Slope Stability Report · EXE22/0013

PRACTICE NOTE GUIDELINES FOR LANDSLIDE RISK MANAGEMENT 2007
APPENDIX C: LANDSLIDE RISK ASSESSMENT
QUALITATIVE TERMINOLOGY FOR USE IN ASSESSING RISK TO PROPERTY

QUALITATIVE MEASURES OF LIKELIHOOD

AD PISKINES AnieRL Erenabenty Implied Indicative Landslide iescriplisi Daatical
Recurrence Interval Lt =

‘The event is expected to occur over the design life
100 years em will probably occur under adverse conditions over the |} ip, y
POSSIBLE c

‘The event could occur under ad verse conditions over the design life.

10,000 years ier 7 might occur under very adverse circumstances over the UNLIKELY
‘The event is conceivable but only under exceptional circumstances . 7
100 yens RARE E

The event is inconceivable or fanciful over the design life BARELY CREDIBLE

Note: (1) The table should be used from left 0 right; use Approximate Annual Probability or Description to assign Descriptor, not vice versa.

 

QUALITATIVE MEASURES OF CONSEQUENCES TO PROPERTY

Approximate Cost of Damage
Notional Descriptor Level
Boundary

Structure(s) completely destroyed andor large scale damage requiring major engineering works for J catasrromic |
stabilisation. Could cause at least one adjacent ty major consequence damag Sols

stabilisation works. Could cause at least one adjacent property medium consequence damage
Moderate damage to some of structure, and/or significant part of site requiring large stabilisation works.

In ive
Value
| om Extensive damage to most of structure, and/or extending beyond site boundaries requiring significant

 

Could cause at last one adjacent ty minor consequence damag, LOD
imi ge to part of structure, and/or part of site requiring some reinstatement stabilisation works. MINOR [ 4 |
= Littk damage. (Note for high probability event (Almost Certain), this category may be subdivided ata 3
ee notional boundary of 0.1%. See Risk Matrix.) BEISMERANE
Notes: (2) The Approximate Cost of Damage is expressed as a percentage of market value, being the cost of the improved value of the affected property which includes the land plus he
unaffected structures,

3) The Approximate Cost is to be an estimate of the direct cost of the damage, such as the cost of reinstatement of the damaged portion of the property (land plus structures), stabilisation
works required to render the site to tolerable risk level for the landslide which has occurred and professional design fees, and consequential costs such as legal fees, temporary
acommadation. It does not include additional stabilisation works to address other landslides which may affect the property.

a The table shoukl be used fram left to right; use Approximate Coat of Damage or Description to assign Descriptor, not vice versa

a1 Australian Geomechanics Vol 42 No 1 March 2007