debris from outlet works Repair](https://reader034.fdocuments.in/reader034/viewer/2022050207/5f5a7da1b9d90b02ff21a344/html5/thumbnails/56.jpg)
56
Questions?
The End