Reference Document - RAL23/0013.02 - Part 2 (As Published)

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 – 8 - 20.................................................................................................... 10
              Item 21 11
              Item 23 / 24 ...................................................................................................... 12
      1.4.    Further Advice ..................................................................................... 13
              Issue - Stormwater Quality ............................................................................. 13
              Information Request........................................................................................ 14
              Detention Basin ................................................................................................ 15

2.    STORMWATER QUANTITY.............................................................. 18
      2.1.    Hydrologic Assessment ...................................................................... 18
              2.1.1.        Existing Scenario .............................................................................. 18
              2.1.2.        Rational Method Check ................................................................... 19
              2.1.3.        Developed Scenario ......................................................................... 21
              2.1.4.        Mitigation Scenario.......................................................................... 23
      2.2.    Flood Investigation .............................................................................. 25
              2.2.1.        Flood Model ...................................................................................... 25
              2.2.2.        Existing Scenario (E05) .................................................................... 25
              2.2.3.        Proposed Scenario (P06)................................................................. 25
              2.2.4.        Afflux .................................................................................................. 25
              2.2.5.        Peak Flow .......................................................................................... 26
              2.2.6.        Flood Storage ................................................................................... 26
              2.2.7.        Flood Immunity ................................................................................ 27

3.    STORMWATER QUALITY ................................................................ 29
      3.1.    Design Objectives ................................................................................ 29
      3.2.    Stormwater Quality Treatment ......................................................... 29
              3.2.1.        Strategy ............................................................................................. 29
              3.2.2.        MUSIC Parameters........................................................................... 29
              3.2.3.        Catchment Areas .............................................................................. 30
              3.2.4.        MUSIC Model Layout ....................................................................... 31



23-0167SMP01-V3 | Stormwater Management Plan | 33 Pavilion Street, Pomona