Flood Warning and Damages in Alice Springs: Part 1 Executive Summary. Part 2 Tangible Damages Part 3 Intangible Damages & Emergency Procedures
Handmer, John; Smith, D. I.; Greenaway, Mark
E-Publications; E-Books; PublicationNT; Report ; 53/1989
Made available via the Publications (Legal Deposit) Act 2004 (NT).
Power and Water Authority
Report ; 53/1989
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Technical Report WRA89053 Viewed at 03:02:00 on 18/02/2010 Page 23 of 139. I I I I I I I I I I I I I I I I I I I I 7 Property Affected The ANUF-LOOD proper-:y data base includes ground and floor hc,i:::rhts~ TtIhen these are combined with the information on the surface of the :-3.ximum flood lev'el for the Easter 1988 event, the numbers :: affected properties are obtained .. ..' ...... th ' , '.... oF -=1 . _~ogecner W.!.Ln .J.e i'".elgnL. 0 .... ove::L oar, or ove:r-grouna, t-l"J')-r~inn f"~ each ~-~ner~y "'--,"0-:; "".L, " .. :--_-'~-_<.... .... If a small nU!'1ber c: properties are flooded it lS possible to obtain inormati:~ on damage by questionnaires and inspection of all t~e effected properties. With larger numbers this is not: ;)!_~a.ct ical and averaging C'lethods are employed. This is ;-;asic to the ANUFLOOD p:cocedure. The problem is to obtain data to construct realistic stage-damage curves ~or the property involved. For Alice Springs, for ;:he ea:-lier Power and Itlater study and the current study, a si~gle stage damage curve was used for all residential 9rOper~j. Such curves can relate to potential or actual direct da:c.age. Tn the former, the damage is assessed as a I'wo~s~-caset. scenario. No allowance is made for the reduction of damage due to the actions of the residents ie lifting material ohto tables, removing material to flood free premises, etc. In conttast 'tactual" damage is the loss sustained after actions are taken to reduce damage; it will always be equal to or less than the potential loss. E'or tlood studies t::at are undertaken without the data available from an ac~ual flood event it is normal practice to use potential da:cage. Estimates of actual damage are more appropriace whe~ assessing the damage from a specific eve:1t. The major protlem for da~age estimation in Alice Springs is to estab:ish the most appropriate stage-damage curve. This will be considered separately for the residential and corr~ercial sectors. Overall the residential stage-damage curves, described in Figure 2.3 1 match the information gathered from the interviews. Residential stage da~age curve The potential damage curve, for direct losses, for residential property used in the original Power and Water Authority study of ~lice Springs is illustrated in Figure 2.2. It also shows the "standard" single ANU2LOOD value. It is clear that the Alice Springs values are much higher, by a factor of three or four. The Alice Springs residential curves are also larger than those obtained from other Australian st'~dies. It is clearly necessary to refine these curves in order to obtain a more precise value for the Easter 1988 losses. A major diffe~ence between the earlier Alice springs values and those fr~~ elsewhere, concerns the values attributed to the s:~uctural (building) component of the