Zambia-Small Dam Inspection Report V1.1.1

• Document status

  Initiated

  In progress

  Complete

  Approved

• Dam Name

• Dam location

• Type of inspection

  Select Weekly Monthly Annual Informal Special Other

  • Weekly
  • Monthly
  • Annual
  • Informal
  • Special
  • Other

• Conducted on

  Date

• Officer(s) name, email and phone number

• Photo of the inspection team

  Media

• Attendees

• Weather conditions

  Select Sunny Cloudy Windy Light rain Heavy read

  • Sunny
  • Cloudy
  • Windy
  • Light rain
  • Heavy read

• Ground Moisture Condition

  Dry

  Wet

• Reservoir level: what is the distance in meters from crest to water level?

• Photo of overall water level (reservoir from distance)

  Media

• Spillage?

  Yes

  No

• approximate discharge (m3/s)

• General notes

Slope cover

• Poor quality or improperly sized riprap deteriorates and does not protect the slope against wave action or erosion. Important to insure/restore the protection of the upstream slope. Wave can displace riprap allowing erosion or over-steepening of the bank.

• Inadequate ground cover (loss of riprap material, stone weathering/alteration)?

  No

  Yes

  Unknown

  N/A

• Location?

• Photo

  Media

• Any changes respect to previous visit?

  No

  Yes

  Unknown

  N/A

• Describe

Cracks on the embankment slope

• Slope instability and differential settlement between zones or within the embankment may cause longitudinal/transversal cracks.

• Cracks?

  No

  Yes

  Unknown

  N/A

• Longitudinal or transversal?

  Transversal

  Longitudinal

• Location?

• Crack dimensions? (length, width and depth)

• Photo of the crack

  Media

• Any changes respect to previous visit?

  No

  Yes

  Unknown

  N/A

• Describe

Sinkholes, depressions, slides, or bulges

• Internal erosion or piping of embankment materials or the foundation of the dam can cause sinkholes/depressions. Internal erosion or piping can lead to dam failure.

• Sinkholes, depressions, slides, or bulges?

  No

  Yes

  Unknown

  N/A

• Location?

• Dimensions (length and depth)

• Photo

  Media

• Any changes respect to previous visit?

  No

  Yes

  Unknown

  N/A

• Describe

Material Erosion

• Water from intense rainstorms carries surface materials down the slope and results in continuous troughs, rills, gullies, etc. Erosion can lead to severe deterioration of the slope

• Erosion?

  No

  Yes

  Unknown

  N/A

• Location?

• Dimensions (length and depth)

• Photo

  Media

• Any changes respect to previous visit?

  No

  Yes

  Unknown

  N/A

• Describe

Animal damage

• Borrowing and other animals can be quite dangerous to the structural integrity and performance of the dam. It is essential that these animals and their activities to be controlled to insure proper functioning of the dam.

• Animal burrows?

  No

  Yes

  Unknown

  N/A

• Location?

• What type of animal damage?

• Photo

  Media

• Any changes respect to previous visit?

  No

  Yes

  Unknown

  N/A

• Describe

Vegetation

• Trees and brush should never be allowed to grow on upstream slope of the dam. The root systems of trees can be a potential hazard by allowing seepage pathways to develop through a dam.

• Trees and/or brush??

  No

  Yes

  Unknown

  N/A

• Location?

• Photo

  Media

• Any changes respect to previous visit?

  No

  Yes

  Unknown

  N/A

• Describe

General comment(s)

• Add general comment(s) or further details

• Photo

  Media

Cracks along the top of dam

• Slope instability and differential settlement between zones or within the embankment may cause longitudinal/transversal cracks.

• Cracks?

  No

  Yes

  Unknown

  N/A

• Longitudinal or transversal?

  Transversal

  Longitudinal

• Location?

• Crack dimensions? (length, width and depth)

• Photo of the crack

  Media

• Any changes respect to previous visit?

  No

  Yes

  Unknown

  N/A

• Describe

Sinkholes, depressions, slides, or bulges

• Internal erosion or piping of embankment materials or the foundation of the dam can cause sinkholes/depressions. Internal erosion or piping can lead to dam failure.

• Sinkholes, depressions, slides, or bulges?

  No

  Yes

  Unknown

  N/A

• Location?

• Dimensions (length and depth)

• Photo

  Media

• Any changes respect to previous visit?

  No

  Yes

  Unknown

  N/A

• Describe

Material erosion

• Water from intense rainstorms carries surface materials down the slope and results in continuous troughs, rills, gullies, etc. Erosion can lead to severe deterioration of the slope

• Erosion?

  No

  Yes

  Unknown

  N/A

• Location?

• Dimensions (length and depth)

• Photo

  Media

• Any changes respect to previous visit?

  No

  Yes

  Unknown

  N/A

• Describe

Animal damage

• Borrowing and other animals can be quite dangerous to the structural integrity and performance of the dam. It is essential that these animals and their activities to be controlled to insure proper functioning of the dam.

• Animal burrows?

  No

  Yes

  Unknown

  N/A

• Location?

• What type of animal damage?

• Photo

  Media

• Any changes respect to previous visit?

  No

  Yes

  Unknown

  N/A

• Describe

General comment(s)

• Add general comment(s) or further details

• Photo

  Media

Vegetative cover

• Grass cover is a very effective and inexpensive means to prevent the erosion of the embankment surfaces.

• Poor vegetative cover?

  No

  Yes

  Unknown

  N/A

• Describe

• Photo

• Any changes respect to previous visit?

  No

  Yes

  Unknown

  N/A

• Describe

Cracks on the embankment slope

• Slope instability and differential settlement between zones or within the embankment may cause longitudinal/transversal cracks.

• Cracks?

  No

  Yes

  Unknown

  N/A

• Longitudinal or transversal?

  Transversal

  Longitudinal

• Location?

• Crack dimensions? (length, width and depth)

• Photo of the crack

  Media

• Any changes respect to previous visit?

  No

  Yes

  Unknown

  N/A

• Describe

Sinkholes, depressions, slides, or bulges

• Internal erosion or piping of embankment materials or the foundation of the dam can cause sinkholes/depressions. Internal erosion or piping can lead to dam failure.

• Sinkholes, depressions, slides, or bulges?

  No

  Yes

  Unknown

  N/A

• Location?

• Dimensions (length and depth)

• Photo

  Media

• Any changes respect to previous visit?

  No

  Yes

  Unknown

  N/A

• Describe

Material Erosion

• Water from intense rainstorms carries surface materials down the slope and results in continuous troughs, rills, gullies, etc. Erosion can lead to severe deterioration of the slope

• Erosion?

  No

  Yes

  Unknown

  N/A

• Location?

• Dimensions (length and depth)

• Photo

  Media

• Any changes respect to previous visit?

  No

  Yes

  Unknown

  N/A

• Describe

Animal damage

• Borrowing and other animals can be quite dangerous to the structural integrity and performance of the dam. It is essential that these animals and their activities to be controlled to insure proper functioning of the dam.

• Animal burrows?

  No

  Yes

  Unknown

  N/A

• Location?

• What type of animal damage?

• Photo

  Media

• Any changes respect to previous visit?

  No

  Yes

  Unknown

  N/A

• Describe

Vegetation

• Trees and brush should never be allowed to grow on upstream slope of the dam. The root systems of trees can be a potential hazard by allowing seepage pathways to develop through a dam.

• Trees and/or brush??

  No

  Yes

  Unknown

  N/A

• Location?

• Photo

  Media

• Any changes respect to previous visit?

  No

  Yes

  Unknown

  N/A

• Describe

Seepage areas or wet areas

• Seepage with sediment at the seepage exit indicates potential internal erosion of the dam embankment or foundation

• Seepage areas or wet areas?

  No

  Yes

  Unknown

  N/A

• Location?

• Extension?

• Any evidence of materials being transported by seepage flow (such as discoloured water or sediment deposit)?

  No

  Yes

  Unknown

  N/A

• Describe

• Photo

  Media

• Any changes respect to previous visit?

  No

  Yes

  Unknown

  N/A

• Describe

General comment(s)

• Add general comment(s) or further details

• Photo

  Media

Vegetation at dam toe

• Uncontrolled vegetation on and around dams can hinder inspection and lead to serious structural damage, significant maintenance costs, and possible failure. Control of proper vegetation is an important part of dam maintenance.

• Uncontrolled vegetation at the dam toe?

  No

  Yes

• Location?

• Describe

• Photo

  Media

• Any changes respect to previous visit?

  No

  Yes

  Unknown

  N/A

• Describe

Soft or spongy zones

• Soft or spongy zones at the downstream toe of the dam are a sign of uncontrolled seepage which could result in internal erosion or piping. Immediate action is required!

• Soft or spongy zones?

  No

  Yes

  Unknown

  N/A

• Locations?

• Describe

• Photo

  Media

• Any changes respect to previous visit?

  No

  Yes

  Unknown

  N/A

• Describe

Boils

• A boil at the downstream toe of the dam is a sign of uncontrolled seepage which could result in internal erosion or piping. Immediate action is required!

• Boils?

  No

  Yes

  Unknown

  N/A

• Location?

• Describe

• Photo

  Media

• Any changes respect to previous visit?

  No

  Yes

  Unknown

  N/A

• Describe

Toe drain

• Toe drain is used to collect seepage from the foundation and embankment and convey it to a free outlet

• Toe drain?

  Yes

  No

  Unknown

  N/A

• Description

• Foundation drain outlet submerged?

  Yes

  No

  Unknown

  N/A

• Foundation drain functional?

  Yes

  No

  Unknown

  N/A

• Estimated flow from drains:

• Any evidence of materials being transported by seepage flow (such as discoloured water or sediment deposit)?

  No

  Yes

  Unknown

  N/A

• Photo

  Media

• Any changes respect to previous visit?

  No

  Yes

  Unknown

  N/A

• Describe

Seepage

• Water has created an open pathway, channel, or pipe through
  the dam. Continued flows can further erode embankment
  and/or foundation materials and lead to dam failure.

• Seepage observed through the embankment outside of designated drain(s)?

  No

  Yes

  Unknown

  N/A

• Seepage clear with no signs of ongoing internal erosion?

  Yes

  No

  Unknown

  N/A

• Rapid piping or erosion of foundation materials could result in failure of the dam. Immediate action is required !

• Location?

• Extension?

• Describe

• Photo

  Media

• Same seepage locations as previous ones?

  Yes

  No

  Unknown

  N/A

• Any changes respect to previous visit?

  No

  Yes

  Unknown

  N/A

• Increase in “wetted area” size?

  No

  Yes

  Unknown

  N/A

• Increase in seepage quantities or turbidity?

  No

  Yes

  Unknown

  N/A

General comment(s)

• Add general comment(s) or further details

• Photo

  Media

• Erosion?

  No

  Yes

  Unknown

  N/A

• Differential movements?

  No

  Yes

  Unknown

  N/A

• Sinkholes, settlements, depressions, slides, or bulges?

  No

  Yes

  Unknown

  N/A

• Cracks?

  No

  Yes

  Unknown

  N/A

• Seepage?

  No

  Yes

  Unknown

  N/A

• Any changes respect to previous visit?

  No

  Yes

  Unknown

  N/A

• Describe

• Add general comment(s) or further details

• Photo

  Media

• Erosion?

  No

  Yes

  Unknown

  N/A

• Differential movements?

  No

  Yes

  Unknown

  N/A

• Sinkholes, settlements, depressions, slides, or bulges?

  No

  Yes

  Unknown

  N/A

• Cracks?

  No

  Yes

  Unknown

  N/A

• Seepage?

  No

  Yes

  Unknown

  N/A

• Any changes respect to previous visit?

  No

  Yes

  Unknown

  N/A

• Describe

• Add general comment(s) or further details

• Photo

  Media

• Spillage?

  Yes

  No

• What is the water depth above the dropping structure?

• Approach channel: Instability of the side channel?

  No

  Yes

  Unknown

  N/A

• Inlet free from debris?

  Yes

  No

  Unknown

  N/A

• Trees and brush around the inlet?

  No

  Yes

  Unknown

  N/A

• Erosion on drop off structure?

  No

  Yes

  Unknown

  N/A

• Erosion on spillway channel walls?

  No

  Yes

  Unknown

  N/A

• Erosion on discharge channel?

  No

  Yes

  Unknown

  N/A

• Any issue concerning the spillway?

  No

  Yes

  Unknown

  N/A

• Describe

  Yes

  No

  Unknown

  N/A

• Photo

  Media

• Any changes respect to previous visit?

  No

  Yes

  Unknown

  N/A

• Describe

• Add general comment(s) or further details

• Photo

  Media

• Outlet operational?

  Select YES, water is coming out already, no need to open YES, when turning weir in the outlet box water comes out NO, when turning weir in the outlet box water does not comes out Don't know, the reservoir level is too low that water cannot come out

  • YES, water is coming out already, no need to open
  • YES, when turning weir in the outlet box water comes out
  • NO, when turning weir in the outlet box water does not comes out
  • Don't know, the reservoir level is too low that water cannot come out

• Seepage from a point adjacent to the oulet?

  No

  Yes

  Unknown

  N/A

• Hole around the point adjacent to the oulet?

  No

  Yes

  Unknown

  N/A

• Describe

• Add general comment(s) or further details

• Photo

  Media

List

• Describe

• Photo

  Media