Table 5

1 January 2000


Table 5 Current physical safety problems associated with the ten dams surveyedNote: * On the basis of ten dams
Dam components Actual problems Details of problems Percentage of dams*
Reservoir Inability to store design water capacity Sediment accumulation; Irrigation gate leakage; Spillway leakage 100%
Crest Overtopping Inaccurate estimation of hydrographical parameters; Spillway is blocked; Flooding is over the design flood capacity; The top is constructed lower than designed 60%
Settlement on the crest Traffic damage; Animal burrowing activities; Instability of the embankment 80%
Transverse cracking The dam foundation is depressed; Instability of the embankment; Shrinkage of surface materials; Materials are low quality 20%
Longitudinal cracking Water in the reservoir increases or decreases suddenly. This sudden change of water level creates depression on the top; The dam foundation is depressed; Slide occurs on the embankment 40%
Ruts along the crest Traffic damage; The movement of foundation 30%
Upstream slope Seepage under the foundation The quality of material is low. Hence, water is eroding the material; Rodent activity; Geological assessment is inaccurate 20%
Slide and slump The lack or loss of embankment material; Rodent activity; Erosion; Traffic damage; Downstream slope is too steep 80%
Sinkholes The movement of foundation create holes; Material is seeped; Animal burrows 20%
Downstream slope Seepage through the embankment Rodent activity creates open pathway through embankment; The abutment is not properly designed and constructed 70%
Seepage at the abutment The abutment is not properly designed and constructed; Plants/trees are not removed completely in construction 30%
Slide and slump The lack of or loss of embankment material; Rodent activity; The downstream slope is too steep 80%
Spillway Eroded spillway Erosion; The gradient of the channel is too steep 20%
Blocked spillway Soil and stone erosion; Trees and plants; Inaccurate design 50%
Outlet Eroded outlet Outlet is too small; Conduit is eroded; Foundation movement 20%
Leaking and breaking Valve is broken; Vandalism; Outlet is too old 40%



Privacy Policy
We have updated our privacy policy. In the latest update it explains what cookies are and how we use them on our site. To learn more about cookies and their benefits, please view our privacy policy. Please be aware that parts of this site will not function correctly if you disable cookies. By continuing to use this site, you consent to our use of cookies in accordance with our privacy policy unless you have disabled them.