Narellan Creek Overland Flood Study (Vol 1) - Flipbook - Page 87
Narellan Creek Catchment
Flood Study
Table 21
Floodplain Risk Precinct Definitions
Floodplain Risk Precinct
High Flood Risk
Mainstream
Definition
High provisional flood hazard during
the 1% AEP flood based on Figure L2
of the Floodplain Development
Manual (2005). Also includes areas
with significant evacuation difficulties
in 1% AEP flood or areas exposed to
significant consequences during
events larger than the 1% AEP flood.
Areas within or
immediately adjacent to
a defined watercourse
Remaining area below the FPL and
not defined as 8high9 risk.
Areas within or
immediately adjacent to
a defined watercourse
Medium Flood Risk
≥H4 in 1% AEP flood
Low flood island in 1%
AEP flood
≥H5 in 0.2% AEP flood
Within the FPA (as
defined in Section 7.2),
but not 8high9 risk.
All remaining areas within the PMF
that are not 8high9 or 8medium9 risk.
Low Flood Risk
High Flood Risk
Adopted Criteria
Areas within or
immediately adjacent to
a defined watercourse
Within the PMF extent
but not classified as 8high9
or 8medium9 risk
Includes all floodway areas and all
areas of the floodplain subject to
overland flooding with flood depths
greater than 0.5m in a 1% AEP event.
Areas located away from
a defined watercourse
Floodway in 1% AEP flood
Depths > 0.5 metres in
1% AEP flood
Overland
Low Flood Risk
Comprises all the remaining areas of
the floodplain subject to overland
flooding in the 1% AEP event (i.e.,
with flood depths between 0.3m to
0.5m) and above the 1% AEP event
and within the PMF extent.
73
Areas located away from
a defined watercourse
Within the PMF extent
and not classified as
8high9 risk
