EngSWMP

                                       1 Memorial Avenue Tewantin, QLD 4565
                                                   State Planning Policy April 2016 – Water Quality
                                              Performance Outcome Criteria and Acceptable Outcomes


                  Performance outcomes                               Acceptable outcomes                                       Solution
                                                     f. identifies funding sources for the above, including
                                                     bonds, headworks charges or levies.




    Table A: Construction phase—stormwater management design objectives
    Application
    Applies to all climatic regions.


         Issue                                                                       Design Objectives
                           Temporary                  1. Design life and design storm for temporary drainage works:
Drainage Control
                           drainage                   • Disturbed area open for <12 months—1 in 2-year ARI event
                           works                      • Disturbed area open for 12–24 months—1 in 5-year ARI event
                                                      • Disturbed area open for > 24 months—1 in 10-year ARI event
                                                      2. Design capacity excludes minimum 150 mm freeboard
                                                      3. Temporary culvert crossing—minimum 1 in 1-year ARI hydraulic capacity
                           Erosion                    1. Minimise exposure of disturbed soils at any time
Erosion Control
                           control measures           2. Divert water run-off from undisturbed areas around disturbed areas
                                                      3. Determine the erosion risk rating using local rainfall erosivity, rainfall depth, soil-loss rate or
                                                      other acceptable methods
                                                      4. Implement erosion control methods corresponding to identified erosion risk rating
                           Sediment control           1. Determine appropriate sediment control measures using:
Sediment Control
                           measures                   • potential soil loss rate, or
                                                      • monthly erosivity, or
                                                      • average monthly rainfall
                                                      2. Collect and drain stormwater from disturbed soils to sediment basin for design storm event:
                                                      • design storm for sediment basin sizing is 80th% five-day event or similar