1909-13367 SRA referral response approved docs

This is 2.58m3/s less than the existing case.


4.2.14 1 in 50 0 R es ult s ( D e v elop ed w ith blo c ka g e)

The peak water level during the above event at reporting point 1 was 106.62m AHD. The peak water
level at point 2 is 105.54m AHD. The peak water level at point 1 is 0.01m less that the developed case
without blockage. Point 2 shows an increase in peak water elevation of 0.15m.

The peak flow at flow line 10 was 50.02m 3/s.
This is 4.46m3/s less than the existing case.


4.2.15 1 in 2 00 0 R es ult s ( D e v elop ed no b loc k ag e)

The peak water level during the above event at reporting point 1 was 106.69m AHD. The peak water
level at point 2 is 105.78m AHD. Point 1 shows a decrease in peak water elevation of 0.04m, while the
peak water elevation at point 2 has decreased by 0.08m.
The peak flow at flow line 10 was 55.10m 3/s.

This is 4.22m3/s less than the existing case.


4.2.16 1 in 20 0 0 Re su lt s ( D ev e lop ed w ith b lo ck a ge)

The peak water level during the above event at reporting point 1 was 106.75m AHD. The peak water
level at point 2 is 105.78m AHD. The applied blockage factors have resulted in an increase in peak
water elevation at point 1 of 0.06m and 0.21m at point 2.

The peak flow at flow line 10 was 56.90m3/s.

This is 2.42m3/s less than the existing case.


4.2.17 PM P R es ult s ( D ev e lo ped no bl oc k ag e)

The peak water level during the above event at reporting point 1 was 107.79m AHD. The peak water
level at point 2 is 106.70m AHD. Point 1 has an increase in peak water elevation of 0.15m. Point 2
shows an increase in peak water elevation of 0.01m.
The peak flow at flow line 10 was 182.72m 3/s.

This is 8.40m3/s less than the existing case.


4.2.18 PM P R es ult s ( D ev e lo ped w ith b lo c kag e)

The peak water level during the above event at reporting point 1 was 107.81m AHD. The peak water
level at point 2 is 106.71m AHD. The applied blockage factors show an increase of 0.02m at point 1
and 0.01m at point 2.

The peak flow at flow line 10 was 179.65m 3/s.

This is 11.47m3/s less than the existing case.


4. 3   Af flu x R es ult s an d Di sc us si on

Afflux for the above models has been measured using the GIS package “Global mapper”. Each 2D
water elevation grid has been imported into the above package and the differences between the



                                              Flood Study                                          30
S19-007                                122 & 144 Myall St, Cooroy