Torrens Taskforce Torrens Taskforce Summary of Findings FINAL REPORT 3 May 2007 Acknowledgements This is a report of the Torrens Taskforce to the Hon Gail Gago, Minister for Environment and Conservation. The report was produced with the assistance of the Torrens Taskforce Reference Group, the Adelaide and Mount Lofty Ranges Natural Resources Management Board staff and consultants from ARUP Pty Ltd. Torrens Taskforce - Members Professor Don Bursill, Chair, Torrens Taskforce Professor George Ganf, University of Adelaide Dr. David Cunliffe, Department of Health Dr. Michelle Bald, Department of Water, Land & Biodiversity Conservation Mr. Peter Koukourou, Central Group, Natural Resource Management Board Mr. Mike Burch, Australian Water Quality Centre Professor Hilary Winchester, University of South Australia Dr. Simon Bryars, South Australian Research & Development Institute Professor Howard Fallowfield, Flinders University Professor Simon Beecham, University of South Australia Torrens Taskforce – Reference Group Lord Mayor Michael Harbison, City of Adelaide Mayor Harold Anderson, City of Charles Sturt Councillor John Kennedy, Campbelltown City Council Mayor Bill Cooksley, Adelaide Hills Council Mr. David Duncan, Environmental Protection Authority Dr. John Howard, South Australian Water Corporation Mr. Bob Inns, Department of Environment & Heritage Ms. Carmel Schmidt, Primary Industry Resources South Australia Mr. Ben Clark, South Australia Tourism Commission Mr. John Phillips, KESAB Mr. Robert Myers, Landcare & Rural Community Conservation Groups Dr. John Cugley, Friends of the Gulf St. Vincent Mr. Jim Douglas, Western Adelaide Coastal Residents Association Mr. Rob Skipper, Torrens Lake Users Mr. Wayne Cornish, South Australian Farmers Federation Ms. Jane Corin, Conservation Council Mr. Trevor Ranford, Apple & Pear Association Mr. Michael Leyland, City of Adelaide Mr. Craig Bildstien, The Advertiser Ms. Yvonne Sneddon, Adelaide and Mount Lofty Ranges NRM Board Thanks are also extended to the various staff, consultants and Members who provided significant technical inputs. Ms. Whendee Moore, Ms. Kate Milburn and Mr. Borvin Kracman of ARUP Pty Ltd Mr. Paul Manning, Eco Management Services Mr. David Duncan, EPA Mr. Ken Schalk, Tonkin Consulting Professor Simon Beecham, University of SA Professor Howard Fallowfield, Flinders University Mr. Mike Burch, SA Water Quality Centre Dr. Stephen Gale, University of Sydney Mr. Alan Ockenden, Mr. Keith Downard, Mr. Andrew Thomas and Mr. Peter Shultz of AMLR NRM Board 3 May 2007 copyright Torrens Taskforce Summary of Findings Contents Page 1 Executive Summary 1 2 Background 6 2.1 Introduction 6 2.2 Formation of Taskforce and Reference Group 7 2.3 Terms of reference and the Taskforce 9 2.4 Conduct and activities of the Taskforce and Reference Group 9 3 Aspirational Goals / Objectives for the Torrens 11 3.1 State of the catchment and river health 11 3.2 Setting inspirational objectives 13 3.3 Iconic objective for the river 14 3.4 Environmental values 14 3.5 Specific water quality objectives 18 4 Review of Previous Work and Existing Strategies 21 4.1 TCWM Plan 2002 – 2007 / Initial NRM Plan 21 4.2 Torrens Lake algae bloom prevention strategy 24 4.3 Adelaide Coastal Waters Strategy – current 24 4.4 Contemporary research 25 5 Investigations Undertaken by Taskforce 26 5.1 Key strategies requiring investigation 26 5.2 Slowing, storing and treating urban runoff 26 5.3 WSUD – Retrofitting Water Sensitive Urban Design 27 5.4 Torrens Lake nutrient balance and treatment options 28 5.5 Audit on stormwater / non stormwater inflows 31 5.6 Gross pollutant traps and capture 32 5.7 Heavy metals in sediments 32 5.8 Environmental enhancement flow / water transfers 33 5.9 Weir at Frome Road 34 5.10 Exotic and native vegetation in the catchment 35 5.11 Highbury and other storage options 36 5.12 Roles and responsibilities 36 6 Recommendations 37 6.1 Adopting water quality objectives 37 6.2 Current management strategies to strengthen and/or accelerate 38 6.3 Environmental flows in urban rivers 40 6.4 WSUD and modifying urban stormwater flows 41 6.5 Increase attention to compliance 42 Torrens Taskforce Summary of Findings 6.6 Torrens Lake initiatives 43 6.7 Community engagement 44 6.8 Roles and responsibilities 7 Reference Documents 46 Torrens Taskforce Summary of Findings Executive Summary Preamble Media and community concern over the state of the River Torrens, specifically the Torrens Lake’s susceptibility to cyanobacterial blooms over the summer of 2005/ 2006 promoted the Government, through Minister Gago to establish a Taskforce to review the situation. With the assistance of the Adelaide and Mount Lofty Ranges Natural Resources Management Board a Torrens Taskforce was established and led by Professor Don Bursill, a local scientist and water quality management practitioner. The Taskforce had a very strong and credible scientific bias with members from all of the State’s universities and selected experts from key agencies. To help support the Taskforce’s review, a community based Reference Group was established. This was done to ensure the various reviews, technical investigations and proposed strategies were able to be embraced and supported by the community. The Reference Group comprised of representatives from local government, community groups, state government agencies, conservations organisations, industry and the media. A good balance of urban/rural interests and perspectives as well as a community/government representation was achieved. The Taskforce commenced in September 2006 to address the following terms of reference; • Consider aspirational objectives, goals and targets for the River Torrens catchment, including the Torrens Lake. • Review the previous work including relevant contemporary academic publications and the current programs and projects that have been implemented on the River Torrens and catchment as well as actions on the Torrens Lake. • Identify current and possible future issues (including cyanobacteria and the accumulation of gross pollutants) that need to be addressed with respect to the health of the urban River Torrens and Torrens Lake from an ecological, social and economic perspective. • Assess and recommend viable management and river rehabilitation options that are required to improve the River Torrens and Torrens Lake Condition and in particular to manage urban river algal blooms, litter and debris and the ecological health of the system. • Provide a report to the Minister on recommended actions and responsibilities and findings by the end of March 2007. Review of previous work The Taskforce reviewed the management programs of the Adelaide and Mount Lofty Ranges Natural Resources Management Board (and its antecedent Torrens Catchment Water Management Board) and the recent Torrens Lake Algal Bloom Management Plan Update 2005. Other recent investigations, scientific papers and reports were also collated and reviewed. Both the Taskforce and the Reference Group were impressed by the amount if work and effort invested to date. However there were some key areas that needed to be further addressed. Broadly these areas can be summarised as follows; • A greater focus on clearly articulating water quality objectives to meet the desired environmental values of the various parts of the catchment; • Acceleration of fundamental catchment management activities, particularly in the rural catchment such as fencing off watercourses to stock; Page 1 Torrens Taskforce Summary of Findings • More attention on compliance to ensure both urban and rural communities exercise their duty of care and desist from poor management practices that lead to these water quality problems. The review also confirmed the huge challenge that urban stormwater represents in terms of poor water quality from highly developed catchments. Unlike the newer urban areas to the north and south of Adelaide the Torrens urban catchment has virtually no water sensitive urban design features such as wetlands and swales, very little is left of the natural watercourse and a huge organic and chemical pollution load comes from street trees, motor vehicles, roads and a host of diffuse urban sources quickly transmitted through very efficient stormwater systems. This combined with the fact that cyanobacterial blooms in the Torrens Lake can occur even with very low nutrient (phosphorous) and organic carbon loads make the solutions to these problems extensive and expensive commitments. The Taskforce undertook a number of studies to increase understanding of particular issues and potential management strategies. These studies included nutrient balances in the Torrens Lake, water treatment options for urban stormwater and especially for the Torrens Lake, investigations of gross pollutant traps, dry weather stormwater discharges and various innovative water sensitive urban design projects. The recommendations of the Taskforce, with the support of the Reference Group, fall into three groups, namely; 1. Actions to be accelerated from the current management programs – eg. Fencing off watercourses to stock, increasing emphasis and follow up on compliance with existing regulations and policy and expanding the gross pollutant trap (GPT) facilities to cover all significant stormwater discharges, including First Creek which discharges near the Botanic Gardens. 2. Set specific water quality objectives and review and upgrade monitoring to regularly measure progress in achieving these objectives. A detailed set of water quality objectives is provided