2 David Low Way - Attachment 3 - Civil Engineering Assessment - Sheehy 10-8-17

Councils Planning Scheme Policies adequately deal with the requirements for stormwater
drainage to be addressed with the Development Application and Operational Works
Application. If natural channels are ultimately proposed to be utilised for the management of
overland flow, the application for Development Approval will be required to provide flood
modelling that demonstrates that the Council requirements for flood immunity to development
levels have been met.
Any stormwater drainage systems required to convey runoff within the Structure Plan Area is
to be provided in accordance with Queensland Urban Drainage Manual and Council’s
Planning Scheme Policies.

2.6      Sewerage

There is no current Unitywater sewer that services the existing properties within the
development site. The development site lies within the Demand Projection Catchment of the
Noosa STP Sunshine Beach and within the Unitywater Future Connection Area.
Unitywater provided a Services Advice Notice in February 2016 (SAN number 2016006791)
and advised that no provisions have been made in their forward works programme to service
the area with sewerage services. Any changes required must therefore be carried out at no cost
to Unitywater.
Unitywater have advised that sewerage is to be provided to the upstream property boundary to
enable future main extensions. The proposed sewer connection to the development has been
shown to extend to the downstream property within the road reserve and to the upstream
property boundary within a compliant easement running through the allotments. Unitywater
Connections Policy 2016 Sewer Connection Area maps shows no further development on the
east side of David Low Way to be connected to the sewer infrastructure in the future, as this
land is designated “Park, Reserves, National Parks & State Forest”. The extent of the proposed
sewer is therefore compliant with Untiywater requirements.
The Detailed Infrastructure Mapping provided by Unitywater (included in Appendix E)
indicates the existing sewerage assets in the vicinity of the development site. A 300mm
diameter sewer pressure main within David Low Way runs to the front of the development site
and connects to the existing pump station located adjacent to Burgess Creek and to the north
west of the site. A 525mm trunk gravity sewer runs from the north under the road viaduct to
the same pump station.
The development will be serviced by a new sewer connection to the gravity sewer using the
existing manhole adjacent to the Creek. An initial assessment has been carried out to identify
a feasible route for the sewerage reticulation system required to service the proposed
development. This initial assessment is identified on the General Layout and Services Plan in
Appendix B and the Sewer Reticulation Longitudinal Section included in Appendix F. It is
proposed to lay a new gravity sewer connection from the existing 525mm diameter sewer
manhole within the existing road reserve, following the route of the existing footpath, to a
point outside the most northerly property. From a newly constructed manhole the reticulation
sewer will enter the proposed development site and run along the driveway access within a 3m
easement to the most southerly property boundary. Each property will be provided with a
dedicated connection to the reticulation sewer to meet Unitywater requirements. It is expected
that a 150mm uPVC sewer will be required to service the properties.
No trunk sewer works is anticipated for the development.
No other formal discussions have been held with Unitywater at this stage of development
beyond the Services Advice Notice referred to above.



Document No. 8531 Castaways Development-Rev C   Page 7                       Issue Date: 08/08/2017