Response to Info_Request_sept2014

Fish Passage

4. The western tributary is a minor waterway for fish passage. Given the extent of works
in the waterway and the proposed works are an integral part of the modelling,
Council recommends the applicant gain written support from DAFF for the proposed
works.

Response:

The proposed waterway modifications for flood mitigation and natural channel remediation do
not constrict the waterway or involve any waterway barriers that would inhibit fish passage.
As such there is no trigger for Waterway Barrier Operational Works application. DAFF
policies do not trigger any applications under SPA for these works. As there is less than
500m3 of excavation or 150m3 of fill within the waterway bed and banks a Riverine
Protection Permit application will not need to be submitted to DNRM.

Swale Flow

5. Please confirm that the maximum flow through the bio retention swales in a Q100
event do not exceed 1.0m/s in accordance with Healthy Waterways Design
Guidelines.

Response:

The swale velocity is very low at 0.24m/s in a Q100, therefore it complies with Healthy Waterways
design guidelines.

Footbridge Flows

6. Please confirm Q100 flood depths over the footbridge. It is unclear of the blockage
factor that has been applied to the bridge and handrail and its impact on flood levels.

Response:

Please refer to Brisbane Stormwater Management (BSM) response on page 7 of the updated
study dated 15-9-14.

Hydrologic Regime

7. The hydrologic regime is proposed to be changed over 2 Pearson’s road in a minor
event. Please provide owners consent from 2 Pearsons Road for this change to
hydrological flows on their property.

a. Nocomment on the environmental impact of this (2 Pearsons Road) change
to the hydrological flow has been provided.

Response to Item 7:

An overall reduction in flow as shown in Table 11 of the BSM report is considered to provide

an advantage for the adjacent owner of Lot 3 RP113733. Council approves minor changes to
flows on adjacent properties every time a new interlot drainage line is approved. This recently
occurred upstream of proposed Stage 5 of this subdivision where properties on Wilgee Court

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