Reference Documents - MCU23 0070

         STORMWATER QUALITY

4.1      CONSTRUCTION PHASE STORMWATER QUALITY MANAGEMENT
4.1.1    INTRODUCTION

This section provides conceptual stormwater quality management strategies for construction phase.
These strategies are applicable for all stages of the development. No modelling has been undertaken
for the construction phase stormwater quality management. Detailed Erosion and Sediment Control
Plans will be prepared during detailed design phase and implemented during construction.

4.1.2    POLLUTANTS

Typical pollutants generated during the construction phase of an urban development are shown in
Table 12. These based on Table C4.1 BCC’s Subdivision & Development Guidelines Part C Section 4.1.1
(2008).

                                     Table 12 – Construction Phase Pollutants
Pollutant          Potential Source
Litter             Paper, construction packaging, food packaging, cement bags, off-cuts.
Sediment           Unprotected exposed soils and stockpiles during earthworks and building works.
Hydrocarbons Fuel/oil spills, leaks from construction equipment, and temporary car park areas.
Toxic
             Cement Slurry, asphalt primer, solvents, cleaning agents, and washwaters etc.
Materials
pH altering
             Cement slurry, acid sulfate soils, and washwaters
substances

4.1.3    WATER QUALITY OBJECTIVES

It is recommended that the amount of runoff crossing and leaving the site is kept to a minimum during
the construction phase to restrict soil erosion and mobilisation of sediments and pollutants through
and off the site. Table 13 presents an extract from Table A, Appendix 2 of the State Planning Policy
(2017) objectives for construction phase stormwater quality management

                               Table 13 – Construction Phase Performance Criteria
 Issue                 Desired Outcomes
                       1. Stage clearing and construction works to minimise the area of exposed soil
                           at any one time.
                       2. Effectively cover or stabilise exposed soils prior to predicted rainfall.
 Erosion control
                       3. Prior to completion of works for the development, and prior to removal of
                           sediment controls, all site surfaces must be effectively stabilised using
                           methods which will achieve effective short-term stabilisation.
                       1. Direct runoff from exposed site soils to sediment controls that are
                           appropriate to the extent of disturbance and level of erosion risk.
                       2. All exposed areas greater than 2500m² must be provided with sediment
 Sediment
                           controls which are designed, implemented and maintained to a standard
 Control
                           which would achieve at least 80% of the average annual runoff volume of
                           the contributing catchment treated (i.e. 80% hydrological effectiveness) to
                           50mg/L Total Suspended Solids (TSS) or less, and pH in the range (6.5–8.5).

SITE BASED STORMWATER MANAGEMENT PLAN – Revision B                              36 & 38 DUKE STREET, SUNSHINE BEACH
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