Implementing Water Sensitive Urban Design in Stormwater Management Plans Goyder Institute for Water Research Technical Report Series No. 16/7 www.goyderinstitute.org Goyder Institute for Water Research Technical Report Series ISSN: 1839-2725 The Goyder Institute for Water Research is a partnership between the South Australian Government through the Department of Environment, Water and Natural Resources, CSIRO, Flinders University, the University of Adelaide and the University of South Australia. The Institute will enhance the South Australian Government’s capacity to develop and deliver science-based policy solutions in water management. It brings together the best scientists and researchers across Australia to provide expert and independent scientific advice to inform good government water policy and identify future threats and opportunities to water security. The following Associate organisations contributed to this report: Enquires should be addressed to: Goyder Institute for Water Research Level 4, 33 King William Street Adelaide, SA, 5000 tel: 08-8236 5200 e-mail: [email protected] Citation Myers, B., Cook, S., Pezzaniti, D., Kemp, D., Newland, P., 2015, Implementing Water Sensitive Urban Design in Stormwater Management Plans, Goyder Institute for Water Research Technical Report Series No. 16/x, Adelaide, South Australia. Copyright © 2016 University of South Australia. To the extent permitted by law, all rights are reserved and no part of this publication covered by copyright may be reproduced or copied in any form or by any means except with the written permission of the University of South Australia. Disclaimer The Participants advise that the information contained in this publication comprises general statements based on scientific research and does not warrant or represent the completeness of any information or material in this publication. Contents Contents i Figures vi Tables vii Abbreviations x Executive summary xi Part I Introduction and Background i 1 Introduction and Background 2 1.1 Introduction ........................................................................................................................ 2 1.2 Background ......................................................................................................................... 2 1.3 References .......................................................................................................................... 4 Part II Review of Stormwater Management Plans 7 2 Review of Stormwater Management Plans 8 2.1 Background ......................................................................................................................... 8 2.2 Methodology ...................................................................................................................... 9 2.3 Synopsis of Review Findings ............................................................................................. 13 2.4 Discussion of Review Findings .......................................................................................... 19 2.4.1 Setting WSUD Objectives .................................................................................... 20 2.4.2 Assessing Water Quality and Volume Management by WSUD........................... 22 2.4.3 Limited Assessment of Stormwater Peak Flow Management and Stream Flows 22 2.4.4 Limited Attention to Policy Based Measures ...................................................... 23 2.4.5 Costing and Prioritisation .................................................................................... 23 2.4.6 Ability to Implement SMP Outcomes .................................................................. 24 2.5 Summary ........................................................................................................................... 25 2.6 References ........................................................................................................................ 26 Part III Hydrological Assessment of Storage Based WSUD Systems for Quantity Management 29 3 Hydrological Assessment of Storage Based WSUD Systems for Quantity Management 30 Implementing Water Sensitive Urban Design in Stormwater Management Plans| i 3.1 Introduction ...................................................................................................................... 30 3.2 Background ....................................................................................................................... 30 3.3 Methodology .................................................................................................................... 31 3.3.1 Identification of Design Storm Events ................................................................. 31 3.3.2 Evaluating Peak Flow and Runoff Volume Estimation Using Design Storms and Equivalent Observed Storms with Antecedent Conditions .............................................. 33 3.4 Results 37 3.4.1 Identification of Design Storm Events in the Adelaide (Kent Town) rainfall record 37 3.4.2 Comparison of a Design Storm or an Equivalent Observed Storm to Predict Catchment Peak Flow and Runoff Volume ....................................................................... 39 3.4.3 Evaluating the Effect of Antecedent Conditions on WSUD system performance ..................................................................................................................... 42 3.5 Discussion ......................................................................................................................... 46 3.6 Summary ........................................................................................................................... 48 3.7 References ........................................................................................................................ 49 Part IV Assessing Water Quality Improvement: MUSIC Modelling Recommendations for South Australia 53 4 Assessing Water Quality Improvement: MUSIC Modelling Recommendations for South Australia 54 4.1 Introduction ...................................................................................................................... 54 4.2 Background ....................................................................................................................... 55 4.3 Methodology .................................................................................................................... 55 4.4 Results and Recommendations for MUSIC Simulation in South Australia ....................... 57 4.4.1 Select Meteorological Data ................................................................................. 57 4.4.2 Select Rainfall and Potential Evapotranspiration Data Time Step ...................... 57 4.4.3 Select Rainfall and PET Data ................................................................................ 58 4.4.4 Define Source Node Data .................................................................................... 65 4.4.5 Define Reuse Demand for Harvested Stormwater .............................................. 65 4.4.6 Define Catchment Area ....................................................................................... 68 4.4.7 Select Catchment Size and Percentage Imperviousness ..................................... 72 4.4.8 Select Rainfall-Runoff Parameters for the Catchment and Soil Properties ........ 78 4.4.9 Input Pollutant Data and Pollutant Generation Properties ................................ 82 Page ii of 234 4.4.10 Position relevant drainage Links, Select Link Routing and Input Link Routing Properties ......................................................................................................................... 87 4.4.11 Run Simulation .................................................................................................... 88 4.4.12 Compare Results with Water Quality Objectives ................................................ 89 4.4.13 Select Stormwater Quality Improvement Measures .......................................... 91 4.4.14 Develop treatment train ...................................................................................... 92 4.5 Discussion ......................................................................................................................... 93 4.6 Summary ........................................................................................................................... 95 4.7 References ........................................................................................................................ 95 Part V Flow Regime Assessment for Waterway Protection 99 5 Flow Regime Assessment for Waterway Protection 100 5.1 Introduction .................................................................................................................... 100 5.2 Background ..................................................................................................................... 101 5.3 Stream Flow Management in Greater Adelaide ............................................................. 102 5.4 Stream Flow Analysis ...................................................................................................... 104 5.4.1 Spell Duration Frequency .................................................................................. 107 5.4.2 Channel Forming Flows ..................................................................................... 109 5.5 Recommendations .........................................................................................................