Swmp Rfi

Table of Contents
Executive Summary ................................................................................ 2

1.    Introduction ..................................................................................... 6
      1.1     Site Characteristics ................................................................................ 6
      1.1.    Flood Overlay ......................................................................................... 7
      1.2.    Lawful Point of Discharge .................................................................... 8
      1.3.    Request for Information ....................................................................... 9
              Item 10: Issue – Earthworks ..............................................................................9
              Item 11 9
              Item: Flood impact assessment ........................................................................9
              Item 16 / 17 ...................................................................................................... 10
              Items 18 - 20 .................................................................................................... 10
              Item 21 11
              Item 23 / 24 ...................................................................................................... 12

2.    STORMWATER QUANTITY.............................................................. 13
      2.1.    Hydrologic Assessment ...................................................................... 13
              2.1.1.        Existing Scenario .............................................................................. 13
              2.1.2.        Rational Method Check ................................................................... 14
              2.1.3.        Developed Scenario ......................................................................... 15
              2.1.4.        Mitigation Scenario.......................................................................... 17
      2.2.    Flood Investigation .............................................................................. 19
              2.2.1.        Flood Model ...................................................................................... 19
              2.2.2.        Existing Scenario (E05) .................................................................... 19
              2.2.3.        Proposed Scenario (P06)................................................................. 19
              2.2.4.        Afflux .................................................................................................. 19
              2.2.5.        Peak Flow .......................................................................................... 20
              2.2.6.        Flood Storage ................................................................................... 20
              2.2.7.        Flood Immunity ................................................................................ 21

3.    STORMWATER QUALITY ................................................................ 23
      3.1.    Design Objectives ................................................................................ 23
      3.2.    Stormwater Quality Treatment ......................................................... 23
              3.2.1.        Strategy ............................................................................................. 23
              3.2.2.        MUSIC Parameters........................................................................... 23
              3.2.3.        Catchment Areas .............................................................................. 24
              3.2.4.        MUSIC Model Layout ....................................................................... 25
      3.3.    Treatment Measures .......................................................................... 26
              3.3.1.        Bioretention System ......................................................................... 26
              3.3.2.        Sediment Forebays .......................................................................... 27
      3.4.    Results .................................................................................................. 27



23-0167SMP01-V2 | Stormwater Management Plan | 33 Pavilion Street, Pomona