Swmp

Table of Contents
1.0       INTRODUCTION ................................................................................................................................... 3
2.0       EXISTING SITE DESCRIPTION ......................................................................................................... 4
3.0       PROPOSED DEVELOPMENT ............................................................................................................. 5
4.0       EXISTING DRAINAGE.......................................................................................................................... 5
   4.1        Existing Drainage Infrastructure ............................................................................................................. 5

   4.2        Existing Drainage Patterns ........................................................................................................................ 6

   4.3        Lawful Point of Discharge ........................................................................................................................... 7

5.0       STORMWATER QUALITY .................................................................................................................. 8
   5.1        State Planning Policy and Water by Design Assessment ................................................................. 8

   5.2        Construction Phase ....................................................................................................................................... 9

      5.2.1       Silt and Sediment Erosion ...................................................................................................................................... 9

   5.3        Completed Development.......................................................................................................................... 10

      5.3.1       Water Quality Objectives ..................................................................................................................................... 10

      5.3.2       Sources of Contaminants ..................................................................................................................................... 10

      5.3.3       Proposed Treatment Measures ......................................................................................................................... 12

      5.3.4       Pollutant Modelling ................................................................................................................................................ 12

6.0       STORMWATER QUANTITY ............................................................................................................ 15
   6.1        Drains Analysis ............................................................................................................................................ 15

      6.1.1       Existing Catchments .............................................................................................................................................. 16

      6.1.2       Existing Site ............................................................................................................................................................... 16

      6.1.3       Proposed Site ............................................................................................................................................................ 17

      6.1.4       Peak Flow Comparison ......................................................................................................................................... 18

      6.1.5       Peak Flow Mitigation (OSD) ............................................................................................................................... 18

   6.2        Proposed Drainage .................................................................................................................................... 22

   6.3        Downstream Infrastructure Consideration ...................................................................................... 22

7.0       FLOODING ........................................................................................................................................... 22
8.0       CONCULSION ...................................................................................................................................... 23
APPENDIX A – Detailed Site Survey ........................................................................................................ 24


SCG Consulting Engineers                                                   Page 1                                                             SCG Ref: 33132(SWMP).RevB