Bridge Health Index

In reply to the Hon. A. KOUTSANTONIS (West Torrens) (24 November 2020). (Estimates Committee A)

The Hon. C.L. WINGARD (Gibson—Minister for Infrastructure and Transport, Minister for Recreation, Sport and Racing): I have been advised:

The health index is a numerical rating of 0 to 100 that reflects element inspection data in relation to the asset value of a structure or group of structures. The premise of the health index is that each structural element has an initial asset value when new. An element may deteriorate to a lower condition state, reducing its asset value. With maintenance or rehabilitation, the condition of the element is likely to improve and the corresponding asset value to increase.

Each road structure is typically inspected at a routine interval which may be four years or eight years depending on the type of structure. During the field inspection the element condition at that time is determined. Once the condition distribution is known, the current element value can be determined for all elements on the structure. The health index for the structure is the ratio (from 1 to 100) of the current element value to the replacement element value of all elements on the structure. To apply the health index concept to a group of structures, the entire group is treated as one large structure containing the summation of all element quantities and condition distributions within the group.