f- ' CRES Monograph 5 V ■ / * * i . Environmental water quality ' # ■ * a systems stud^inTJggeranong Creek and Kambah Pool Tom Beer, Peter C Ypung, Robert B Humphries and James S Burgess UNCOCK )3 2 2 18 159 This book was published by ANU Press between 1965–1991. This republication is part of the digitisation project being carried out by Scholarly Information Services/Library and ANU Press. This project aims to make past scholarly works published by The Australian National University available to a global audience under its open-access policy. CRES Monograph 5 Environmental water quality a systems study inTuggeranong Creek and Kambah Pool Tom Beer, Peter C Young, Robert B Humphries and James S Burgess Centre for Resource and Environmental Studies, Australian National University, Canberra. c Centre for Resource and Environmental Studies 1982 National Library of Australia Cataloguing-in-publication entry Environmental water quality. Bibliography. ISBN 0 86740 018 8. I. Water quality - Australian Capital Territory - Tuggeranong Creek. 2. Water quality - Australian Capital Territory - Kambah Pool. I. Beer, Tom, 1947-. II. Australian National University. Centre for Resource and Environmental Studies. (Series: CRES monograph; no.5). 628.1'61 Printed and manufactured in Australia by The Australian National University Distributed by ANU Press P.O. Box 4 Canberra A.C.T. 2600. library iii PREFACE Construction of an artificial Lake Tuggeranong comprises one of the possible options for the future development of the Tuggeranong region of the Australian Capital Territory. In order to provide scientific data as a basis for planning this structure and modelling its effects upon the down­ stream Murrumbidgee, the National Capital Development Commission contracted various studies. This monograph provides an account of the Centre for Resource and Environmental Studies (CRES) contribution to one of these known as the Murrumbidgee River Water Quality Study. The raw data on which this work is based is available in a series of working papers prepared by the CRES Applied Systems group. We must, in fact, emphasise that the CRES research programme has been a complete team effort,with numerous individuals contributing in various ways. A list of CRES team personnel and their contribution is given below: Tony Bayes computer programming, field assistance Ruth Bel in illustrations Julie Cathcart secretarial, typing June Harries secretarial, typing Alan Henderson research assistance, field assistance Tony Jakeman mathematics, modelling Pat Mitchel1 computer programming, data analysis, field assistance Barbara Piper secretarial, typing Christina Sirakoff data analysis, computer programming David (Dingle) Smith hydrology, dye tracer studies Paul Steele field assistance In addition, the students enrolled in the program for the Master of Resource and Environmental Studies provided assistance with the field work.. iv CONTENTS Page Preface i i i Contents iv CHAPTER 1 INTRODUCTION 1 1.1 Inland Australian Waters 1 1.2 Aim of the Study 5 1.3 Existing Information 6 1.4 The Character of the Tuggeranong Creek Catchment 7 1.5 Morphology 10 CHAPTER 2 QUIESCENT CONDITIONS 13 2.1 The Sampling Program 13 2.1.1 Fortnightly sampling program 14 2.1.2 Daily sampling program 15 2.2 Spatial Analysis of Nutrients 18 2.2.1 Phosphorus 18 2.2.2 Nitrogen 18 2.2.3 Chlorophylla and phaeophytin 20 2.2.4 Dissolved oxygen 22 2.2.5 Turbidity 22 2.3 Nutrient Behaviour in the Retention Pond 22 2.4 Conductivity 27 2.5 Estimation of Flows from Conductivity Measurements 29 2.6 Attached Algae 31 2.7 Bacterial Contamination of Tuggeranong Creek 32 V CHAPTER 3 STORM EVENTS 41 3.1 Introduction 41 3.2 Gauging the Concrete Channel at S ite A 41 3.3 Flow-velocity Relations 42 3.4 Behaviour of the System During Storms 44 3.5 Flow-Duration-Concentration 46 3.6 The Storm of 4 January, 1980 49 3.7 Erosion in Tuggeranong Creek 52 3.8 Nutrient Loading and Land Use Characteristics 52 CHAPTER 4 KAMBAH POOL AND THE MURRUMBIDGEE 55 4.1 H is to ric a l Data 55 4.2 Longitudinal Variability 56 4.3 Biology and Water Q uality o f Kambah Pool 56 4.3.1 Survey methods and data analysis 58 4.3.2 Results and discussion 60 4.4 Diurnal Variation in Dissolved Oxygen 68 CHAPTER 5 DISPERSION AND MIXING 5.2 Tuggeranong Retention Pond 70 5.3 Tuggeranong Creek Concrete Channel 84 5.4 Downstream Tuggeranong Creek 85 5.5 Kambah Pool 87 5.6 Dispersion Modelling 91 CHAPTER 6 MATHEMATICAL MODELLING 95 6.1 A Flow Routing Model of the Murrumbidgee River 97 System Including Tuggeranong Creek 6.2 R ainfall-F low Model fo r Tuggeranong Creek 104 6.3 A Conservative Pollutant Dispersion and 119 Transportation Model vi CHAPTER 6 MATHEMATICAL MODELLING (continued) 6.4 A Partial Steady State Model for 142 Non-conservative Pollutants 6.5 Recommendations on Future Modelling Studies 149 CHAPTER 7 ESTIMATION OF NUTRIENT LOADING AND TROPHIC STATUS 153 OF LAKE TUGGERANONG 7.1 The Prediction of Phosphorus and C hlorophylla 153 Concentration in Canberra's Urban Lakes 7.2 Estimation of the Trophic Status of Lake 155 Tuggeranong 7.3 The Trophic Status of Kambah Pool: Present 159 and Future CHAPTER 8 PRINCIPAL FINDINGS 163 LIST OF ABBREVIATIONS USED IN REFERENCES 167 REFERENCES 169 vi i CONTENTS Appendices are provided on m ic ro fic h in the back of the book Page N< APPENDIX 1 ALGAL DATA 1 BATERIOLOGICAL DATA 3 APPENDIX 2 CHARACTERISATION OF LONGITUDINAL DISPERSION 1 1. Introduction 1 2. Dead Zone Processes 4 3. Problems in E stim ating the Dispersion Coefficient 7 4. D is c re te -tim e Models 11 5. The Identification and Estimation of Discrete-time Models 16 6. Comparison With the Routing Procedure 17 7. Discussion and Conclusions 2D APPENDIX 3 Listing of the water quality and flow data used in p ro je c t 32 1 1. INTRODUCTION 1.1 Inland Australian Waters Williams (1974) has suggested that inland Australian waters are different in many respects to the water bodies that have been examined in the northern hemisphere. First, discharge from rivers in Australia tends to be very variable in both the short and long term. While low flows predomin­ ate, periods of very high flow occur intermittently. High flows have a flushing effect and are associated with substantially increased suspended and solute loads. Secondly,concentrations of total dissolved solids are often higher than those reported in northern hemisphere studies. Some Australian inland lakes are hypersaline. Generally higher salinities reflect higher than nor­ mal concentrations of sodium and chloride ions. However, it has been suggested that concentration of plant nutrients such as nitrogen and phos­ phorus, are often considerably higher than levels reported in many European studies. Williams suggests that some eutrophic lakes in Europe have P04-P values as low as 0.02 mg/1, levels that are not uncommon in Australian inland waters. Thirdly, Williams suggests that a major source of energy for streams comes from fallen leaf material. In Australia this is from evergreen trees, and consequently occurs throughout the year. Many northern hemisphere situ­ ations experience seasonal variations that result from deciduous tree inputs. Finally, much of the fauna of Australian waters is endemic,with close relationships to marine life. Williams suggests that the overseas practice of using freshwater fauna to assess the extent of water pollution must first await detailed ecological studies of Australian fauna,and cannot rely on overseas research results. The changes that have occurred to the hydrologic regimes of Austral­ ian urban waterways have become of greater concern to planners, engineers and public users as urban areas have grown. Until recently, the precise nature of the changes that have occurred has been inadequately studied. The paucity of local Australian information is mentioned by Hart (1974) in his Australian Water Resources Council sponsored compilation of Australian water quality criteria. Similarly, the more recent studies by Cordery (1976a, b) reinforce Hart's conclusion. Cordery (1976b, p.3) notes that, 'very little published data are available on the quality of urban runoff in Australia. 2 The data that have been published relate only to low flow conditions and hence are not really representative of the total flow'. Considerable data are available fo r a number of urbanised streams elsewhere in the world. Both Cordery (1976b) and Duncan and Douglas (1973) have reviewed this information with respect to the Australian environment, and have attempted to summarise the changes to hydrologic regimes that are thought to accompany urbanisation. Cordery (1976b) suggests that urbanised catchment discharges at times of flood are s ig n ific a n tly increased, those floods with return p e ri­ ods of one year frequently being increased by up to three times the pre­ urbanised discharge level. Following the work of H ollis (1975) he suggests that urbanisation increased larger floods by smaller amounts and that very large floods are increased by insignificant amounts. Similar findings have been reported by Anderson (1970), da Costa (1970) and Leopold (1968). Cordery (1976b) also reports that total runoff volumes from urban­ ised catchments can be increased by up to two times. This finding is supported by Anderson (1970) and by Cordery (1976a). Considerable v a ria b il­ ity in the size of the increase occurs largely as a result of highly vari­ able urban land uses and because of the numerous physiographic variables in the urban catchments. The th ird major e ffe ct of a change from rural to urban land use is the enormous increase in sediment loads carried by the streams during the construction phase of development. Numerous studies (Bryan, 1972; Dawdy, 1967; Walling and Gregory, 1970; Wolman, 1967 and Wolman and Schick, 1967) have demonstrated that both suspended load,, and concentration of the suspend­ ed load,increase substantially in the early phases of urbanisation.