1909-13367 SRA referral response approved docs

Flows approaching the development site from the south-west (Myall St and the Bruce highway) begin
to overtop the proposed intersection of Myall St and the proposed bridge during this event. The
maximum depth of flow across the intersection is approximately 0.05m.


4.2.10 2 % Ae p Re su lt s ( D ev elo pe d w ith bl oc k ag e )

The peak water level during the above event at reporting point 1 was 106.44m AHD. The peak water
level at point 2 is 105.14m AHD. The results at points 1 and 2 show a decrease of 0.03m at point 1 and
0.01m at point 2.
The peak flow at flow line 10 was 41.28m3/s.

The above peak flow is as per the above case without blockage.


4.2.11 1 % Ae p Re su lt s ( D ev elo pe d n o b lo 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 105.18m AHD. Point 1 shows no change in peak water elevation. Point 2 shows a
decrease in peak water elevation of 0.03m.

The peak flow at flow line 10 was 44.13m3/s.

This is 2.73m3/s less than the existing case. The above peak water elevation results indicate that the
bridge is not creating a worsening upstream.

Flows approaching the site from the south-west overtop the intersection of Myall St and the proposed
entry way to the development site. The maximum depth of flow across this intersection is approximately
0.05m.

The developed 1% AEP model peak water depth is presented in figure 9 below. See Appendix BC for
all design flood maps.




                                              Flood Study                                          28
S19-007                                122 & 144 Myall St, Cooroy