Appendix 4 - Engineering Report (00012423)

Unit Development 30-32
Doonella Street, Tewantin

T



        1. INTRODUCTION

      Our client, Serina Pty Ltd wishes to redevelop the site at 30-32 Doonella Street,
     Tewantin into a multi dwelling unit complex. At a pre-lodgement meeting with Council
     a number of engineering issues were raised by Council staff. The purpose of this
     report is to address these issues and to provide guidance on the redesign of the
     concept plans to be lodged with Council in support of a Material Change of Use
     Application.

     The site covers two lots with a total area of 2359 m2 and is described as lot 32 on
     RP 893427 and lot 903 on T1631.


        2. PROPOSED DEVELOPMENT

     It is proposed to construct a multi-level unit building with basement car park and
     access off Doonella Street. Council have indicated that the basement level must be
     free draining (i.e. a pump out system will not be allowed). Council records indicate
     there is a drainage pipe from the car park behind the site running through lot 32 on
     RP 893427 and this needs to be investigated. It is anticipated that stormwater
     detention and water quality treatment will be required as part of the development
     works and preliminary sizing of these features has been undertaken by our sub-
     consultant Aquaintel.


        3. SERVICES INFRASTRUCTURE

     The subject site is currently connected to existing water and sewer infrastructure
     located in Doonella Street. These existing services are considered suitable for the
     proposed development.

     As the site is located on the high side of Doonella Street stormwater from the site
     currently drains to the existing kerb and channel and conveyed to existing drainage
     pits in the street.

     A site investigation has revealed that:

           The interlot drainage pipe shown on Council GIS system passing through the
            development site does not exist. The drainage pit in the car park behind the
            site drains towards Sidoni Street, not Doonella Street.
           There is a drainage pit in Doonella Street on the low side of the development
            site (not shown on Council’s GIS) which has an invert level of approximately
            1000mm below the road pavement. Based on the contours on Council’s GIS

     J/N 13672                                                                     June 2015
      Rev C                                                                       Page 1 of 2