M2677 - Information request response

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         1 in 4 maintenance access ramp is provided for each bio retention/ detention basin, while not compromising the
          storage capabilities of the bio-detention basin areas.
         The design includes scour protection which has been provided at the inlets to the basins
         A safety fence will be installed around the perimeter of each basin with a lockable gate to prevent public access.
         Educational signage to inform the public about the functions of the bio basins.
         Updated Landscape plans have been prepared by Blackburne Jackson, which demonstrates the proposed
          landscaping design for each bio basin (refer to Attachment D).

Issue: Rainwater Tanks
The SWMP doesn’t appear to state what areas of communal landscaping are proposed to be irrigated with the captured
roofwater.

Information Required:
2.    Update the SWMP to state all assumptions regarding the rainwater tank and reuse, including a plan show
      communal landscaped areas intended to be irrigated. This is required so that hydraulic services plans can
      accurately reflect the SWMP intent.

Response - Item 2
Refer to Morgan Consulting Engineers response and plans in Attachment A, which includes an updated Site Based
Stormwater Management Plan that outlines the landscaping areas the rainwater tanks are intended to irrigate.

Issue: Flow Concentration
The SWMP proposed bioretention basin B in the North-Eastern corner of the site. This basin design incorporates an
overflow weir from the bioretention basin which would direct flow to both downstream Lot 80 SP 138388 and the
neighbouring Lot 79 SP138388. However, it appears that the existing site contains an existing (dry) basin with an earthen
weir which directs discharge to the driveway on Lot 80 SP 138388 only and not into Lot 79 SP138388.

For Bioretention A, it appears that the high-flow weir encompasses the entire external-facing perimeter of the basin and in
some points interfaces with land which is significantly higher than the existing low-point of the site. The flow over this weir
in the 1%AEP event also appears to be <10mm.

Information Request:
3.     Investigate and confirm the existing discharge patterns from the development site in the North-Eastern corner of
       the proposed development and demonstrate that the design will not result in any changes in flow patterns or
       discharge onto additional land which is not inundated by stormwater runoff from the site in the existing case.




JFP Ref: M2677P                                                                                                    Page 2