1909-13367 SRA referral response approved docs

The maximum water level at Reporting point 2 was 104.34m AHD. The natural surface level at this
location is 101.81m AHD from available LIDAR information. The maximum flow depth at this location is
2.53m.

The peak flow downstream of the development site as extracted from flow line 10 was 19.37m3/s (see
figure 5 above for the location).
Myall St does not have flood immunity in the 50% AEP event.

The existing rail corridor has immunity in the above event Please refer to appendix BC for details.


4.1.2 20 % Ae p E xi st ing R e sul t s (no b loc k ag e)

The peak water level during the above event at reporting point 1 was 106.12m AHD. The peak water
level at point 2 is 104.65m AHD.
The peak flow at flow line 10 was 28.18m3/s.

The existing rail corridor has immunity in the above event.


4.1.3 10 % Ae p E xi st ing R e sul t s (no b loc k ag e)

The peak water level during the above event at reporting point 1 was 106.20m AHD. The peak water
level at point 2 is 104.84m AHD.

The peak flow at flow line 10 was 31.15m3/s.

The existing rail corridor has immunity in the above event.


4.1.4 5 % Ae p E x ist ing R e s ult s ( n o b lo ck ag e)

The peak water level during the above event at reporting point 1 was 106.33m AHD. The peak water
level at point 2 is 104.98m AHD.

The peak flow at flow line 10 was 37.05m3/s.

The existing rail corridor has immunity in the above event.


4.1.5 2 % Ae p E x ist ing R e s ult s ( n o b lo ck ag e)

The peak water level during the above event at reporting point 1 was 106.47m AHD. The peak water
level at point 2 is 105.15m AHD.

The peak flow at flow line 10 was 45.21m3/s.

The existing rail corridor has immunity in the above event.


4.1.6   1 % Ae p Re su lt s ( no blo ck ag e)

The peak water level during the above event at reporting point 1 was 106.52m AHD. The peak water
level at point 2 is 105.21m AHD.

The 1% AEP maximum flood depths are depicted below in figure 9. A complete set of flood maps for
all events is presented in Appendix BC.

The peak flow at flow line 10 was 46.86m3/s.



                                              Flood Study                                             24
S19-007                                122 & 144 Myall St, Cooroy