An Environmental Analysis of Germiston Lake and Immediate Environs with Specific Reference to Water Quality
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An environmental analysis of Germiston Lake and immediate environs with specific reference to water quality. By HILDA HOLDER Mini-thesis Submitted in fulfillment Of the requirements of the degree MAGISTER SCIENTIAE In GEOGRAPHY In the FACULTY OF SCIENCE At the RAND AFRIKAANS UNIVERSITY Supervisor: Dr. J. M. Meeuwis. Co- Supervisor: Dr. H. H. du Preez (Rand Water). August 1999 Acknowledgements. The completion of the present work would not have been possible without the help of the following people: Dr. H. du Preez and Dr. J. Meeuwis for their assistance, motivation, guidance and patience throughout the course of this study, My parents for their help and support, The Department of Geography and Environmental Management and the Department of Zoology at the Rand Afrikaans University for the use of facilities, Roelf Van Loggenberg and Zandile Khati for data and useful discussions on the study sites, Department of Chemistry, Rand Afrikaans University and Rand Water for analyzing water samples, All the post-graduate students at R.A.U. for their guidance and support throughout the study, Mr. K. Edwards for the use of his computer, Miss S. Holder for her help with the technical completion of the thesis. ABSTRACT. Victoria Lake also known as Germiston Lake is an urban impoundment which is situated east of Johannesburg. This Lake is used for a number of recreational activities and can be viewed as an important feature of this area. It is a natural perennial pan and has several inlets (inflows) which drain a part of Germiston's business area and surrounding residential areas. In the past various studies have focused on the water quality as well as other aspects of the ecology of the Lake that may influence recreational activities and the physical-chemical quality of the water. However, information on the physical-chemical quality of the inflow water is poorly investigated and needs further attention. This study gathered further data on the water quality and associated problems within the major inlets to the Lake. Six inlets were monitored monthly for a year. The water samples that have been collected were analyzed for several physical and chemical constituents. In general it seemed as if the waters of the inlets around Victoria Lake were more polluted in comparison to the surface waters of the lake Sites 1, 4 and 5 seemed to be the most polluted inlets and it should be closely monitored in future. Most of the water quality constituents that have been compared with the water quality criteria exceeded the acute effect values given by the South African Water Quality Guidelines. Waste is thus continually dumped into the Victoria Lake via the major inlets resulting in water pollution. The quality of this resource is therefore diminishing rapidly. If Victoria Lake is to be successfully used and managed in order to limit the impact on the environment, all further development and management should take place in terms of sustainable development. Opsomming. Victoria Meer, ook bekend as Germiston Meer is 'n meer wat oos vanaf Johannesburg gelee is. Hierdie meer word vir verskeie ontspanings aktiwiteite gebruik en kan beskou word as 'n belangrike besienswaardigheid van die area. Dit is 'n natuurlike standhoudende pan wat verskeie inlate besit tot die meer. Hierdie inlate dreineer 'n groot deel van Germiston se besigheid area asook omliggende residensiele dele. Verskeie studies het in die verlede gefokus op die water kwaliteit van die meer asook verskeie ekologiese aspekte van die meer en die invloed daarvan op ontspaninngsaktiviteite wat by die meer aangebied word. Die fisiese-chemiese water kwaliteit van die inlate tot die meer was egter swak ondersoek en moet verder aandag geniet. Hierdie studie het verdere inligting oor die water kwaliteit en probleme met betrekking tot die inlate tot die meer ingesamel. Ses inlate was maandeliks vir 'n jaar . gemoniteer . Die water monsters wat versamel was, is vir verskeie fisiese en chemiese komponente geanaliseer. Oor die algemeen het dit geblyk dat die water van die inlope veel meer besoedel was as die oppervlak water van Victoria Meer. Dit het geblyk dat terrein 1, 4 en 5 die mees besoedelste was en dat hierdie inlate in die toekoms nouliks gemonitor moet word. Meeste van die water kwaliteitskomponente wat met die Suid Afrikaanse water kwaliteits kriteria vergelyk was het die akute effek waarde oorskrei. Afval word dus aanhoudend deur die inlope tot die meer, in die meer gestort. Die kwaliteit en algemene toestant van die meer is dus aan die kwein. As Victoria Meer suksesvol gebruik en bestuur wil word, moet toekomstige ontwikkeling en bestuur onderhoubaar plaasvind. Table of Contents: Introduction 1 Statement of problem and main objectives 2 The Study area 3.1 Location 4 3.2 Water quality and biological changes of Victoria Lake 10 3.3 Factors that could influence the water quality of Victoria lake and its inlets 14 3.3.1 Geology of the catchment area 14 3.3.2 Proposed developments at Victoria Lake 15 Basic terminology and concepts associated with water quality 16 4.1 Water pollution 16 4.2 Water quality 19 4.2.1 Water quality constituents 20 4.2.2 Water quality guidelines 35 Data collection and analysis 41 5.1 Shortcommings of data 43 Results and discussion 46 Conclusion 81 Synthesis and recommendations 82 8.1 Urban impoundment management 91 References 94 10.Appendix 100 10.1 Appendix1 100 10.2 Appendix 2 104 10.3 Appendix 3 106 10.4 Appendix 4 109 ' 10.5 Appendix 5 121 1. INTRODUCTION. Local authorities provide urban impoundments (e.g. lakes, dams, etc.) primarily for recreation and storm-water control, as well as for a psychological escape for city dwellers from the pressures of modem urban life. In addition, urban water bodies are increasingly being developed because they enhance the value of the real estate, houses, office blocks and commercial developments in their immediate vicinity (Wiechers, et al., 1997). Unfortunately, urban impoundments are fed predominantly by storm-water runoff from the urban catchments in which they are situated. Urban runoff is usually polluted owing to industrial activities, urban-runoff and oil pollution. Impoundments thus serve as reservoirs, which intercept this pollution, and the net effect can be: a silted-up impoundment highly polluted water eutrophication and the associated growth of undesirable algae and water weeds health risks due to fecal pollution, and aesthetic problems such as unsightly algae, floating debris and malodours. The complex nature of water sources for urban impoundments typically results in the occurrence of a combination of the above problems. (Wiechers, et al., 1997). Victoria Lake also known as Germiston Lake is one of these urban impoundments, which is situated to the east of Johannesburg. This Lake is used for a number of recreational activities and can be viewed as an important feature of this area as water skiing, bird watching, fishing and playing golf are a few of the activities that the public can participate in (Parks and grounds, 1995; Saunders, 1997; Schoonbee, et al., 1995; Vermaak, 1973; Vermaak, 1978; Wiechers,et 41996). Victoria Lake is a natural perennial pan and it has several inlets (inflows), which drain a part of the urban area of Germiston (Parks and grounds, 1995; Saunders, 1997; Schoonbee, et al., 1995; Vermaak, 1973; Vermaak, 1978; Wiechers, et al., 1996). It is important to examine the inlets of the lake as they provide the natural pathways for pollution to enter the lake and this will ultimately influence the water quality of the lake. This study will only focus on the water quality of the inlets. Because Victoria Lake is of great recreational importance various studies in the past have focused on the water quality as well as other aspects of the ecology of the Lake that may influence recreational activities. However, information on the physical-chemical quality of inflow water is poorly investigated with only a pilot study done by du Preez (1997). The results of this study suggested that the water quality was not acceptable for maintaining a healthy aquatic environment. This poor water quality can result in a public asset becoming a liability, and more seriously a health risk (du Preez, 1997; Wiechers, et al., 1996).This study will try to gather further data on the water quality and associated problems within the inlets to the lake. This data will then be evaluated according to the South African Water Quality Guidelines for recreational use and the aquatic environment. The concept of water quality in the lake can be problematic as the actual water quality in the lake is influenced by the water quality of the major inlets (Wiechers, et al., 1996). Therefore it is important to control the water quality of the major inlets in order to prevent further deterioration of the water quality in the lake and to manage the water quality sustainable. This project is also important because it contains both ecological as well as socio-cultural elements, as it is an attempt to maintain the aquatic environment within the Lake and to preserve Victoria Lake as a recreational area. 2. STATEMANT OF THE PROBLEM AND MAIN OBJECTIVES. Regular investigations have been conducted into the water quality conditions within Victoria Lake and recent reports confirm the recovery of the Lake from mine pollution (Parks and grounds, 1995; Saunders, 1997; Schoonbee, et al., 1995). Managing the water quality within the Lake is, however, not enough. What ultimately results in an urban 2 impoundment in terms of water quality related issues is chiefly the result of processes and activities taking place upstream of the lake as well as the inlets. The cycle of contamination of water systems starts with pollution generation. This could, for example, include effluent from a factory, fertilizer wash off, or diffuse pollution loads from an unserviced township area.