Should a 10 % AEP riverine flood coincide with a 1 % AEP storm-tide both sides of the river will be impacted under present day sea-levels. Although the probability of such events coinciding is very low, it is recommended that prior to predicted high Barwon River flows the sea-levels at Portland be examined to ascertain whether a storm-tide is likely to occur, and the timing of this in relation to the expected peak river flows. Section 5.4.1 discusses how the sea-level at Portland can be used to give an indication of the sea-level at the mouth of the Barwon Estuary to warn against potential storm-tide events.

The newly upgraded stormwater pumping station at Barwon Heads along Clifford Parade will aid in managing the effects of river, saline and runoff induced flooding. This area is a low-lying depression that pools water, and three high-capacity pumps have replaced the previous single pump. Although this does not affect the hazard vulnerability, this should be considered in subsequent risk and mitigation assessments. The management triggers are presented in Table 6-5.

Table 6-5     Management triggers - Barwon Heads, Barwon River and Lake Connewarre