What are the risks?

Unless we undertake the full schedule of proposed repairs at each of the 13 damaged sites, lower Waitaki residents face a higher risk that erosion and flooding could cause damage to people and property than before.

However, we want to gauge what the community believes is an acceptable level of risk, if any.

The graph in the previous section shows the average river flow over the last 12 months, which is roughly indicative of what might happen this year. Essentially, when the river flow goes above the risk levels indicated in the graph, there is a higher chance of more erosion at the existing sites. This in turn means a greater risk of erosion and flooding, both of land adjacent to the river and the wider lower Waitaki area.

Residual risk

If scenario A, B or any other partial repair option is chosen, it should be noted that there will be an elevated level of residual risk as a consequence. Partially repaired sites and damaged sites are more vulnerable to further erosion and flood flows are less likely to be contained within the main river channel. This could cost more if it is decided to repair at a later date.