Avoca Lagoon Floodplain Management Plan

Seven flooding precincts have been identified around the lagoon foreshore. These have been sub-divided into four management areas. These management areas have been classified for flood hazard as: High Hazard - Floodways - Avoca Lagoon beach berm; - Saltwater Creek, from the upstream study boundary to its confluence with Avoca Lagoon (identified as Saltwater Creek floodway); and High Hazard – Low Hazard Floodway (Floodway Investigation area) - Avoca Lagoon at its entrance to the ocean (Floodway/Investigation area); Low Hazard - Flood Storage - Avoca Lagoon and foreshores excepting high hazard areas above. These management areas are illustrated on Figure 2, while Figure 3 provides more detailed information for the Avoca Lagoon entrance area and Figure 4 tables the specific provisions applicable to each of the management areas. Council has adopted a policy of opening the lagoons when water level reaches RL 2.09 m AHD (identified as the let-out-level). Council has, in the past, also adopted a policy that requires new buildings to have floor levels above RL 3.7 m AHD. These two policies effectively constitute Council's current floodplain management practice around Avoca Lagoon. Specific components of the Floodplain Management Plan are outlined in the report