An Environmental Analysis of Germiston Lake and Immediate Environs with Specific Reference to Water Quality

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. After generation, a contaminant is transported into the receiving stream. This could be via pipe, or by diffuse seepage from a large area. Once in the receiving stream, the contaminant flows within the stream until it enters the impoundment. It is therefore necessary to follow an integrated approach to urban impoundment management. This approach considers catchment management, pre- impoundment management, and in-lake control (Wiechers, et al., 1997). This study will focus on pre-impoundment management in other words the management of the inlets.

The reason why it is important to monitor the major inlets to Victoria Lake is because: the inlets drain an industrial area (see appendix 1) the inlets drain a mining area (Simmer & Jack Gold Mine) the inlets have been subjected to illegal dumping (du Preez, 1997); and the inlets also drain a large part of the urban area of Germiston. It is therefore absolutely necessary to undertake an environmental assessment of the water quality of the inlets of Victoria Lake in order to preserve it as a recreational area and to maintain the aquatic environment.

The main objectives of this study are therefore: 1. To ensure suitable water quality of Victoria Lake for its various uses, by: Determining the water quality of the inlets to Victoria Lake. Examining the various water quality constituents for the water of these inlets. Evaluating the data gathered on the water quality, according to the South African Water Quality Guidelines for Recreational Use and the Aquatic Environment; and 2. To contribute to the preservation of the Victoria Lake as a recreational area, by: a) Making recommendations to mitigate the adverse aspects on the water quality.

3 3.THE STUDY AREA.

3.1 Location.

The Germiston, or Victoria Lake, near Johannesburg is a natural pan that is situated in the headwaters of the Elsburgspruit system, which falls within the boundaries of the Vaal River catchment area (figure 1). It is a small urban lake that covers a total water surface area of 58-59 ha when full. The lake has a maximum capacity of 1 525 000 cubic meters of water, and has a comparatively small natural catchment area of 1174 ha. This Lake is perennial as it has several inflows (inlets), to the Lake, which drains a part of the urban area (figures 2& 3). A weir, constructed in the late 1960's, stabilizes the water level of the lake, which is fed by a spring on its western side (Parks and grounds, 1995). (Saunders, 1997; Schoonbee, et al., 1995; Vermaak, 1973; Vermaak, 1978; Wiechers, et al. 1996). feature of this area (Parks and grounds, 1995; Saunders, 1997; Wiechers, et al. 1996).

Table 1. The Land uses in the immediate catchment area of the lake and the impoundment uses (Wiechers, et al., 1996).

Local catchment type(%) Main Uses of . :impoundment (in order of importance). Light industrial =30% Recreational (water based) Low density and high sosio-economic Recreational (waterside based) resedential area =20% Heavy industrial =15% Storm-water control Parkland \ Veld =15% Airport =10% Commercial =10%

The land use in the immediate catchment area of the lake is mixed. Forty-five percent of the catchment area is occupied by light-and heavy industrial areas while twenty percent 128'10'E

ELSBURG DAM

26'14'S- GERMISTON LAKE

Industrial Area

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Figure 1. The Elsburgspruit system, showing the location of Victoria Lake (Schoonbee, et al., 1995).

5 aL, Figure 2.Thenumberofstorm waterdrainsandotherinflowsintotheVictoria Lake(Schoonbee. 1995).

Samp ling locality et 6

Figure 3. Inlet to Lake Victoria, site 1 (refer fig. 2). A indicates site of water collection.

Figure 4. Inlet to Victoria Lake, Site 2 ( refer to fig. 2). B indicates site of water collection.

7 Figure 5. Inlet to Victoria Lake, Site 3 ( refer to fig. 2). C indicates site of water collection. r;`wr

•

Figure 6. Inlet to Victoria Lake, Site 4 and site 5 ( refer to fig. 2). D and E indicates sites of water collection.

8 Figure 7. Inlet to Victoria Lake, Site 5 ( refer to fig. 2), further down from water collection site showing various pollution in stream.

10 {I ' UUTIMIffilffi .7, !qr.

- • •

• - - • -•-••

- - • •

Figure 8. Outlet to Victoria Lake, Site 6 ( refer to fig. 2). F indicates site of water collection.

9 of the region is occupied by residential areas. Commercial land and an airport each occupy approximately ten percent of the catchment area (table 1). Victoria Lake with its established tree-line and picnic area, leisure facilities such as a golf course, Victoria Lake Club, Germiston 5 th Sea Scouts, Rondebult Bird Sanctuary and the Germiston Aquatic Club, is used for a number of recreational activities and can be viewed as an important feature of this area (Parks and grounds, 1995, Saunders, 1997, Wiechers, et al.,1996).

3.2 Water quality and biological changes of Victoria Lake

Victoria Lake has been severely polluted for decades by mine- and industrial effluents as well as seepage waters. Inflow of acid mine drainage and sludge from mines into the lake resulted in a drastic reduction in the pH, which was as low as 4.5 in 1960. As a result, it was devoid of fish life for more than 40 years prior to 1970. Owing to the absence of predators, one of the species that did survive and indeed proliferate, was the Chironomid midge, whose flying adults became problematic. This gnat plague was eventually controlled by the introduction of the several fish species into the lake when the water quality was restored (Munisipale & openbare dienste, 1992; Parks and grounds, 1995; Saunders, 1997; Schoonbee, et al., 1995; Vermaak, 1973, Vermaak, 1978).

The accumulation of sludge in the Victoria Lake has been a problem for many years due to gold mining in this area. Extensive dredging projects have been implemented during various intervals to address the sludge problem, between 1948-1972 (Vermaak, 1978). Approximately, 23 000 tons of sludge were moved from the shallow part of the Lake to the deeper parts of the Lake. Further dredging was abandoned owing to the high costs involved (Vermaak, 1978). Sludge is still a problem at Victoria Lake and it is possible that this sludge may still enter the Lake via the inlets (Du Preez, 1997).

The water in the lake was gradually neutralized between 1969 and 1970 by the addition of more than 10 64 700 liters of sodium hydroxide and about 58 968 kilograms of agricultural lime (NaOH) (Schoonbee, et al., 1995; Vermaak, 1973, Vermaak, 1978).

10 The further elimination of the major sources of pollution between 1968-1975 has led to a rapid recovery of water quality in the lake (Schoonbee, et al., 1995). Contaminated streams were diverted from the lake, and dissolved salts in the lake were found to be progressively reduced over the years (Schoonbee, et al., 1995). This recovery of the water quality conditions made it possible to reintroduce fish such as black bass, common carp, catfish and species of tilapia into the lake (Parks and grounds, 1995).

Following the recovery, submerged aquatic weeds invaded the lake. In an attempt to control the growth of these weeds, the Chinese grass carp, Ctenophryngodon idella, was introduced to the lake. The Chinese grass carp is known for its tolerance of cold water and its herbivore preference. The result was that the weed population drastically reduced (Schoonbee, et al., 1995).

Regular investigations into the water quality conditions within the Victoria Lake have been conducted and the recovery of the Lake from mine pollution was complete (Schoonbee, et al., 1995). Although the mine dumps on the south-western side of the lake have been removed, some industries still contribute to the occasional pollution of the lake water via inlets as well as storm-water drainage and runoff from roads. Tables 2 - 4 shows the improvement in the physical, chemical and bacterial conditions in the water of Victoria Lake over the years. Elevated levels of iron, zinc, copper, lead, chromium, manganese, and cadmium (table 3) have been detected in the Lake during investigations (1989-1997), which can largely be attributed to effluents and seepage waters from mines and industries in the greater Germiston business area. Values for the pH of the lake water during this period remained alkaline and conductivity, reflecting the amount of dissolved salts in the water, remained below 368011S/cm. Dissolved oxygen concentrations remained generally high. Values for total hardness and sulfate, nitrate and phosphate still reflected moderate loads of these nutrients in the lake (see table 2), (Saunders, 1997; Schoonbee, et al., 1995). Fairly high numbers of coliforms were detected during 1996 in

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13 the Lake (table 4), which could cause noticeable gastrointestinal health effects in the swimmer and bather population (South African Water Quality Guidelines (Volume 2), 1996).

A consultant was appointed to design a silt and litter trap to filter storm-water pollution, although the existing natural reed belt acts as a filtration device to some extent (Munisipale & openbare dienste, 1992; Parks and grounds, 1995; Saunders, 1997; Schoonbee, et al., 1995).

It is apparent from the above information that although the chemical and physical conditions of the water in Victoria Lake have improved, the water quality as such, will deteriorate again if the inlet water quality is not properly managed.

3.3 Factors that could influence the water quality of Victoria Lake and its inlets.

3.3.1 Geology of the catchment area of Victoria Lake.

The catchment area of Victoria Lake lies on the Turfontein Subgroup of the Central Rand of the Witwatersrand Subgroup. The geology of the catchment area is relatively consisting predominantly of the Witwatersrand gold deposits, quartzite, conglomerate and sandy shale: Gold deposists. Pyrite (FeS2) is the most conspicuous ore mineral in the Witwatersrand gold deposits, and it typically occurs in the matrix of the conglomerate as well as in the quartzite rocks above and below. Biotite, iron-rich chlorite and quartz are the most common silicate inclusions in allogenic detrital pyrite, but nickel and cobalt have also been found in these ores. The Witwatersrand gold reefs also contain cadmium, copper, nickel, manganese, lead and zinc. Quartzite. This is composed almost entirely of quartz, which contains only traces of other elements. Quartzite is siliceous sandstone that is quite hard and is very resistant

14 to weathering. It may contain feldspar and mica, such as biotite. This latter mineral is composed of potassium, silicon, aluminum and magnesium, which may be replaced by ferrous or ferric iron. Mica can also contain zinc. ❑ Conglomerates. These are coarse-grained rocks that have a variety of different particle sizes, which are often set in a finer grained matrix. Conglomerates consist of almost any hard rock and as they are deposited from fast-moving water, they are formed on the riverbeds. o Shale. These rocks consist of a mixture of clay minerals together with detrital quartz, feldspar and mica, and are very fine-grained rocks that split easily along bedding planes. These rocks tend to have higher metal concentrations than the sandstone and carbonate rocks (Saunders, 1997).

The geology of the catchment area is important because once rainwater has made contact with the earth, it percolates through the soils and rocks, or flows over the land surface, dissolving further inorganic salts as it goes. The variety and the concentrations of the salts in a stream of water reflect the character of the soils and rocks, and of the subsurface geology with which the water was in contact (Dallas & Day, 1993; Ellis, 1989; Hellawell, 1986; South African Water Quality Guidelines (Volume 2 &7), 1996).

3.3.2 Proposed developments at Victoria Lake.

Victoria Lake may form the focal point of a new development in Germiston (De Souza, 1995; De Villiers, 1993; Parks and grounds, 1995; SA Builder, 1995). The project involves improving the environmental and aesthetic quality of the lake area, as well as the image of Germiston. The Germiston Development Foundation, in partnership with the Stocks Group by the registration of a non-profit Section 21 company, proposed a three- dimensional plan for the greater Germiston area comprising: the creation of a multi-use Victoria Lake precinct; mobilization of resources for affordable housing in the greater Germiston area as part of a project called "Homes for South Africa"; and the revitalization and redevelopment of the Germiston CBD.

15 The project proposes that a 400-bedroom and suite resort hotel as well as a lakeside entertainment and leisure area will be situated on the southern shore of the lake. The hotel will link to a new retail mall. This mall will rise to four stories at the lake level, tapering to two stories further along its southern axis. The shopping mall will in turn link into twin office towers. At Rand Airport a new terminal building and concourse will be linked to the mall via a shopping bridge over Rand Airport Road. Germiston golf club on the southern tip of the Lake will be more closely integrated with the new retail and entertainment node, while up-market and middle-market residential development is planned for several nodes near the lake. (De Souza, 1995; De Villiers, 1993; Parks and grounds, 1995; SA Builder, 1995).

The main effect with engineering and construction relates to physical disturbances of the water quality (Barton, 1977; Taylor & Roff, 1986, Victor & Ogbeibu, 1986). The major effects are usually associated with an increase in suspended solids and deposited sediments. This may have an effect on the biota in the receiving water (see total dissolved solids section 4.2.1). The severity of the effect, both short and long term, however, depends on the control measures employed during construction. The effects are complex and depend on temporal (time during and after construction), spatial (distance of the lake reach disturbed), and ecological factors such as the sensitivity of the biota (Dallas & Day, 1993).

4.BASIC TERMINOLOGY AND CONCEPTS ASSOCIATED WITH WATER QUALITY.

4.1 Waterpollution.

Wisdom (1956) and Dallas & Day (1993) defined surface water pollution as "the addition of something to which changes its natural qualities so that the riparian owner does not get the natural water of the stream transmitted to him". Buckminster Fuller said: " There is no such thing as pollution. It is merely a problem of having valuable chemicals in the wrong

16 Table 5. Major water pollutants (Miller, 1991).

Pollutant Sources Effects Control Methods

Radioactive Natural sources (rocks and Cancer; genetic defects Ban or reduce use of substances soils); uranium mining and (see Section 3-2) nuclear power plants and processing; nuclear power weapons testing: more generation; nuclear strict control over weapons testing processing. shipping, and use of nuclear fuels and wastes (see Section 16-2) Heat Cooling water from Decreases solubility of Decrease energy use and industrial and electric oxygen in water; can kill waste; return heated water power plants some fish: increases to ponds or canals or susceptibility of some transfer waste heat to the aquatic organisms to air: use to heat homes. parasites, disease, and buildings. and chemical toxins; changes greenhouses composition of and disrupts aquatic ecosystems

Organic chemicals

Oil and grease Machine and automobile Potential disruption of Strictly regulate oil drilling. wastes: pipeline breaks: ecosystems: economic. transportation, and offshore oil well blowouts: recreational, and aesthetic storage: collect and natural ocean seepages: damage to coasts, fish, reprocess oil and grease tanker spills and cleaning and waterfowl; taste and from service stations and operation odor problems industry; develop means to contain and mop up spills

Pesticides and Agriculture; forestry; Toxic or harmful to some Reduce use: ban harmful herbicides mosquito control fish. shellfish. predatory chemicals: switch to birds, and mammals: biological and ecological concentrates in human fat; control of insects (Section some compounds toxic to 21.5) humans: possible birth and genetic defects and cancer (see Section 6-4) Plastics Homes and industries Kills fish: effects mostly Ban dumping. encourage unknown recycling of plastics. reduce use in packaging Detergents Homes and industries Encourages growth of Ban use of phosphate (phosphates) algae and aquatic weeds: detergents in crucial areas: kills fish and causes foul treat wastewater (see odors as dissolved oxygen Section 19.5) is depleted Chlorine Water disinfection with Sometimes fatal to Treat wastewater. use compounds chlorine: paper and other plankton and fish; foul ozone for disinfection and industries (bleaching) tastes and odors: possible activated charcoal to cancer in humans remove synthetic organic compounds

17 Table 6. Major water pollutants (continue) (Miller, 1991).

Pollutant Sources Effects Control Methods

Oxygen- Natural runoff from land; Decomposition by oxygen- Treat wastewater; minimize demanding human sewage; animal consuming bacteria agricultural runoff wastes wastes; decaying plant life; depletes dissolved oxygen industrial wastes (from oil in water; fish die or migrate refineries. paper mills, food away; plant life destroyed; processing. etc.); urban lout odors; poisoned storm runoff livestock Disease-causing Domestic sewage; animal Outbreaks of waterborne Treat wastewater: minimize agents wastes diseaseS, such as typhoid, agricultural runoff; infectious hepatitis. establish a dual water cholera, and dysentery; supply and waste disposal infected livestock system Inorganic chemicals and minerals

Acids Mine drainage; industrial Kills some organisms; Seal mines; treat wastes; acid deposition increases solubility of wastewater; reduce (Section 18.2) some harmful minerals atmospheric emissions of sulfur and nitrogen oxides (Section 18-7)

Salts Natural runoff from land; Kills freshwater organisms; Treat wastewater; reclaim irrigation; mining; industrial causes salinity buildup in mined land: use drip wastes; oil fields; urban soil; makes water unfit for irrigation; ban brine storm runoff; deicing of domestic use, irrigation. effluents from oil fields roads with salts and many industrial uses

Lead Leaded gasoline; some Toxic to many organisms. Ban leaded gasoline and pesticides; smelting of lead including humans pesticides; treat (see Section 20-5) wastewater Mercury Natural evaporation and Highly toxic to humans Treat wastewater; ban dissolving: industrial (especially methyl unessential uses (Section wastes; fungicides mercury) 20.5) Plant nutrients Natural runoff from land: Algal blooms and Advanced treatment of (phosphates and agricultural runoff; mining: excessive aquatic groWth; industrial, domestic, and nitrates) domestic sewage; kills fish and upsets food-processing wastes: industrial wastes; aquatic ecosystems: recycle sewage and animal inadequate wastewater eutrophication; possibly wastes to land; minimize treatment; food-processing toxic to infants and soil erosion industries: phosphates in livestock: foul odors detergents Sediments Natural erosion, poor soil Major source of pollution More extensive soil conservation; runoff from (700 times solid sewage conservation practices agricultural, mining. discharge); fills in (Section 9-4) forestry, and construction waterways, harbors, and activities reservoirs; reduces shellfish and fish populations: reduces ability of water to assimilate oxygen-demanding wastes

IS place at the wrong time". Dr. Arthur Key has said that: "A river is polluted when the water in it is altered in composition or condition, directly as a result of the activities of man, so that it becomes less suitable in its natural state". Ellis (1989) stated " the alteration in composition or condition of surface water, either directly or indirectly as the result of the activities of man, which initiates modifications of ecological systems, hazards to human health and renders the stream less acceptable to downstream users (see table 5 and 6). If this definition is employed, surface water pollution can then be divided into nine possible sections: thermal pollution the addition of pathogenic organisms, creating a public health hazard oil pollution the addition of readily biodegradable organic material that will in the depletion or complete removal of dissolved . oxygen the addition of inert, insoluble mineral material toxicity due to the presence of a) synthetic organic compounds and b) salts of heavy metals enhanced eutrophication acid deposition or discharges radioactivity (Ellis, 1989).

There are two sources of water pollution (see figure 9): The first are point pollutant sources, where the pollutant discharges from known discrete sources, such as effluent from industry. The volume and the quantity can usually be measured and quantified. Non-point pollutants from surface run-off, infiltration or atmospheric sources. These sources cannot be pin pointed to any one particular place (Miller, 1991).

4.2 Water Quality.

Water quality is the value or usefulness of water, determined by the combined effects of its physical attributes and its chemical constituents, varying from user to user (Dallas &

19 Day, 1993). The South African Water Quality Guidelines (Volume 7, 1996) define the term water quality as the physical, chemical, biological and aesthetic properties of water that determine its fitness for a variety of uses and for the projection of the health and

City Rural homes

Cropland Suburban development Nonpoint Animal feedlot

Sources'`zz.,

Sewage treatment plant

Point Sources Factory

Figure 9. Point and non - point pollution (Miller, 1991).

integrity of aquatic ecosystems. Many of these properties are controlled or influenced by constituents that are either dissolved or suspended in water.

4.2.1 Water quality constituents.

The term constituent is generally used for any of the properties of water and/or the substances suspended or dissolved in it. Another term used for constituent is water quality variable. The following constituents have been use in this study:

20 1. Physical constituents.

Temperature: Temperature plays an important role in water by effecting the rates of chemical reactions and therefore also the metabolic rates of organisms. The toxicity of most substances and the vulnerability of organisms to these substances are intensified as water temperature increases. Temperature may also act acutely, that is directly, whenever lethal limits are exceeded (Dallas & Day, 1993; Ellis, 1989; Hellawell, 1986; South African Water Quality Guidelines (Volume 2 &7), 1996).

Floating matter/ refuse: Human activities frequently result in the presence of floating matter and refuse in the aquatic environment. Waste oil, grease, plastic containers and bags, bottles, cans, containers and domestic refuse lead to aesthetically unattractive recreational waters. Submerged refuse also represents a danger to recreational water users. However natural processes can also contribute to this phenomenon. Decaying vegetation and other organic substances in an advance state of decomposition in water release fatty and oily byproducts which produce an oily sheen and often cause objectionable odours (Dallas & Day, 1993; Ellis, 1989; Hellawell, 1986; South African Water Quality Guidelines (Volume 2 &7), 1996).

Odour: Odours associated with recreational water detract from aesthetic appreciation of water bodies and are perceived to indicate the presents of pollutants. Odour can indicate varied instances of pollution or imbalance in natural ecosystems, and can therefore be linked to a wide range of factors. These include the presence of excess algae or aquatic plants, excess nutrients, low dissolved oxygen, extremes of pH or temperature, discharges of sewage or other wastes, chemical discharge and refuse (South African Water Quality Guidelines (Volume 2 &7), 1996).

21 Clarity and colour: Clarity refers to the depth to which light can penetrate in a water body. Lack of clarity is frequently associated with turbidity. Turbidity is a measure of suspended material, such as clay, sand, silt, and finely divided organic matter, plankton and other micro-organics. Water become highly turbid and laden with suspended matter in the rainy season. This load of suspended matter becomes trapped within the Lake, at great economic cost. Turbidity reduces temperature and light penetration in extreme cases. Clarity and turbidity together pose a danger for swimming since potentially hazardous objects and shallow bottoms may be obscured (Dallas & Day, 1993; South African Water Quality Guidelines (Volume 2), 1996).

The acceptability of colour in recreational water is extremely subjective. To be aesthetically attractive, water should be virtually free from substances, which produce "non-natural" colour (South African Water Quality Guidelines (Volume 2), 1996).

pH: In natural waters, pH is a measure of the acid-base equilibrium achieved by dissolved components, salts and gasses (Hellawell, 1986; South African Water Quality Guidelines (Volume 2 &7), 1996). Dallas & Day, 1993, defines pH as the negative logi 0 of the hydrogen ion in activity: a measure of acidity (pH<7) or alkaline condition (pH>7). Alkalinity is largely determined by the concentration of hydroxyl ions, (Off); bicarbonate ions (HCO3); and carbonate ions (C03 2-). pH is largely determined by the concentration of hydrogen ions, (H +).

These ions [the concentration of hydroxyl ions, (OFF); bicarbonate ions (HCO3); and carbonate ions (C03 2-) and hydrogen ions, (H+)] are in dynamic equilibrium in most water samples, and a change in the concentration of any one will have an effect on all of the others. Addition of an acid or alkli to a water body will alter the pH. Since pH is a log scale, a change of one unit means a ten fold change in [r]. Further, in poorly buffered waters pH can change rapidly. Most fresh waters in South Africa are relatively well

22 buffered and more or less neutral, with pH ranges around 6-8 (Dallas & Day, 1993; Ellis, 1989; Hellawell, 1986; South African Water Quality Guidelines (Volume 2 &7), 1996).

The pH of natural waters are determined by both geological and atmospheric influences. Human induced acidification of rivers is normally the result of industrial effluents, mine drainage and acid precipitation. Alkaline pollution is less common but may result from certain industrial effluents, and eutrophication (Dallas & Day, 1993).

The pH of natural waters plays an important role since it influences physical-chemical and biological processes in the aquatic environment. Relatively small changes in pH are not normally lethal, but although sub-lethal effects such as slow growth and reduced fecundity may occur due to increased physiological stress placed on the organism by increased energy requirements (Dallas & Day, 1993).

Changes in pH of recreational waters may trigger chemical transformations resulting in eye, skin, ear and mucous membrane irritation (South African Water Quality Guidelines (Volume 2&7), 1996). t) Total dissolved solids: One of the major descriptors of the quality of a water sample is the total amount of material dissolved in it. This property of water is commonly measured in one of three ways: as total dissolved solids, as conductivity, or as salinity, all of which correlate closely in most waters. Since the electrical conductivity of water is a function of the number of charged particles (ions) in solution, it is also a measure of the total quantity of salts, and therefore of total dissolved solids, in a sample of water. Conductivity does not measure any un-ionized solutes. Thus in waters very rich in dissolved organic compounds (non-ionic), for instance, this relationship does not hold particularly well. The constituent inorganic salts govern the effects of the total dissolved solids. The proportional concentrations of the major ions effect the buffering capacity of the water hence the metabolism of organisms. Secondary effects include those on water chemistry, which in turn effect the fate and impact on the aquatic environment on other chemical constituents

23 or contaminants. Natural waters contain varying quantities of total dissolved solids as a consequence of the dissolution of mineral in rocks, soils and decomposing plant material. Total dissolved solid concentrations also depend on physical processes such as evaporation and rainfall (Dallas & Day, 1993; Hellawell, 1986; South African Water Quality Guidelines (Volume 2 &7), 1996).

2. Chemical constituents

2.1 Dissolved oxygen: Gaseous oxygen (02) in atmosphere dissolves in water and is also generated during photosynthesis by aquatic plants and phytoplankton. The maintenance of adequate dissolved oxygen concentrations is critical for the survival and functioning of aquatic biota because it is required for the respiration of all aerobic organisms. Table 7 shows factors modifying the concentration of dissolved oxygen in water.

Table 7. Factors modifying the concentration of dissolved oxygen in water (Dallas & Day, 1993). INCREASE DECREASE Reaeration from the atmosphere (dependent on Respiration of aquatic organisms (plants and turbulence and oxygen deficit). animals) As atmospheric pressure increases, more As salinity increases, less oxygen dissolves in oxygen dissolves in the water. water. Photosynthesis of aquatic plants. Aerobic decomposition of organic material by micro-organisms. Low temperatures increase oxygen solubility High temperatures decrease oxygen solubility. Chemical breakdown of pollutants.

Dissolved oxygen concentration provides a useful measure of the health of an aquatic ecosystem. It is important to distinguish between dissolved oxygen concentration, measured for instance as mg/1, and percentage saturation. Percentage saturation is the proportion of oxygen that actually dissolved in water relative to the theoretical maximum calculated from tables, taking into account salinity and pressure. Percentage saturation gives a useful estimate of biological activity. Concentration is also an important measurement because it is the absolute amount of oxygen that organisms require, rather than the percentage saturation.

24 Measurement of the biological oxygen demand (BOD) or the chemical oxygen demand (COD) are inappropriate for aquatic systems, but are useful for determining water quality requirements of effluents discharged into the systems, in order to limit their impact. The breakdown of certain chemicals results in the lowering of dissolved oxygen concentrations. The chemical oxygen demand is a measure of the oxidation of reduced chemical species in water, i.e. the reducing capacity of an effluent (Dallas & Day, 1993; South African Water Quality Guidelines (Volume 2 &7), 1996).

2.2 Macro-elements: Alkalinity: Alkalinity is largely determined by the concentration of hydroxyl ions, (OH); bicarbonate ions (HCO3); and carbonate ions (C03 2)). Briefly, carbon dioxide dissolves in water to form carbonic acid (H2CO3) which, depending on pH, dissociates to form carbonate, bicarbonate and hydrogen ions (South African Water Quality Guidelines (Volume 2 &7), 1996): CO2 + H2O H H2CO3 +-+ HCO3 - + H+ H C032- + 2H+ (At pH values of 6.4-8.6 they are in the form HCO3 -) These ions are formed as a result of the interaction of carbon dioxides in the water with basic material such as the calcium carbonate or chalk or limestone in soils and rocks (Ellis, 1989): CO2 + CaCO3 +H20 Ca(HCO3)2 Alkalinity is primarily controlled by carbonate species and is therefore usually expressed in terms of equivalence to calcium carbonate (CaCO3). Water alkalinity is defined as the ability of solutes in water to neutralize added strong acids. Highly alkaline water often has a high pH value and contains elevated levels of dissolved salts. Alkalinity serves as a pH buffer and reservoir for inorganic carbon, thus helping to determine the ability of water to support algae growth and other aquatic life (Manahan, 1993).

Calcium: Of the cation found in most freshwater systems, calcium generally has the highest concentration and often has the most influence on the aquatic chemistry and water uses and treatment. Calcium is a key element in many geochemical processes, and minerals

25 constitute the primary sources of calcium ion in waters. Among the primary contributing minerals are gypsum, anhydrite, dolomite, and calcite and aragonite (Manahan, 1993). Calcium is present in water as a consequence of equilibria between calcium and magnesium carbonate minerals and carbon dioxide dissolved in water, which it enters from the atmosphere and from decay of organic matter in sediments. These relationships are depicted in figure 10.

CO2

CaCO3 + CO2+ H2O *--> Ca2++ 2 HCO3"

CaCO3

Sediment

Figure 10. Carbon dioxide-calcium carbonate equilibria (Manahan, 1993).

Calcium ion, along with magnesium and sometimes iron(II) ion, accounts for water hardness. The most common manifestation of water hardness is the crudy precipitate formed by the reaction of soap (Manahan, 1993). c) Ammonia: Un-ionized ammonia (NH3) is a colourless, acid smelling gas at ambient temperature and pressure. It is produced naturally by the biological degradation of nitrogenous matter and provides an essential link in the nitrogen cycle. Ammonia (NH3) may be present in the free unionized form or in the ionized from as the ammonium (NH4 +). The toxicity of ammonia is directly related to the concentration of the un-ionized form (NH3), the ammonium ion (NH4+) having little or no toxicity to the aquatic biota. The ammonium ion (NH4+) does, however contribute to eutrophication. Water temperature and pH are the

most significant factors that affect the proportion and toxicity of un-ionized ammonia. An increase in either results in an increase in toxicity. Un-ionized ammonia affects the respiratory systems of many animals, either by inhibiting cellular metabolism or by decreasing the oxygen permeability of the cell membrane (Dallas & Day, 1993; Ellis, 1989; Hellawell, 1986; South African Water Quality Guidelines (Volume 2 &7), 1996) d) Nitrate: Nitrates are the end products of the aerobic stabilization of organic nitrogen (figure 8) and may enter the water via fertilizers, agricultural runoff etc. In spite of their many sources, nitrates are seldom abundant in natural waters (normally<0.1mg/1 N), because photosynthetic action is constantly converting them to organic nitrogen in plant cells. They do however contribute in the end to contribute to eutophication (Dallas & Day, 1993; Ellis, 1989; Hellawell, 1986; South African Water Quality Guidelines, 1996) N2 Nitrogen Fixation Algal N

NH3 NH3 4 NO3_ 4 No3_ ORG-N ORG-N INPUT OUTPUT

NH3 -÷ NO2

Ai Bacteria 11r,

ORG-N f NO3

Denitrification Sediments N2

Figure 11: Schematic representation of the nitrogen cycle (Golterman, 1975 in Dallas & Day, 1993)

27 e) Nitrite: Nitrite is a naturally occurring anion in fresh and saline waters. Human activities that increase nitrite concentration in aquatic environments include industrial production of metals, dyes and celluloids, sewage effluents and certain types of agriculture. It is the intermediate in the conversion of ammonia to nitrate (figure 11) and is toxic at certain concentrations. Toxic effects of nitrite are modified by water chemistry, particularly by chloride concentration (nitrite toxicity increases as chloride concentrations decrease). Nitrite cause anoxia in fish (Dallas &Day, 1993). f)Chloride: Chloride is the major anion in sea water and in many inland waters, particularly in South Africa. Chloride ions are essential components of living systems, being involved in the ionic, osmotic and water balance of body fluids. Except where they have an effect by increasing the total dissolved solids, they exhibit no toxic effects on living systems (Dallas & Day, 1993). g) Phosphorus: Phosphorus can occur in numerous organic and inorganic forms, and may be present in waters as dissolved and particulate species. Elemental phosphorus does not occur in the natural environment. Orthophosphates, polyphosphates, metaphosphates, pyrophosphates and organically bound phosphates are found in natural waters. Of these, orthophosphate species H2PO4and HPO4-2 are the only forms of soluble inorganic phosphorus directly utilized by aquatic biota. Phosphorus has a major role in the structure of nucleic acids and in molecules involved in the storage and use of energy cells of aquatic biota. The most significant effect of elevated phosphorus concentrations is its stimulation of the growth of aquatic plants. Both phosphorus and nitrogen limit plant growth, and of these, phosphorus is likely to be more limiting in fresh water. Inorganic phosphorus concentrations of less than 0.005mg P/1 are considered to be sufficiently low to reduce the likelihood of algal and other plant growth. Point-source discharges of inorganic phosphor include domestic and industrial effluents, and discharges from diffused sources (non-point sources) is generated by surface and sub-surface drainage. Other diffused

28 sources include: atmospheric precipitation, urban run-off and drainage from agricultural land, in particular from land on which fertilizers have been applied (South African Water Quality Guidelines (Volume 2 &7), 1996) (Dallas & Day, 1993; Ellis, 1989; Hellawell, 1986; South African Water Quality Guidelines (Volume 2 &7), 1996).

Sodium: Sodium is ubiquitous in natural waters and is the major cation in sea water and in many South African inland waters. It is the major cation involved in ionic, osmotic and water balance in all organisms and is also involved in the transmission of nervous impulses and in muscle contration. Sodium is probably the least toxic metal cation (Hellawell, 1986) and its effects on aquatic systems are almost entirely as a major contributor to total dissolved solids (Dallas &Day,1993).

Suphates: Sulphur in water occurs largely as the sulphate (S04 2") ion. In living systems, sulphur is an essential component of proteins and is thus an essential element. In most natural waters, sulphate ions tend to occur in lower concentrations than bicarbonate or chloride ions. Sulphates themselves are not toxic. In excess, however, they form sulphuric acid, which is a strong acid that reduces pH and can have devastating effects on aquatic ecosystems. This is particularly problematic in water seeping from mines, where sulphate levels can be extremely high. In anaerobic conditions, sulphate ions are reduced to hydrogen sulpide, which has a strong tendency to become oxidized and is thus an oxygen "scavenger". Hydrogen sulphide, or "bad egg gas", is therefore an indicator of reducing conditions (Dallas&Day, 1993). It is also toxic, inhibiting a number of enzymes (Hellawell, 1986).

2.3 Trace metals:

The word metal is defined as an element which is a good conductor of electricity and whose electrical resistance is directly proportional to the absolute temperature. Trace metals are defined, in geological terms, as those occurring at 1000ppm or less in the earth's crust. Trace metals can be divided into two groups: those which occur naturally in

29 trace amounts in most waters, most of which are plant nutrients [cobalt, copper, manganese, molybdenum & zinc]; and those which usually do not occur in measurable amounts in natural waters, are potentially toxic in low concentrations, and have been widely distributed as a result of human activities [cadmium, lead, & mercury]. The term "heavy metals" refers to those metals with an atomic mass greater than that of calcium (40.078) and excludes sodium, potassium, manganese, lithium, aluminum, and beryllium. Table 8 differentiates the metals into three basic categories according to their toxicity and availability in natural aquatic systems: non-critical; toxic but insoluble or very rare; and very toxic and relatively accessible (Forsterner & Wittman, 1981). The abundant and heavy metals are indicated.

The main sources of trace metals in water bodies are geological weathering, atmospheric sources, industrial effluents (smelting & refining industries, coal-burning industries, iron & steal producing industries), agricultural run-off and acid mine drainage (from both direct discharge and leaching from the spoils of operation and abandoned mines)(Dallas & Day, 1993; Forsterner & Wittman, 1981).

Table 8. Classification of metals according to toxicity and availability (modified from Dallas &Day, 1993; Forsterner & Wittman, 1981). NON-CRITICAL :.TOXIC BUT INSOLUBLE VERY TOXIC AND OR VERY RARE RELATIVELY ACCESSIBLE Na*, K*, Mg*, Al*, Li, Ca*, Ti*, Hf, Zr, W, Nb, Ta, Re, Be, Co, Ni, Cu, Zn, Sn, As, Se, Fe*, Rb, Sr. Ga, La, Os, Rh, Ir, Ba. Te, Pd, Ag, Cd, Pt, Au, Hg, Tl, Pb, Sb, Bi Italics: Atomic mass < 40.078 (i.e. not a heavy metal) *: Abundant in the earth's crust (i.e. not defined as trace metals)

a) Aluminum: Aluminum is one of the more toxic of the trace metals and is probably not an essential nutrient in any organism. It is one of the elements whose solubility is strongly pH- dependant, and whose toxicity depends on the chemical species involved. At alkaline pH- values, aluminum is present as a soluble but biologically unavailable hydroxide complex. At intermediate pH-values, it is sparingly soluble and probably occurs as hydroxo- and

30 polyhydroxo-complexes. Under acid conditions, it occurs as solluble, available and toxic hexahydrate (aquo) species. The mechanism of toxicity at biochemical level is poorly understood. Aluminum is found in soluble form mainly in acid mine drainage and is becoming a variable of concern in natural waters affected by acid rain (Dallas & Day, 1993). b)Cadmium: Cadmium (Cd) is one of the trace metals classified as a hazardous candidate. It is easily absorbed by mammals, in which it is concentrated by binding with protein called metallothionein. Cadmium accumulates thus in tissues. It is known to inhibit bone repair mechanisms, and to replace zinc in zinc-containing metalloenzymes, and to be teratogenic, mutagenic and carcinogenic (Dallas & Day, 1993; Heath, 1993; Hellawell, 1986; Prosi, 1979; Patrick, 1994; Wilhm & Dorris, 1968). c)Cobalt: Although cobalt is an essential micronutrient, being an instant component of cobalamin (vitamin B), It is also toxic in fairly small quantities. The insoluble inorganic cobalt compounds e.g. hydroxides, carbonates and oxides; are carcinogenic when injected into mamals, while soluble ones e.g. chlorides, nitrates and sulphates; are toxic, inhibiting some enzymes and stimulating others. Its toxicity and availability in the environment are low and so cobalt is not generally considered to be a particularly ecotoxic trace metal (Dallas &Day, 1993). d)Copper: Copper is a micronutrient, forming an essential part of cytochrome oxidase and various other enzymes involved in redox reactions in the cell. Nonetheless it is a toxic heavy metal at low doses and is known to cause brain damage in mammals. In water copper is mobile and soluble at low pH; it precipitates in alkaline conditions and is thus then non- toxic. Copper readily form complexes with a wide range of other substances commonly found in clean and polluted waters and is also readily absorbed onto suspended solids. It is thought that these properties, together with the attendant difficulties in separating the chemical species of copper, may account for the variability that may appear in some

31 results. The effect of elevated copper concentrations on aquatic organisms is also related to factors such as the duration of exposure and life stage of the organism. Studies have shown that species richness and species composition of invertebrate communities changed as copper concentrations increased (Dallas & Day, 1993; Heath, 1993; Hellawell, 1986; Prosi, 1979; Patrick, 1994; Wilhm & Dorris, 1968). e)Chromium: Chromium is one of the least toxic of the trace metals at low concentrations and is in fact essential for fat and carbohydrate metabolism in mammals. Chromium is a relatively scare metal, and the occurrence and the amounts thereof in aquatic ecosystems are usually very low. Most elevated levels of chromium in aquatic systems are a consequence of industrial activity. Hexavalent chromium salts are used: in metal pickling and plating in the leather industry as tanning agents, and in the manufacture of paints, dyes, explosives, ceramic and paper. Trivalent chromium salts are used much less frequently, but are important as: fixatives in textile dye manufacture, in the ceramic and glass industry, and in photography (Dallas & Day, 1993; Ellis, 1989; Hellawell, 1986; South African Water Quality Guidelines (Volume 2 &7), 1996). f)Iron: Iron is the fourth most abundant element in the earth's crust and may be present in natural waters in varying quantities depending on the geology of the area and the chemical properties of the water body. Iron is naturally released into the environment from weathering of sulphide ores (pyrite, FeS2) and igneous, sedimentary and metamorphic rocks. Leaching from sandstone releases iron oxides and iron hydroxides to the environment. Iron is also released into the environment by human activities, mainly from the burning of coke and coal, acid mine drainage, mineral processing, sewage, landfill leachates and the corrosion of iron and steel. Most iron in oxygenated waters occurs as ferric hydroxide in particulate and colloidal form and as complexes with organic,

32 especially humic, compounds. Iron compounds are easily oxidized and therefore high concentrations of reduced forms can result in oxygen depletion in the environment. Iron is an essential macronutrient in all organisms, forming an essential part of haeme- containing respiratory pigments, catalases, cytochromes and peroxidases. Although it has toxic properties at high concentrations, inhibiting various enzymes, it is not easily absorbed through the gastro-intestinal tract of vertebrates (Dallas & Day, 1993; Ellis, 1989; Hellawell, 1986; South African Water Quality Guidelines (Volume 2 &7), 1996).

Manganese: Manganese is an essential micronutrient. A deficiency in manganese in vertebrates leads to skeletal deformaties but high concentrations are toxic, leading to disturbances in various metabolic pathways (Dallas &Day, 1993).

Nickel: Nickel is certainly toxic, even in fairly small quantities, inhibiting cytochrome oxidase and various enzymes in the citric acid cycle. It also becomes bound in various proteins. At pH values less than 6.5 nickel tends to be soluble. About half the nickel present in fresh waters is in the ionic from and the other half in stable organic, often humic, complexes (Dallas & Day, 1993).

Lead: Lead is defined by the USEPA (United States Environmental Protection Agency) as potentially hazardous to most forms of life, and is considered toxic and relatively accessible to aquatic organisms (South African Water Quality Guidelines (Volume 7), 1996). It tends to accumulate in living tissues, and in invertebrates, to become immobilized in bone, where it does not exhibit toxic effects. When bone becomes remobilized, as in fever, or as a result of cortisone therapy, or during old age, however, the lead may be released and then exerts it toxic effects. A major effect of lead is the result of its interference with the synthesis of haeme, an essential portion of the haemoglobin molecule. It also effects membrane permeability, displacing calcium at functional sites and inhibiting the opening of the "calcium pump" in membranes, as well

33 as inhibiting some enzyme involved with energy metabolism. It has also been implicated in reduced immune response in mammals (Dallas & Day, 1993). j) Zinc: Zinc is an essential macronutrient, forming the active site of various metalloenzymes; including DNA and RNA polymerases. It is known to bind to mellothionien in mammals. There are few reported cases of zinc poisoning, even in mammals (Dallas & Day). Zinc occurs in rocks and ores and readily refined into a pure stable metal (Dallas & Day, 1993; Ellis, 1989; Hellawell, 1986; South African Water Quality Guidelines (Volume 2 &7), 1996).

3. Microbiological constituents:

Fresh water recreation in water bodies not receiving continuous maintenance provides an important route of exposure to water-associated pathogens. A wide range of infectious diseases can be transmitted. Infection may occur by ingestion, inhalation or surface contact (South African Water Quality Guidelines (Volume 7), 1996). Control of the quality of our inland lakes and dams greatly depends on the quality and quantity of discharges entering the water, such as treated wastewater effluent and run-off discharges. Other pollutants may be natural inhabitants of fresh water which may cause human diseases, or the bathers themselves may be the source of pollution (Kfir, 1992). a) Coliforms and E. coli: Total coliform bacteria are frequently used to assess, the general hygienic quality of water, while faecal coliforms are widely used as indicators of faecal pollution. The presence of Escherichia coli is used to confirm the presence of faecal pollution by warm- blooded animals. It is used to evaluate the possible faecal origin of total and faecal coliforms. E. coli usually comprises approximately 97% of coliform bacteria in human faeses. Faecal coliforms and E. coli are rarely found in soil or water, which has not been subjected to faecal pollution (South African Water Quality Guidelines (Volume 2), 1996). 34 4.2.2 Water quality guidelines.

Water quality guidelines are a set of information for a specific water quality constituent. It consists of the target water range (TWQR), and the water quality criteria, chronic effect value (CEV) and acute effect value (AEV). Included with this information the water quality guidelines also provides the occurrence of the constituent in an aquatic environment, the norms used to assess its effects on water uses, and the conditions for case-, site-, and region specifications (South African Water Quality Guidelines (Volume 2&7), 1996).

The water quality requirements of the different user groups are not necessarily the same. These differences imply that water, which would ideally be fit for use for one specific user group, may not be fit for another. In South Africa Five main water users for inland surface water are commonly recognized: domestic recreational industrial agricultural natural environment This study will refer to the following two types of water quality guidelines: South African Water Quality Guidelines (Volume 2), Recreational Use and South African Water Quality Guidelines (Volume 7), Aquatic Environment. The water quality criteria provided by South African Water Quality Guidelines (Volume 2), Recreational Use and South African Water Quality Guidelines (Volume 7), Aquatic Environment are shown in table 9-11.

4.2.3 Water quality criteria.

The acceptability of levels or concentrations of specific water quality constituents, and the protection afforded to aquatic systems, can be assessed against the water quality

35 criteria given in the water quality guidelines. In the constituent-specific criteria, a numerical value or range for each constituent of concern represents a level of ecological risk associated with the presence of that constituent in the water (Dallas & Day, 1993; South African Water Quality Guidelines (Volume 2&7), 1996).

The target water quality range (TWQR) is a management objective and refers to the range of concentrations or levels in which no measurable adverse effects are expected on the health of aquatic systems, and therefore ensure their protection. The chronic effect value (CEV) is defined as that concentration or level of a constituent at which there is expected to be a significant probability of measurable chronic effects up to 5% of the species in the aquatic community. If such chronic effects persist for some time and/or occur frequently, they can lead to eventual death of individuals and disappearance of certain species from aquatic ecosystems. The acute effect value (AEV) is defined as that level of a constituent above which there is expected to be a significant probability of acute toxic effects up to 5% of the species in the aquatic community. If such acute effects persist for even a short while, or occur at too high frequency, they can quickly cause death and disappearance of sensitive species or communities from an aquatic ecosystem (South African Water Quality Guidelines (Volume 2&7), 1996).

Table 9. Water quality criteria for microbiological factors of water taken from South African Water Quality Guidelines, Volume 2, 1996. I -Microbiclogicalfactors . Constituent SOUth-AfricanNatdr:Quality Guidelines olurne 2), Recreational Use 1996. Target 'water.: Chronic water- Acute water .quality effect quality effect quality - effect value , value, valUe E. Coli 0-126 126-400 >400 (counts/100m1)

Col iforms 0 - 1000 1000-4000 >4000 (counts/100m1)

36 Table 1 0. Wa ter quality criteria for physical factors of water taken from South African Water Quality Gu idelines, Volume 2& 7, 1 996. 1. PhysicalFac tors Constituent South African Water Quality Guidelines (Volume 7), South African Water Quality Guidelines (Volume 2), Aquatic Environment, 1 996. RecreationalUs e, 1 996. Target water Chronic water Acute water qual ity effect value it quality effect value quality effect value Temperature Water temperature should not be allowed to vary from the background average daily water temperature cons idered to be normalfor that spec i fic site and time of day, by >2°C, or by 1 0%, whichever estimate is more conservative. Floating Water should be free of floating or submerged debris, which may matter/re fuse injure, tangles or obstructs water users. Shorelines should be free of litter. Recreational water should also be free of wastewater or other discharges, and substances in amounts that would cause an adverse visual impact or affect aquatic life forms. This includes oil, scum, foam, and substances, which from a visible fi lm on, or discoulor noticeable deposits on bottoms and shore lines. Odour Recreational water should be free of any substances, which cause noticeably unpleasant or objectionable odours. Odours detract from aesthetic enjoyment of water and are considered by water users as indicative of water pollution. Clarity and co lour It is feasible to propose a numerical guideline for co lour due to the wide variation in background colour preference. However recreational water shou ldbe virtually free of substances introduced by the activities of man and which cause objectionable or abnormal colour. Non-natural colour such as dyes should not be present at concentrations perceptible to human eye. Such colour distracts from pleasure viewing water in its natural state. pH (alkal in ity & pH- values shou ld not be a l lowed to vary from the range of t he M in imal eye irritation occurs in the target gu idel ine range of 6. 5-8.5. ac idity) background pH-values for a spec i fic site and time of day, by> The pH of water is we ll within the buffering capac ity of the lachrymal 0.5 of a pH un it, or by > 5%, and should be assessed by which flu id of the human eye. est imate is more conservat ive. 37 Table 10. (Con tinue)

2. Chemical Factors Constituent South African Water Quality Guidelines (Volume 7), South African Water Quality Guidelines (Volume 2), Aquatic Environment, 1996. RecreationalUse, 1996. Target water Chronic water Acute water qual ity effect value quality effect value quality effect value 0 — tr, — v

Ammon ia (µg/1 NH3) C) CD — 0 Acid-soluble V Aluminum — kr1

ium(pg/I Ca) V 0.3 0 . Cadm 5E I Chloride (pg/I C I ) <0.2 CD C•1 , v rq V V :1 - Chrom ium (µg/1 Cr Ill) CD C3 — "7

Chrom ium (gg/I Cr VI) -- 1/4... ,, en C.) ..... V 4.). 0 a.) al 1:1 0. ,..1 =,. . , 10.53 v 0 0 — - Fluoride (µg/1 F) <750 ■ 2 540 _ 3S 2. Chemical factors (continue) Constituent South African Water Quality Gu idelines (Volume 7), South African Water Quality Guidelines (Volume 2), Aquatic Env ironment_ 1996. Recreational Use, 1 996. Target water Chronic water Acute water quality effect value quality effect value quality effect va lue u — ,—, 1... o C c.. ...

a.) GA The iron concentration shou ld not be al lowed to vary by more than 1 0% of the background d issolved iron concentration for a spec ific time. Dissolved Lead <0.2 (i.tg,/1 Pb) — rn rn r-- 0 0 Disso lved 0 Manganese (µ g/1 Mn) {6 co r — O c, -,:r V

Tota lMe rcury (µ g/1 1 1g) — ..., 2 on a.) c o E. c c U_ C — 1) • F inorgan ic nitrogen is obtained by adding

lual concentrations of ammon ia (NH3 , 403') and n itrite (NO2").Any assessmen t of could be coup led to inorganic phosphorous ystems typ ical ly have an N: P ratio greater pile most impacted (eutrophic and Is have an N: P ratio of less than 10: 1. At , nitrogen fixation is likely to occur, this

, nalin organ ic nitrogen to the system. In ygenated (d isso lved oxygen concen tration

► waters, most (>80%) of the inorganic present as n itrate; typica lly, ammon ia be below 0. 1mgN/1. Where e ffluent g high ammon ia or nitrate concentrations aerobic waters, background inorgan ic >ns rise. This wil l usually be accompan ied e d issolved oxygen concentrat ion and an COD, and pH. I 2. Chem ical Constituents (Continue) Constituents er Quality Guidelines (Volume 7), South African Water Quality Guidelines (Volume 2),

mt 1 996. T 1 nAc Target water Chronic water Acute water quality effect value quality effect value quality effect value s.0 . e o o 00 6 N CD ei. .1- s A A " ' I Z

I Dissolved Oxygen c 0 ...... to ,,, 0 = U

Inorganic phosphorus concentrations shou ld not be changed by ..a ..c a w a T.- = ui . more then 15% from that of the water body under local, unimpacted conditions at any time of year; and the trophic status of the water body shou ld not increase above its present level, though a decrease in the trophic leve lis perm iss ible; and the amplitude and the frequency of natural cycles in inorganic phosphorus concentrations shou ld not be changed. Victoria Lake is currently an eutrophic system and average summer inorgan ic phosphorus concentration shou ld range from 25-250 VD (---) vr) ( re; v Dissolved Zinc 1 Zn) 40 5.DATA COLLECTION AND ANALYSIS. Data and information was retrieved from different sources: a) Germiston Council: Germiston council monitors the major inlets to Victoria Lake on a regular basis. The results were forward to the researcher for the period, starting July 1997 to June 1998. The Germiston Council Monitored the following constituents for sites 1,3, 4&5 combined, and site 6 (see figure 3, photos 1„3,4&5,6): Chemical Constituents: > Macro-elements: Ammonia, Chemical Oxygen Demand, Orto-phosphates, Sodium. > Metals: Cadmium, Chromium, Copper, Iron, Nickel, Lead, Zinc. Micro-Biological Constituents: Coliforms, E. coli.

b) Data Collected on site: Added to these analyses, water was sampled by the researcher once a month from July 1997 to June 1998 at six sampling sites (see figure 3, photos 1-6) within the inlets around Victoria Lake. The following variables were determined on site at each locality (see Appendix 5): Physical Constituents: Clarity and colour of the water, Conductivity (Jenway, model, 4070), Floating matter/refuse, Odour, Water Temperature (WTW microprocessor, model OXT 96), pH (ORION, model SA250). Chemical Factors: Dissolved Oxygen and Percentage Saturation Oxygen (WTW microprocessor, model OXT 96)

41 Readings were taken between 10:00am and 15:00 p.m. All equipment used for the collection and processing of water was thoroughly cleaned and acid washed to remove all traces of metals according to procedures described by Giesy and Wiener (1977). c) The Department of Chemistry, RAU: Water was sampled and placed in cleaned and acid washed bottles by the researcher at the six sampling sites (see figure 3, photos 1-6) within the inlets around Victoria Lake. Two water sample bottles were sent to the Department of Chemistry, RAU, every month during the period of July 1997 to January1998. The water contained by one of the sample bottles was filtered while the other one remained unfiltered. The Department of Chemistry analyzed the water samples for the following constituents (see Appendix 3): a) Chemical Constituents: ➢ Macoro-elements: Calcium (Unfiltered) ➢ Metals: Aluminum (Filtered and Unfiltered), Copper (Filtered and Unfiltered), Cadmium (Filtered and Unfiltered), Cobalt (Filtered and Unfiltered), Chromium (Filtered and Unfiltered), Iron (Filtered and Unfiltered), Lead(Filtered and Unfiltered), Manganese (Filtered and Unfiltered), Nickel (Filtered and Unfiltered), Zinc (Filtered and Unfiltered). c) Rand Water: Rand Water Laboratories also took part in analyzing some of the water samples collected by the researcher. Water samples were collected and placed in cleaned acid washed bottles at the six sampling sites every month for the period of July1997 to June 1998. These water samples were not filtered. These samples were used to analyze macro-elements. A further two bottles were collected from February 1998 to June 1998.One of these samples were filtered the other one remained unfiltered. These samples were used for trace metal-analysis. Rand Water analyzed the following constituents (see Appendix 4): 42 Physical Constituents: Alkalinity(Unfiltered), Suspended Solids (Unfiltered). Chemical Constituents: > Macro-elements: Ammonia(Unfiltered), Calcium (Unfiltered), Orto-phosphates (Unfiltered), Nitrate (Unfiltered), Nitrite (Unfiltered), Sulphate (Unfiltered), Chloride (Unfiltered), Chemical Oxygen Demand (Unfiltered). > Metals: Aluminum(Filtered and Unfiltered), Cadmium (Filtered and Unfiltered),Chromium (Filtered and Unfiltered), Cobalt (Filtered and Unfiltered), Copper (Filtered and Unfiltered), Iron (Filtered and Unfiltered), Manganese (Filtered and Unfiltered), Lead (Filtered and Unfiltered), Nickel (Filtered and Unfiltered), Zinc (Filtered and Unfiltered)

The water quality criteria provided by South African Water Quality Guidelines (Volume 2), Recreational Use and South African Water Quality Guidelines (Volume 7), Aquatic Environment shown in table 9-11, will then be used to evaluate all the collected data. The data will also be compared where possible and discussed.

5.1 Shortcomings of the data.

Water analysis requires not only the subtle correlation of theory and experience of analytical principals but also a keen insight into the nature of interference and other problems associated with the methodology. Interference may be quite unique to a particular water system and in many ways yield inaccurate data and cause misleading conclusions (Mancy, 1971).

The following list gives some of the problems associated with the water analysis of this study: • A major problem in all the sampling exercises was that of obtaining a representative sample. In all natural waters, trace element concentrations varied with depth, salinity, and the proximity to discharge points (Batley, 1989).

43 The samples were collected at regular intervals, which leads to the possibility that the results will be influenced by cyclic fluctuations in metal concentrations which are in phase with the sampling program (Allen, 1971). Natural waters are mixtures containing biological and chemical species in dynamic equilibrium, which can be disturbed by the mere act of sampling. This could be brought about by the exposure to oxygen or to the container walls, or as a result of the changes in temperature or pressure (Batley, 1989). Errors that could possibly be introduced in sample collection, preparation, and storage during this project are contamination, and losses of chemical constituents (Batley, 1989). The chemical surveys of the water samples collected only indicated the water conditions at the time of sampling and did not easily detect short-term events, such as occasional spills of highly concentrated waste, which may be critical to the ecosystem health of Victoria Lake (Hellawell, 1986). Metals in the water were often present in concentrations that were below the detection limits with the available analytical method, but it can still be high enough to produce adverse effects on aquatic organisms of Victoria Lake (Heath, 1993; Prosi, 1979; Patrick, 1994; Wilhm & Dorris, 1968). The water analysis that has been done, does not indicate the effects of metals on the organisms inhabiting Victoria Lake. Slight increases in the metal concentrations in the water could lead to significant increases in metal content of the organisms inhabiting the water because the organisms may also accumulate additional metals via the food chain. Organisms may also be exposed to various concentrations of metal levels since they move in and out of contaminated areas (where inlets enter Lake). The chemical analysis also fails to account for the rates of transformation of a chemical by biological organisms and the possible relocation of a chemical within the aquatic ecosystem due to abiotic adsorption and sedimentation. A further limitation of chemical monitoring is that it does not account for the many man-induced perturbations, such as flow alterations and habitat degradation, which impair biological health. Chemical attributes used in this study thus lack the responsiveness

44 necessary to evaluate the health of the aquatic ecosystem of Victoria Lake (Dallas & Day, 1993; Loeb & Spacie, 1994; Mance, 1987; Roux, et al., 1993; Saunders, 1997). The water criteria used only consider single metals rather than the effect of a mixture of toxic compounds that are present in the water (Farag, et al., 1994). As the effluents that enter the inlets contain many different compounds, unknown toxins may be over looked (Koeman, et al., 1978). The environmental conditions under which analysis was carried out in the laboratory were quite different from those that existed at the sampling site (Mancy, 1971). This study also compares results of chemical analysis which were analyzed at different laboratories, namely Germiston Council; RAU, Department of Chemistry, and Rand Water. Results of certain chemical analyzes done by Rand Water, were not completed due to insufficient samples. The water containers used during sampling were thus too small and there was not enough water available to perform all the chemical analyzes. Rand Water moved to a new laboratory and some of the samples were lost (all samples taken during February 1998). Chemical and physical water quality data collection done by Germiston Council were at irregular intervals. The South African Water Quality Guidelines that were used for this study had such low critical values(target water quality effect value, chronic water quality effect value and acute water quality effect value), that they were often out of range when graphs were drawn to show results. This resulted in the absence of these values on some graphs. The South African Water Quality Guidelines sets vague criteria for some constituents, for example: the constituents; total dissolved solids and iron. The Guidelines state that no deviation of more than 15% should be allowed for total dissolved solids from "the normal cycles of the water body under unimpacted conditions" and iron concentrations should not be allowed to vary by more than 10% of the "background dissolved iron concentration for a specific time". Since Victoria Lake used to be a mine dam it is difficult to determine the state of unimpacted conditions. 45 • For certain constituents measured (chemical oxygen demand), the South African Guidelines specified no criteria.

Water analysis requires the ability to properly interpret analytical results in correlation to the pertinent field observation and history of the water (Mancy, 1971). Analytical techniques that are employed in the monitoring of Victoria Lake should be sensitive, specific, accurate, easy and quick to carry out, cost effective and reliable (Mancy, 1971; Wittmann, 1979). The analytical chemist is expected to prescribe workable procedures and to optimize the techniques used in order to obtain the needed information. The needed information is determined by the objectives of the study (Mancy, 1971). It is therefore obvious that water quality analysis is often not perfect but that we should devise procedures that will best suite our study.

6. RESULTS AND DISCUSSION.

The chemical composition of inland water is determined by many factors, including soil and rock composition of the catchment area, climatic conditions, amount and chemical composition of rainwater, fauna and flora, and anthropogenic (human) influences (Forstner, 1979). The chemical composition can therefore vary both spatially, and temporally over relatively short periods of time. Results obtained from water analysis should thus always be interpreted with care.

To determine the water quality of the major inlets to Victoria Lake, certain constituents were examined and judged according to the South African Guidelines for an healthy aquatic environment and recreational use. These constituents can be divided under three major heading: physical constituents, chemical constituents and micro-biological constituents.

46 1. Physical constituents. a) Temperature: Temperatures recorded at all the major inlets were higher in the summer (November to April) than those recorded in the winter months (May to October) (see fig. 12 & table 5, Appendix 5). The month of September had higher water temperatures due to fairly high day temperatures. The changes in the water temperature measured within the inlets of Victoria Lake are generally related to natural variation (i.e. natural seasonal patterns and temporal variability) (Dallas & Day, 1993; Ellis, 1989; Hellawell, 1986; South African Water Quality Guidelines (Volume 2 &7), 1996). The inflows to Victoria Lake are generally swallow which may contribute to warmer water, although there is some variance in dept. Spatial variance in temperature could thus be expected. A study done on the water temperatures of Victoria Lake showed a variance in water temperature of 9- 24°C (Saunders, 1997).The temperatures from the inflow waters will therefore not have such a great effect since the variance of the inflow water is from 5 to 26°C.

30—

25— °C

20— -6"-- Site 1

ture —s-- Site 2 ra 15— • Site 3 Site 4

Tempe 10— Site 5 Site 6 5—

0—

07/97 08/97 09/97 10/97 11/97 12/97 01/98 02/98 03/98 04/98 05/98 06/98 Time

Figure 12. Temperature measured within the major inlets around Victoria Lake.

47 Floating matter/refuse: Floating matter and refuse were mostly present at sites 3, 4 & 5. Waste oil (especially at site 5), grease, plastic containers, bags, bottles and cans were often detected. Silt and litter traps to filter storm-water pollution, in combination with existing natural reed belts acts as a filtration device to minimize floating matter and refuse reaching Victoria Lake to some extent. These silt and litter traps, and reed belts are present at sites 3, 4 & 5. Floating matter and refuse can however still reach Victoria Lake and lead to aesthetically unattractive recreational waters.

Odour: Odour can indicate varied instances of pollution or an imbalance of a natural ecosystem (Dallas & Day, 1993; South African Water Quality Guidelines (Volume 2),1996). At sites 4 & 5 a noticeably unpleasant odour were frequently detected. This may be an indication of some sewage discharge. This can lead to Lake Victoria receiving water that is highly infected with water-associated pathogens. A wide range of infectious diseases can be transmitted this way and cause the waters of Victoria Lake to be declared as unfit for recreational use.

Clarity and colour: Due to organic activity and numerous amounts of suspended matter, site 1 had very low clarity. Water became highly laden with suspended material in the rainy season (Dallas &Day, 1993), and this might have contributed to the lack of clarity at site 1, although there was no improvement in the clarity of the water at this site when the rainy season stopped. This suspended material eventually becomes trapped in Victoria Lake, which result in great economic cost.

All of the inflow water at the sites investigated had an acceptable "natural" colour.

pH: The pH-values measured within the inlets around Victoria Lake from July '97 - June '98 (figure 13 & table 4, Appendix 5), showed that most of the values were within the target

48- water quality range set up by the South African Water Quality Guidelines (Volume 2). The highest pH value of 8.9 was measured at site 1. Sites 4 and 6 also had high values of 8.6 and 8.7 respectively. The lowest pH value of 5.6 was measured at site 4. The pH values of 5.7 and 6.3 were measured at site 4 and 3. The variation in the pH range may be effected by: The geology and geochemistry of rocks and soils gasses. Sandstone has virtually no buffering capacity because of the low mineral content. Victoria Lake is situated within a sandstone region (see section 3.3.1) (Dallas & Day, 1993; Ellis, 1989; Hellawell, 1986; South African Water Quality Guidelines (Volume 2 &7), 1996). Biological activity in natural systems. The intense photosynthetic activity of algae and higher plants may increase pH values above 8 up to 10 (Hellawell, 1986; South African Water Quality Guidelines (Volume 2 &7), 1996). This might be true for sites 1&2, since great numbers of algae were present within the inflow water.

Target water quality range

Site 1 --0— Site 2 —0— Site 3 Site 4 -o— Site 5 —0— Site 6

I I I I I i 1 1 1 1 I 7/97 8/97 9/97 10/97 11/97 12/97 1/98 2/98 3/98 4/98 5/98 6/98 Time

Figure 13. pH -values measured within the major inlets around Victoria Lake.

Nutrient cycling. Plant nutrients are any elements required for normal plant growth and reproduction. Nutrient enrichment termed eutrophication, can lead to an imbalance in biological communities, particular to the increase in plant and algae

49 growth. This might cause an increase in pH. Sources of nutrients may be fertilizers within surface run off water (Dallas & Day, 1993; Ellis, 1989; Hellawell, 1986; South African Water Quality Guidelines (Volume 2 &7), 1996). Site 1 is located at a golf course and is therefore exposed to surface runoff water polluted with fertilizers. Discharge of industrial effluents, acid mine drainage, run-off and decay processes. Low pH-values may result from one of the following three reasons: Point-source effluent produced by paper, leather/pulp industries, or acid mine drainage, deposition or precipitation of acid-forming substances into the aquatic environment. Victoria Lake is surrounded by an industrial area which may be responsible for acidification of the inflow water through acid rain or acid precipitation (Hellawell, 1986; South African Water Quality Guidelines (Volume 2 &7), 1996). The pH-values of the surface water from Victoria Lake ranged from 7.2 to 8.2 as shown in a study previously done by Saunders, 1997. The variance of the pH-values detected within the inlets (5.6-8.9), are much higher than that of the Lake and may eventually influence the pH-range of Victoria Lake. f)Total dissolved solids: This property of water is commonly measured in one of three ways: as total dissolved solids, as conductivity or as salinity (see section 4.2.1). This study measured total dissolved solids as conductivity. Electrical conductivity of water is the function of the number of charged particles (ions) in solutions, it is therefore also a measure of the total dissolved solids in a sample of water (South African Water Quality Guidelines (Volume 2 &7), 1996). In general the electrical conductivity measured at site 1, were much higher in comparison with the other sites (see figure 14 & table 1, Appendix 5). The highest value measured for electrical conductivity was at site 1 and was approximately 190011S/cm. Data gathered by Germiston Council revealed the variance of electric conductivity of the surface water of Victoria Lake to be between 200 and 2460µS/cm. The electrical conductivity measured at site 1 is thus still below the conductivity maximum (2460µS/cm) measured for Victoria Lake as shown in previous studies (Saunders, 1997).

50 •

2000 — 1900 — A 1800 — .... /\ \ 1700— .../ 1600— v ______.,, \ Vs A E 1500— ss \ "a3 1400 — \ / \ ' 1300—, Site 1 1200— \ / \ I. —0— Site 2 2.-2 1100— Ics, ,/N sass > 1000— -, ,,' / N„,, 7.11 900— - - Site 3 M 800— Site 4 V 700— C / 600— —0— site 5 • 0 500— 400— —0-- Site 6 300— 200— 100— 0—

7/97 8/97 9/97 10/97 11/97 12/97 1/98 2/98 3/98 4/98 5/98 6/98 Time

Figure 14. Electrical conductivity measured within the major inlets around Victoria Lake.

As mentioned before, site 1 is situated at a golf course and surface run-off waters may therefore contain numerous amounts of fertilizers which end up as salts in the inflow water. This may contribute to high amounts of total dissolved solids present in the inflow water at site 1.

2. Chemical Constituents.

2.1) Dissolved oxygen: The maintenance of adequate dissolved oxygen concentrations is critical for the survival and functioning of aquatic biota because it is required for the respiration of all aerobic organisms (Dallas & Day, 1995). An adequate supply of dissolved oxygen is essential for the maintenance of self purification processes in natural water systems (Canadian Water Quality Guidelines, 1992). It is important to distinguish between dissolved oxygen concentration, measured for instance as mg/1 (figure 15 A, see table2, Appendix 5), and

51 •

20 - 19 - 18 - Target water qualifY range 17 -

16 -. 15 - Site 1 to 14- Site 2 13 - 6, 12- Site 3 c 10 - Site 4 0) 9 - CD 8 Site 5 X 7 - 6 - Site 6 5 - Cronic effect value 4 3 2 1 0-

I 7/97 8/97 9/97 10/97 11/97 12/97 1/98 2/98 3/98 4/98 5/98 6/98 Time

Target water quality range 200 - 190- 180- Site 1 B) 170- --t--- Site 2 c 160 - 150 Site 3 co 140- 130- = Site 4 40-; 120- U) 110- Site 5 c 100- Site 6 0) 90 - 80 - X 70 60 - Chronic effect valu 50- 40- 30- 20- Acute effect value 10- 0-

I I .1 r 7/97 8/97 9/97 10/97 11/97 12/97 1/98 2/98 3/98 4/98 5/98 6/98 Time

Figure 15. Dissolved oxygen measured within the major inlets around Victoria Lake , A) Concentration dissolved oxygen, B) Percentage oxygen saturation. percentage saturation (figure 15B, see table3, Appendix 5). Percentage saturation is the proportion of oxygen that actually dissolved in water relative to the theoretical maximum calculated from tables, taking into account salinity and pressure. Percentage saturation

52 , gives a useful estimate of biological activity. Concentration is also an important measurement because it is the absolute amount of oxygen that organisms require, rather than the percentage saturation. Concentration dissolved oxygen (see figure 15A, table 2, Appendix 5) was generally within the target water quality range (>5.5 mg/1) as determined by the South African Water Quality Guidelines, 1996. The lowest values were measured at site 1 (1.15 mg/1, 1.75 mg/1, 0.49 mg/1, 0.5 mg/1, 1.01 mg/1), site 2 (1.96 mg/1, 0.07 mg/I, 1.91 mg/I, 2.46 mg/1) and site 5 (1.61 mg/1, 1.70 mg/1) during the summer months (September-February). Low values were also measured during early autumn (March & April). These values fell within the acute effect value as determined by the South African Water Quality Guidelines, 1996. These low levels may be related to the heavy rains that fell in the area prior to sampling. Site 1 and 2 are situated at a golf course. During the rainy season the amount of suspended silt and salts increased vastly. This cause drastic reductions in the concentration dissolved oxygen in the water (Buermann et. cd.,1995,1997). Oxygen depletion is also often caused by bacterial respiration during the decomposition of sedimenting organic matter (South African water quality guidelines,1996). At site 5 sewage was often noticed. The presence of oxidizable organic matter can also lead to the reduction in the concentration of dissolved oxygen (South African water quality guidelines,1996). The percentage oxygen saturation (figure 15B & table3, Appendix 5) compared to the concentration dissolved oxygen (figure 13A & table 2, Appendix 5) shows that these results are similar. The lowest values were again measured at sitel, site2 and site 5 during the same time period when low concentrations dissolved oxygen was measured. The reduction in oxygen levels is probably due to the heavy rains and the presence of oxidizable organic matter, either of natural origin or originating in waste discharges.

Previous studies of the dissolved oxygen levels of the surface waters of Victoria Lake show that the lowest value measured was 5.8 mg/1 and 78% (Saunders,1997). In comparison to these values the inlet values seem very low which might cause complications for Victoria Lake in the future. 53 • ▪

2.2) Chemical Oxygen Demand: The chemical oxygen demand (COD) is used as a routine measurement for effluents, and is a measure of the amount of oxygen likely to be used in the degradation of waste (South African water quality guidelines,1996).The chemical oxygen demand is a measure of the oxygen of reduced chemical species in the water, i.e. the "reducing capacity" of an effluent (Dallas & Day,1993). This study compares two sets of results: one set that has been collected by Germiston Council and a second set that has been collected by the researcher (see figurel6 A& B, Appendix 4, table 8). 'a 80- A) 0 v ---.,-- Site 1 70- A l I --o— Site 3 0E 60- / 1 / k st ''■ - -11- Site 4&5 d.- 50- /\ I I >, a) / \ / 1 —9— Site 6 x E 40- / 0 t ss.//\jk 1 k ii 30- \ ,.,P / I E 20- \ / A .---„.----61 o= 10- Time 7/97 8/97 9/97 10/9711/9712/97 1/98 2/98 3/98 4/98 5/98 6/98 70- R 65- Site 1 B) 60- 55- —0-- Site 2 0 50- c Site 3 CZ. 45- -6,3 40- Site 4 E 35- 30- O 0-- Site 5 25- a 20- a— Site 6 15- 10- C.) 5- 0 -

I I I I I I I I I I I I Time 7/97 8/97 9/97 10/9711/9712/97 1/98 2/98 3/98 4/98 5/98 6/98 Figure 16:Concentration Chemical oxygen demand measured within the inlets around Victoria Lake (water samples unfiltered) from June 97-July 98, A) Data received from Germiston Council; B) Data collected by the researcher and analyzed by Rand Water.

The South African water quality guidelines used in this study do not specify any target, chronic or acute effect values for chemical oxygen demand. However if the data is compared as seen in figure 16 A & B (see table 8, Appendix 4) it can be noticed that at sitel and at site 4 & 5 the oxygen demand is higher than 50 mg/l. This indicate that the water contain quite a high value of chemical species that can be reduced (Dallas &Day,

54 determination iftheyare present,aswillsaltofnaturalorganicacids such ashumicacid weak acidsalthoughonoccasionsitcouldbe due tothepresenceofweakbasesoreven strong bases.Borates, phosphates andsillicateswillalsobeincluded inthealkalinity of thewateratinletscanbeduetoelevated levelsofdissolvedsolids(Manahan, situated atESCOM(92-136CaCO3mg/1,see tablel,Appendix4).Thehighalkalinity of theinletsgenerallyhadahighalkalinity.The highestalkalinitywasmeasuredatsite3 chronic oracuteeffectvaluesforalkalinity.Figure17indicateshowever,thatthewater The SouthAfricanwaterqualityguidelinesusedinthisstudydonotspecifyanytarget, Figure 17.AlkalinityconcentrationmeasuredwithintheinletsaroundVictoriaLake(watersamples 2.3 Macro-elements: origin (detritus),ororiginatinginwastedischarges.Thisleadstoareductionthe H in waterrepresentsitsabilitytoneutralizestrongacids,i.e.thecapacityofaccept concentration ofdissolvedoxygenpresentinthewater(Dallas&Day,1993;Ellis,1989). unfiltered) fromJuly1997-June1998.DatacollectedbytheresearcherandanalyzedRandWater. in termsofequivalencetocalciumcarbonate(CaCO3)(refersection4.2.1).Alkalinity a) Alkalinity: 1993). HighpHvaluesarealsooftenassociated withhighalkalinewaters(Manahan, 1993). Ellis,1989statesthatalkalinityinsurface waterisprimarilyduetothepresenceof 1993). Thesechemicalspeciesincludeanyoxidizableorganicmatter,eitherfromnatural Alkalinity (Ca mg/I) Alkalinity isprimarilycontrolledbycarbonatespeciesandthereforeusuallyexpressed + 140 100- 120- ions(Manahan,1993). 80- 40- 60- 20- 7

7/97 11111111[ 8/97 9/97 10/9711/9712/97 Time 1/98 2/98 3/98 4/98 111 5/98 6/98

0 0-- Site5 — — Site6 Site1 Site 2 Site. 3 Site 4 55

(Ellis,1989). The low values measured at some sites may indicate poor buffering capacity on occasion (Dallas & Day, 1993). b) Calcium: Calcium is readily soluble in water, and it enters the aquasphere through the weathering of rocks, especially limestone, and from soil through seepage and runoff (Canadian water quality guidelines, 1992). 120-, Site 1

100- I) -dr-

/ Site .2 Site 3

mg 80-

Ca Site 4 ( 60- m 0-- Site 5 iu

lc 40- Site 6 Ca 20 o-

I I I I I I I I I I I I 7/97 8/97 9/97 10/9711/9712/97 1/98 2/98 3/98 4/98 5/98 6/98

Figure 18. Calcium concentration measured within the inlets around Victoria Lake (samples unfiltered) from July 1997-June 1998. Data collected by researcher and analyzed by RAU, Department of Chemistry (see Appendix 3, table2) and Rand Water (see Appendix 4 table 7) .

The South African water quality guidelines used in this study do not specify any target, chronic or acute effect values for calcium. High levels of dissolved calcium were present in all the inlets surrounding Victoria Lake (see figure 18, table 2, Appendix 3 & table 7, Appendix 4). Calcium ions are often the major cations in inland waters (Dallas&Day, 1993) and these high levels could be expected. The highest levels however, were measured at sitel (e.g.105.2 Ca mg/1). These higher levels of dissolved calcium at site 1 can be due to fertilizers containing lime used at the golf course and dissolving in run off waters during rainfall. High levels of dissolved calcium in the water are beneficial to organisms in metal contaminated environments since calcium can reduced metal toxicity by hinder the absorption of these metals by organisms (Kempster, et. a1.,1980). Previous studies did show an average calcium concentration range of (40 mg/I-70 mg/1) for the surface waters of Victoria Lake (Saunders, 1997), while the average calcium concentration of the inlet waters range from 25 mg/1-105.2 mg/l. Although we know

56 the targetwaterqualityeffectvalue(0.007mg/1), buttheyalsoexceededthechronic fluctuated greatlyandno apparenttrendscouldbeobservedintheconcentration ofthis effect value(0.015mg/1)asdetermined bytheSouthAfricanWaterQuality All thewatersamplestakenfrominflowsthat wereinvestigateddidnotonlyexceed Guidelines,1996 (see figure 19A&B,seetable4,Appendix4).Ammonium levels by researcherandanalyzedRandWater. unfiltered), fromJune1997-July1998,A)Datareceived fromGermistonCouncil;B)Datacollected Figure 19.Ammoniaconcentrationmeasuredwithin the inletsaroundVictoriaLake(Watersamples A) nitrification nitrite andthennitrate,withtheresultthatlevelsofthisionarerelativelylowif Ammonia isproducedduringthenaturaldegradationofnitrogenousorganicmaterialin concentration onaquaticbiotas(Dallas&Day,1993). calcium isavitalelement,verylittleknownaboutitsactualeffectsofchangesin surface waters(Ellis,1989).Underaerobicconditions,ammoniaisrapidlyconvertedto c) Ammonia:

Ammonia (mg/1) Amonia (NH3 mg/I) 4.5 4.0 5.0 2.5 3.0 3.5 2.0 0.0 0.5 1.0 1.5 4.00 3.75 2.00 2.25 2.50 2.75 3.00 3.25 3.50 0.00 0.25 0.50 0.75 1.50 1.75 1.00 1.25 processesareoperatingnormally(Dallas&Day,1993). , 7/97 8/979/9710/9711/9712/971/982/983/984/985/986/98 7/97 111111g 8/97 9/97 10/9711/9712/971/982/983/984/985/98 6/98 1 Time

Time -0- Site5 -a- ---D-- Site1 -9- --*- Site4&5 Acuteeffectvalue Site 1 Site 2 Site 4 Site 3 Site 6 Site6 Site 3 Acute effectvalue 57 ion. Sites 4 & 5 (Figure 19A) reached the highest value of 4 mg/l. Figure 19B, however shows that sites 1,4,5 and 6 all had high values varying from 1.8 mg/1- 5.1 mg/l.

Sources of ammonia include: Natural sources of ammonia include gas exchange with the atmosphere, excretion of organisms, nitrogen fixation, biochemical transformation of nitrogenous organic and inorganic matter (Dallas & Day, 1993; Ellis, 1989; Hellawell, 1986; South African Water Quality Guidelines (Volume 2 &7), 1996). Commercial fertilizers (Dallas & Day, 1993; South African Water Quality Guidelines (Volume 2 & 7), 1996). Site 1 might be effected by fertilizers since it is situated at a Golf Course. Sewage discharge (Dallas & Day, 1993; Hellawell, 1986; South African Water Quality Guidelines (Volume 2 &7), 1996). Sites 4 & 5 show the highest amount of ammonia measured. This may be due to sewage discharge since unpleasant odours were present. Discharge from industries that use ammonia or ammonium salts in their cleaning operations (South African Water Quality Guidelines (Volume 2 &7), 1996). Atmospheric deposition of ammonia from distillation and combustion of coal (Dallas & Day, 1993; South African Water Quality Guidelines (Volume 2 &7), 1996). Previous studies done show that the ammonia concentration of the surface waters of Victoria Lake varied from 0.01 mg/1 to 0.025 mg/1 (Saunders,1997). Results obtained from this study confirms that the inlet values are very high and will ultimately effect Victoria Lake. The most worrying factor is that site 6 is situated at the lake outlet. This might indicate that the lake might already have been effected. d) Nitrate: Nitrate (NO3") is the end product of the oxidation of organic nitrogen and ammonia (Dallas & Day, 1993). Nitrate is very stable and therefore will be more abundant in the aquatic environment. In view of the co-occurrence of nitrate and nitrite, they are usually measured and considered together, inter-linked with the occurrence of ammonia.

58 Because nitrite(NO2)isunstableinwaterand israpidlyoxidizedtonitratebybacterial (Kempster,et. action, thiscationis usuallyonlypresentinlowlevels surfacewaters e) Nitrite: inlets tothelakeincomparisonsurfacewaters ofthelakewerequitehigh. of thesurfacewatersVictoriaLaketorangebetween 1.1mg/1-3.5mg/l.Valuesofthe Previous studiesdonebySounders,1997,showed anaveragerangenitrateconcentration which maybethecauseoforganicwastesinwater. well industrialorganicwastes(SouthAfricanWaterQualityGuidelines,(Volume2&7) results fromdischargeofeffluentstreamscontaininghumanandanimalexcrementas 24 Appendix4).Majorsourcesofinorganicnitrogenwhichentersaquaticsystemsmay values ofnitrateweremeasuredatsites3,4&5(4mg/1-22mg/1)(seefigure20table however aconcernduetoitsstimulatoryeffectonaquaticplantgrowthandalgae.Thus excessive amountsofplantgrowthcanleadtothedevelopmenteutrophication.High chronic oracuteeffectvaluesfornitrate.Inorganicnitrogenintheformofnitrateis The SouthAfricanwaterqualityguidelinesusedinthisstudydonotspecifyanytarget, Water). Figure 20:NitrateconcentrationmeasuredwithintheinletsaroundVictoriaLake(watersamples unfiltered) fromJune1997-July1998(DatacollectedbytheresearcherandanalyzedRand 1996). Atsites4&5sewagewereoftennoticed,andsite3issituatedclosetoESCOM N itrate (mg/I) 20- 22- 18- 16- 14- 10 12 4- 6- 8- 2- 0- 7/97 8/979/9710/9711/9712/971/982/983/984/985/986/98 al., 1980). Time —v —0 —0 -0- 0— Site5 -- — -- Site1 Site2 Site4 Site6 Site 3 59 0.40- Site 1 .0.36- 0.32- Site 2 0.28- Site 3 C) 0.24- Site 4 0.20- Site 5 0.16- z 0.12- 0-- Site 6 0.08 0.04 0.00

111111111 111 7/97 8/97 9/97 10/9711/9712/97 1/98 2/98 3/98 4/98 5/98 6/98 Time

Figure 21: Nitrite concentration measured within the inlets around Victoria Lake (water samples unfiltered) from June 97-July 98 (Data collected by the researcher and analyzed by Rand Water).

The South African water quality guidelines used in this study do not specify any target, chronic or acute effect values for nitrite. The highest nitrite values were measured at site 1,3,4,5 and 6 (0.4 mg/1)(see figure 21 & table 25, Appendix 4). This may be explained by an increase of run off from the Golf Course due to rainfall (sitel, 2 & 6), discharge of effluent streams containing human and animal excrement (site 4 & 5) as well industrial organic wastes (site 3) (South African Water Quality Guidelines (Volume 2 &7), 1996). In previous studies done nitrite levels of the surface waters of Victoria Lake were below detection limits (<0.02 mg/1)(Saunders,1997).

0 Chloride: Chloride compounds are mobile and persistent complexing agents that may be of great significance in determining metal distribution in the environment (Hahne&Kroontje, 1973). The South African water quality guidelines used in this study do not specify any target, chronic or acute effect values for chloride. Chloride concentration measured within the inlets around Victoria Lake varied so much that no distinct pattern could be observed. High chloride values were measured at site 1 (160 mg/1), site 4 (156 mg/1) and site 6 (145 mg/1)(see figure 22, table 9, Appendix 4).Chloride is present in sewage effluents as NaC1 in urine (Klein, 1959). Sewage discharge might have taken place at site

60 4 since a bad odour was often noted at this site. High chloride values are also associated with brine discharges either from working geological deposits of rock-salt (halite) or from mining (Hellawell, 1986). Victoria Lake is situated in a mining area and this might be a reason for the high chloride values measured. Except where chloride have an effect by increasing the total dissolved solids, chloride exhibit no toxic effects on living systems (Dallas & Day, 1993). Chloride concentrations should however be monitored very closely in areas with a history of metal pollution (Bourg,1988) Studies done by Saunders, 1997, stated that the concentration chloride ions of the surface waters of the lake range from 20 mg/1-30 mg/l.

160- Site 140-

/ Site 2 120- Site 3 100- CI mg

( Site 4 80- ide

r --0— Site 5 60-

hlo —0-- Site 6

C 40-

20- o-

I I 1 I I 1 I I I 1 I 7/97 8/97 9/97 10/9711/9712/97 1/98 2/98 3/98 4/98 5/98 6/98 Time

Figure 22. Chloride concentration measured within the inlets around Victoria Lake (water samples unfiltered) from July 1997-June 1998). Data collected by the researcher and analyzed by Rand Water. g) Ortho-phosphates: Phosphorus is usually found in surface waters in the form of ortho-phosphate (Ellis, 1989). Phosphate is not toxic, but is an important parameter because it provides nutrition for algae and is indicative of pollution from detergents, fertilizers and sewage (Kempster, eta1.,1980). Natural sources of inorganic phosphorus include the weathering of rocks and the subsequent leaching of phosphate salts into the surface waters, in addition to the decomposition of organic matter. Ortho-phosphate concentrations measured for the inflows around Victoria Lake exceeded the limitation set by the South African Water Quality Guidelines for the specific tropic status of the system (eutrophic). The highest concentration was measured at site 6 (5.0mg/1)(see figure 23A). This site is actually the

61 phosphates measuredatsite4(22.0mg/1).Thesehighlevelsmaybeduetoindustrialand domestic discharge(SouthAfricanWaterQualityGuidelines(Volume2&7),1996), since thisinletdrainanindustrialandresidentialarea. Figure 23B(seetable26,Appendix4)showsveryhighconcentrationsofortho- 0.02 mg/1).. ortho-phosphate levelsmeasuredatVictoriaLakeforthestudyperiodwere(<0.02mg/1- carefully monitoredsincestudiesdonebySaunders,1997,revealedthattheaverage caused byalocalincidentoritcanevenbereleasedsedimentItshouldthus however changetheequilibriumandwillleadtoainnaturalstructure the shortterm.Acceleratedproductionduetohumaninducednutrientenrichment, functioning ofthebioticcommunities(Dallas&Day,1993;Ellis,1989;Hellawell,1986; with organicmaterialandbecomeobliterated.Thesystemisnormallyinequilibriumover unproductive tobetternourished,morehighlyproductivesystems,whichultimatelyfill rise toalevel,whichwillchangethetrophicstatusofsystem.Itiswellknownthat present withinthelake.Itisundesirabletoallowinorganicphosphorusconcentrations South AfricanWaterQualityGuidelines(Volume2&7),1996).Thesevaluescanalsobe lakes agenaturally,theybecomemoreenrichedandprogressfromrelatively outflow oftheVictoriaLake.Thismeansthatgreatamountsortho-phosphatesare

Ortho-phosphates mg/I) 4.5- 4.0- 5.0 - 3.0- 3.5- 2.0 - 2.5- 0.0 0.5- 1.5- 1.0- 7/97 8/979/9810/9811/9812/971/982/983/984/985/986/98 Time I I —0— Site3 Site 1 Site 4&5 Site 6 62 B) Council, B)DatacollectedbytheresearcherandanalyzedRandWater. (samples unfiltered)fromJuly1997-June1998.A)DatacollectedandreceivedGermiston Figure 23.OrthophosphateconcentrationmeasuredwithinthemajorinletsaroundVctoriaLake concentrations measuredwithintheinletsaroundVictoriaLakerangedfrom<20mg/1to (Hellawel1,1986). TheSouthAfricanwaterqualityguidelinesusedinthisstudydonot h) Sodium: entirely asamajorcontributortototaldissolvedsolids(Dallas&Day,1993). specify anytarget,chronicoracuteeffectvaluesforsodium.Mostofthesodium Sodium ismostprobablytheleasttoxicmetalpresentinaquaticenvironment June 1998.Datareceivedfrom GermistonCouncil. Figure 24.Sodiumconcentration measuredwithintheinletsaroundVictoriaLake fromJuly1997- 160 mg/1(site4&5)(seefigure24).Sodium'seffectontheaquaticsystemsarealmost Sodium ( Na mg/I) 100- 120- 140- 160- /I)

20- 40- (mg

60- tes 80- Orto-phoso ha 0– 22 - 20- 18- 14- 16- 12- 10- 6- 4- 8- 2- 0- 7/97 8/979/9710/97.11/9712/971/982/983/984/985/986/98 7/97 8/979/9710/9711/9712/971/982/983/984/985/986/98 / I /

. 11 I 1 1 1 Time Time I I I I -0- – Site4&5 ---a-- --9- --o — 0— — - Site3 -Acute effectvalue Site 6 Site 1 Site3 Site5 Site6 Site 2 Site 1 Site 4 63 i) Sulphate: Sulphur in water largely occurs as the sulphate (SO4 2') ion. The South African water quality guidelines used in this study do not specify any target, chronic or acute effect values for sulphate. Sulphate concentrations normally range between 10 and 80 mg/1 (Canadian water quality guidelines,1992). Levels of sulphate measured within the inlets around Victoria Lake were much higher, ranging between 9.0 mg/1 and 360 mg/1 (see figure 25, table 28, Appendix 4).The highest levels were measured at site 1 (360 mg/1) and site 2 (277 mg/1).These higher levels are typical of pollution from mining activity. Sources of sulphate within the inlets can be due to leachate from mine dumps (Hellawel1,1986) in the vicinity, degradation of organic matter in sediments, especially at site 1 were large amounts of algae were present, and the release from industrial effluents, especially metal working industries (Canadian water quality guidelines,1992).

400- --D-- Site 1 350-

/I) Site 2 300- mg

4 --- Site 3

O 250-

S Site 4 ( 200- te Site 5

ha 150-

lp -1:1- Site 6 100- Su 50-

II I III I III I I 7/97 8/97 9/97 10/9711/9712/97 1/98 2/98 3/98 4/98 5/98 6/98 Time

Figure 28. Sulphate concentration measured within the inlets around Victoria Lake (water samples unfiltered) from July 1997-June 1998. Data collected by researcher and analyzed by Rand Water.

2.4 Trace Metals: a) Aluminum: Aluminum is a strongly hydrolyzing metal and is relatively insoluble in the neutral pH range. Under acidic (pH<6) or alkaline (pH>8) conditions, or in the presence of complexing ligands, elevated concentrations may be mobilized to the aquatic environment (South African Water Quality Guidelines (Volume 2 &7), 1996). Aluminum is described as a "non-critical" element, though there is growing concern over effects of

64 elevated concentration of aluminum in the environment, primarily that mobilized as a result of acid mine drainage and acid precipitation (Dallas &Day, 1993; South African Water Quality Guidelines (Volume 2 &7), 1996). ). Most of the values measured within the inlets around Victoria Lake fell within the acute effect value (0.1 mg/1) set by South African Water Quality Guidelines, 1996 (see figure 29A & B, table 1, Appendix 3; tables 2 & 3 Appendix 4 ).The water samples that were not filtered indicated that higher levels of aluminum were present. This means that aluminum has been present in the from of suspended solids. The highest value measured for unfiltered samples was 2.8 mg A1/1 at site 5, while the highest value measured for filtered samples was 1.0 mg A1/1 at site 4. The high aluminum values are probably due to seepage and run off from the mining area since aluminum is found in soluble forms mainly in acid mine drainage (South African Water Quality Guidelines, 1996).

2.8 A) 2.6 -D- Site 1

/ 2.4 2.2 Site 2 2.0 l mg Site 3

A 1.8 ( 1.6 Site 4 1.4 1.2 inum 0-- Site 5 1.0 m 0.8 a- Site 6

Alu 0.6 Acute effect value 0.4 0.2 0.0 Chronic effect value

111111111111 7/97 8/97 9/97 10/9711/9712/97 1/98 2/98 3/98 4/98 5/98 6/98 Time

1.0 B) 0.9 -D-- Site 1

/I) 0.8 -•- Site 2 0.7 Site 3

Al mg 0.6 ( Site 4 0.5

inum 0.4 Site 5 0.3 -0-- Site 6

Alum 0.2 Acute effect value 0.1 hronic effect value 0.0

IIIIIIIIIIII 7/97 8/97 9/97 10/9711/9712/97 1/98 2/98 3/98 4/98 5/98 6/98 Time Figure 29. Concentration Aluminum within the inlets around Victoria Lake from July 1997-June 1998, A)Water samples unfiltered, B) Water samples filtered. Data collected by the researcher and analyzed by RAU, Department of Chemistry & Rand Water.

65 up topH9.0isinthedivalentcationform(Cd Cadmium isametalelementwhichhighlytoxictomarineandfreshwateraquaticlife b) Cadmium: due totheformationofcadmiumhydroxide(SouthAfricanWaterQualityGuidelines, (South AfricanWaterQualityGuidelines,1996).Mostofthecadmiumfoundinwaters Results showedthatthecadmiumvaluesmeasuredbyGermistonCouncilatinflows limits oftheavailableanalyticalmethod,buttheystillmaybehighenoughtoproduce cadmium presentinthewaterareoftenconcentrationsthatbelowdetection surrounding VictoriaLakewerezero(seefigure30A).Thismightbebecausethe A) adverse effectsonaquaticorganismsofVictoriaLake(He B) 1996). 1994; Wilhm&Dorris,1968). 0 65 E z E E 6)

Cadn ium (Cd mg/I) 0.0040 0.0000 0.0035 0.0005 0.0010 0.0015 0.0020 0.0025 0.0030 0.00 0.01 0.02 0.03 0.04 0.10 0.05 0.06 0.07 0.08 0.09 7/97 8/979/9710/9711/9712/971/982/983/984/98 7/97 8/979/9710/9711/9712/971/982/98 Time Time 3/98 4/985/986/98 2+ ), whilesolubilitydecreaseabovepH9.0 5/98 6/98 i ath, 1993;Prosi,1979;Patrick, —0------6 —a- — - -4 t -- — Site1 9 Acute effectvalue 1 -- Site6 — Site6 Site4 Site 5 Site 3 Site 2 Site4&5 Acute effectvalue Target effectvalue Chronic effectvalue Site 3 Site . 1 66 not consideredtobeaparticularly eco-toxictracemetal(Dallas&Day, 1993).TheSouth toxicity andavailabilityintheenvironmentare low,however,andsocobaltisgenerally metal intotheinletsbycertainelectroplatingindustriesinareaandpossiblyalso July 1997-June1998.A)DatacollectedandreceivedfromGermistonCouncil,B)by C) Although cobaltisanessentialmicro-nutrient,it isalsotoxicinfairlysmallquantities.Its waters ofVictoriaLakerangedfrom0.004mg/1-0.005 mg/1(Saunders,1997). Previous studiesdoneshowedthattheconcentration cadmiumpresentinthesurface The resultspresentedhere,howeverdoesnot implylargescalecadmiumpollution. Cd formediumhardwater)suggestedbySouthAfricanWaterQualityGuidelines,1996. ESKOM, whichissituateatsite3.Thesevaluesexceedtheacuteeffectvalue(0.006mg/1 were 0.04mg/Icadmiumforsite4(watersamplesunfiltered)and0.02mg/1 on thegraphas0.1mg/1.RandWaterhowever,madeuseofadetectionlimit0.05mg/1 detection limitof0.1mg/1(seetable4,Appendix3).Theseresultshoweverwereplotted Results analyzedbyRAU,DepartmentofChemistry,werealsomostlyunderthe Rand Water(watersamplesfiltered). Figure 30.CadmiumconcentrationmeasuredwithinthemajorinletsaroundVictoriaLakefrom c) Cobalt: site 3(watersamplesfiltered).Thismayhaveresultedfromanincreasedinputofthis (see table5&6,Appendix4).Thehighestvaluesmeasuredbesidesthedetectionlimits unfiltered), C)DatacollectedbytheresearcherandanalyzedRAU,DepartmentofChemistry& researcher andanalyzedbyRAU,DepartmentofChemistry&RandWater(watersamples

Cadn iu m (Cd mg/I) 0.10 0.09 0.08 0.07 0.06 0.05 0.04 0.03 0.02 0.01 0.00 7/97 IIIIIIIIIIII 8/97 9/97 10/9711/9712/97 Time 1/98 2/98 3/98 4/98 5/98 6/98 --.-- Site2 —0 — 0-- -- Acute effectvalue Site5 Site6 Site 1 Site 3 Site 4 67

African water quality guidelines used in this study do not specify any target, chronic or acute effect values for cobalt. 0.40- 0.38- Site A) 0.36- 0.34 - 0.32- Site 2 /I) 0.30- 0.28- Site 3 0.26- —9-- mg 0.24- 0.22- Co --- Site 4 0.20

lt ( lt 0.18 0.16 0— Site 5 ba 0.14 0.12 Site 6 Co 0.10 0.08 0.06 0.04 0.02- 0.00-

7/97 8/97 9/97 10/9711/9712/97 1/98 2/98 3/98 4/98 5/98 6/98 Time

0.39- —0-- Site 1 B) 0.36-

0.33- Site 2

/I) 0.30 —9— Site 3 0.27 mg 0.24 —9-- Site 4

Co 0.21-

lt ( 0.18- —0,— Site 5 0.15- ba Site 6 0.12- —0— Co 0.09 0.06 0.03- 0.00-

7/97 8/97 9/97 10/9711/9712/97 1/98 2/98 3/98 4/98 5/98 6/98 Time _ Figure 31. Cobalt concentration within the inlets around Victoria Lake from July 1997-June 1998, A)Water samples unfiltered, B) Water samples filtered. Data collected by the researcher and analyzed by RAU, Department of Chemistry & Rand Water.

A few high values were measured at sites 4 & 5 (see figure 31A & B, table 5, Appendix 3; table 12 &13 Appendix 4). Much of the cobalt within the inlets surrounding Victoria Lake is likely to arise from the escape of contaminated effluents from nearby industries and from run off and seepage form the mines in the area (Dallas & Day, 1993). Forstner & Wittmann, 1981, measured levels as high as 0.27 mg/1 Co in effluents from gold mining waste on the East Rand .

68 d)Copper: Copper is one of the world's most widely used metals. Although copper occurs naturally in most waters, it is regarded as potentially hazardous by the United States Environmental Protection Agency (South African Water Quality Guidelines, 1996). 1.2-, A) 1.1- Site 1

1.0- -0- /I) Site 3 0.9- 0.8- Site 4&5 mg 0.7- Cu --0- Site 6 ( 0.6- r

e 0.5- 0.4-

Copp 0.3- Acute effect value 0.2- 0.1-

0.0-i .r-- L Time 7/97 8/97 9/97 10/9711/9712/97 1/98 2/98.3/98 4/98 5/98 6/98

B) 2.6 2.4 Site 1 2.2

/I) -4- Site 2 2.0 1.8 °-- Site 3 mg 1.6 Cu -4- Site 4

( 1.4

er 1.2 Site 5 1.0 0.8 Site 6 Copp 0.6 is Acute effect value 0.4 0.2 0.0 Time 7/97 8/97 9/97 10/9711/9712/97 1/98 2/98 3/98 4/98 5/98 6/98 - - - C) 2.0 1.9 - - Site 1 1.8 D

1.7 1.6 Site 2 /I) 1.5 1.4 Site 3

mg 1.3 1.2 1.1 Site 4

(Cu 1.0

er 0.9 0.8 Site 5 0.7 0.6 -0-- Site 6

Copp 0.5 0.4 Acute effect value 0.3 0.2 0.1 0.0

111111111 111 Time 7/97 8/97 9/97 10/9711/9712/97 1/98 2/98 3/98 4/98 5/98 6/98 Figure 32. Copper concentration measured within the major inlets around Victoria Lake from July 1997-June 1998. A) Data collected and received from Germiston Council, B) Data collected by researcher and analyzed by RAU, Department of Chemistry & Rand Water (water samples unfiltered, C) Data collected by the researcher and analyzed by RAU, Department of Chemistry & Rand Water (water samples filtered).

69 Copper concentrations measured by Germiston Council within the inflows around Victoria Lake showed elevated levels of copper concentrations (see figure 32A). The South African Water Quality Guidelines (Volume 7) specified that as little as 0.0075 mg/1 copper is enough to cause an acute toxic effect. Site 4 & 5 had copper concentrations as high as 1.1 mg/I copper which is considered very unsafe (Dallas & Day, 1993; Hellawell, 1986; South African Water Quality Guidelines, 1996).

Results analyzed by RAU, Department of Chemistry and Rand Water (see figures 32B &C, table 3, Appendix 3, tables 14 &15, Appendix 4) indicate that distressing high levels of copper were also measured at sites 4 & 5.Some high values were also measured at site 1. The unfiltered samples had slightly higher values than the filtered samples which indicates that some of the copper were present as suspended solids. These higher particulate concentrations are not unusual as copper is transported in water mainly as solid from, i.e. bound to suspended matter (De Groot & Allersma, 1973). The main sources of copper at sites 4 & 5 is probably liquid effluents released from the surrounding industrial area , or it could be due to sewage treatment plant effluents since sewage were detected at these sites (South African Water Quality Guidelines, 1996). Run off from the use of copper fungicides and pesticides in the treatment of soil could also be a source of copper (South African Water Quality Guidelines, 1996) at site 1 since it is situated at a golf course. e) Chromium: Chromium is relatively scarce as a metal, and occurrence and amounts thereof in aquatic ecosystems are usually very low (South African Water Quality Guidelines, 1996). Chromium is one of the least toxic of the trace metals at low concentrations and is in fact essential for fat and carbohydrate metabolism in mammals. It occurs in several oxidation states (+2 to +6), of which chromium (VI) is the most toxic.

70 A) 2.4 2.2- Site 1

/I) 2.0- —0— Site 3 1.8-

mg 1.6- --c' – Site 4&5 Cr 1.4- ( Site 6 1.2- 1.0- Acute effect value m iu m

o 0.8- 0.6- Chr 0.4- 0.2 ronic effect value 0.0 Target effect value II 7/97 8/97 9/97 10/9711/9712/97 1/98 2/98 3/98 4/98 5/98 6/98 Time

0.10- Site 1

. 0.09-

B) I) / 0.08 Site 2

mg 0.07- Site 3

Cr 0.06 -

( Site 4

m 0.05-'

iu Site 5 0.04- m 0.03- —a— Site 6

Chro 0.02- Chronic effect value 0.01-w Target effect value 0.00-1

it 7/97 8/97 9/97 10/9711/9712/97 1/98 2/98 3/98 4/98 5/98 6/98 Time

C) 0.10- Site 1 0.09-

/ Site 2 0.08-

mg 0.07- Site 3

Cr 0.06 Site 4 (

m 0.05-

iu Site 5 0.04- m 0.03- —0-- Site 6 Chronic effect value

Chro 0.02-

0.01 Target effect value 0.00-

I I I I I I I I I I I 7/97 8/97 9/97 10/9711/9712/97 1/98 2/98 3/98 4/98 5/98 6/98 Time

Figure 33. Chromium concentration measured within the major inlets around Victoria Lake from July 1997-June 1998. A) Data collected and received from Germiston Council, B) Data collected by researcher and analyzed by RAU, Department of Chemistry & Rand Water (water samples unfiltered, C) Data collected by the researcher and analyzed by RAU, Department of Chemistry & Rand Water (water samples filtered).

71; Concentrations of chromium measured by Germiston Council within the inlets around Victoria Lake showed three measurements that exceeded the acute effect value. They were measure at site 1 (0.4 mg/1), site 4 & 5 (2.2 mg/I) and site 6 (0.3 mg/1)(see figure 33A).

Analysis done by RAU, Department of Chemistry (see figure 33, table 6, Appendix 3) and Rand Water (see figure 33, tables 10 &11, Appendix 4) showed that most values were below the detection limits of 0.1 mg/1 (RAU, Department of Chemistry), and 0.05 mg/1 (Rand Water). Chromium values that were not under the detection limit could be classified as chronic effect values (0.014 - 0.2 mg/1) (South African Water Quality Guidelines, 1996).The presence of chromium is probably due to industrial run off. e) Iron:

Iron is the most abundant element in the earth's crust and may be present in natural waters in varying quantities depending on the geology of the area and other chemical properties of the water body (South African Water Quality Guidelines, 1996). Iron present in water is however generally present in concentrations less than 0.5 mg/1 (Canadian water quality guidelines,1992). The geology of Victoria Lake consists predominantly of the Witwatersrand gold deposits due to mining activities. Gold deposits, pyrite (FeS2), is the most common ore mineral and is often found in close association with acid mine drainage. Mine drainage has however been diverted away from the lake (Schoonbee, et. al., 1995). Surface run off from old mine dumps however still enters the inlets around the lake. It is thus expected that amounts of iron will be present in the waters of the inlets. High levels of iron were measured at sites 4 &5 by Germiston Council (7.0 mg/1)(see figure 34A) during October 1997. Data received from RAU, Department of Chemistry and Rand Water confirmed that very high levels of iron were present at site 5 (21 mg/1 iron, samples unfiltered (figure 34B) and 13 mg/1 iron, samples filtered (figure 34C)) during November 1997 (see table 7, Appendix 3, table 16 & 17, Appendix 4). It seemed as if effluents containing iron escaped from industries in the area via surface run off. Saunders, 1997, measured the concentration of iron of the surface waters of Victoria Lake and found that it ranged from 0.125 mg/1 to 0.646 mg/l.

The concentration iron measured within the inlet waters were exceptionally high in comparison to the water of the lake. 7.0- 6.5- X —0 — Site 1 A) 6.0- II I I 0-- Site 3

5.5- / I /I) 5.0- Site 4&5 /I 4.5- I I mg 4.0- —9-- Site 6 I I

Fe 3.5 I I ( 3.0- n I 1 rt 2.5- I I . / \ Iro 2.0- I I „Ix, / \ ..01 I ., . / 1.5- „- . \ L-' e v 0.5- 0.0-

7/97 8/97 9/97 10/9711/9712/97 1/98 2/98 3/98 4/98 5/98 6/98 Time B) 21- 20- 19- —0— Site 1 18- 17-

Site 2 16-

/I) 15- 14- Site 3 13-

mg 12- 11- --°-- Site 4 Fe 10- ( 9- Site 5 on 7- Ir 6- —13-- Site 6 5 - 4 - 3 - 2 - 1- , 0 - --o---=7,

I I I I I I I I I I I I 7/97 8/97 9/97 10/9711/9712/97 1/98 2/98 3/98 4/98 5/98 6/98 C) Time

13- --0-- Site 1 12- 11- Site 2 10- I) / 9- Site 3 ! 8- mg 7- Site 4 Fe

( 6- Site 5 n 5 o

Ir 4 10-- Site 6 3 2 1- 0-

II II 7/97 8/97 9/97 10/9711/9712/97 1/98 2/98 3/98 4/98 5/98 6/98 Time Figure 34. Iron concentration measured within the major inlets around Victoria Lake from July 1997-June 1998. A) Data collected and received from Germiston Council, B) Data collected by researcher and analyzed by RAU, Department of Chemistry & Rand Water (water samples unfiltered, C) Data collected by the researcher and analyzed by RAU, Department of Chemistry & Rand Water (water samples filtered).

73 g) Manganese: Manganese is the eigth most abundant metal in nature, and occurs in a number of ores. Manganese is an essential micro-nutrient for plants and animals. High concentrations of manganese however is toxic, and may cause disturbances in various metabolic pathways (South African Water it uali Guidelines, 1996). 19 18 —G-- Site 1 17 FP 16 Site 2 c 15 14 13 Site 3 2 12 11 10 Site 4 9 C 8 Site 5 to 6 5 —0— Site 6 4 Acute effect value 3 2 Chronic effect value

Target effect value I I 7/97 8/97 9/97 10/9711/97 12/97 1/98 2/98 3/98 4/98 5/98 6/98 Time 22 —a— Site .1 20 Site 2 B) E 18 c 16 Site 3 14 a) 12 Site 4 10 Site 5 its Site 6 Acute effect value E 4 2 Chronic effect value

It I I i 7/97 8/97 9/97 10/9711/9712/97 1/98 2/98 3/98 4/98 5/98 6/98 Figure 35. Concentration iron measured within the major inlets around Victoria Lake from July 1997-June 1998. A) Data collected by researcher and analyzed by RAU, Department of Chemistry & Rand Water (water samples unfiltered, B) Data collected by the researcher and analyzed by RAU, Department of Chemistry & Rand Water (water samples filtered).

Manganese levels in the water of site 1, 4& 5 were significantly higher than the rest of the sites monitored (see figure 35, table 9, Appendix 3& table 20 & 21, Appendix 4).Most of these levels exceeded the limit set by South African Water quality Guidelines, 1996, for the acute effect value of 1.3 mg/1 manganese. Levels measured at site 1 were as high as 7 mg/1 manganese (figure 35A) for samples that has not been filtered and 8 mg/1 manganese (figure 35B) for samples that has been filtered. Manganese levels at site 4 were the highest, 20 mg/1 (figure 35A) for samples that have not been filtered and 22mg/1

74 (figure 35B) for samples that has been filtered. At site 5 manganese levels were as high as 15 mg/l. These high levels of manganese are probably released in the form of industrial discharge from steel and chemical industries (South African Water Quality Guidelines,1996) in the vicinity of the inlets. Levels of manganese concentrations of the surface waters of Victoria Lake measured by Saunders, 1997, were as high as 0.23 mg/l. These levels already exceeded the acute effect value set by the South African Water Quality Guidelines,1996. The high levels in the inlet waters will thus contribute to more elevated levels of manganese inside Victoria Lake. h) Nickel: Nickel is certainly toxic in small quantities (Dalas &Day, 1993). Nickel ions tend to be soluble at pH values <6.5. Above a pH .of 6.7 they mostly form insoluble nickel hydroxides. About half of the nickel present in most fresh waters is in the ionic form and about the other half in the form of stable organic complexes, many of which readily absorb onto clay particles (Dallas &Day, 1993). This explains why the levels of nickel measured for the filtered water samples were slightly less than the unfiltered water samples. The unfiltered water samples must have contained some suspended clay particles bound with nickel complexes. The South African water quality guidelines used in this study do not specify any target, chronic or acute effect values for nickel. High concentrations of nickel were measured by Germiston Council at sites 4 & 5, 4.3 mg/1, and at site 3, 0.9 mg/1 (see figure 36A). Data analyzed by RAU, Department of Chemistry and Rand Water also indicated that high concentrations of nickel were measured at site 5 (see figure 36B & C, table10, Appendix 3; tables 22 & 23, Appendix 4). This is probably due to industrial activities in the vicinity of this inlet. The concentration nickel present in the surface waters of Victoria Lake only varied between 0.03 mg/1 and 0.08 mg/1 (Saunders, 1997). This is far less than the amounts of nickel detected in the waters of the inlets.

75 B) C) Figure 36.Nickelconcentrationmeasuredwithinthe majorinletsaroundVictoriaLakefromJuly Rand Water(watersamples filtered). unfiltered, C)Datacollected bytheresearcherandanalyzedRAU,Department ofChemistry& researcher andanalyzed byRAU,DepartmentofChemistry&RandWater (watersamples 1997-June 1998.A)Datacollectedandreceivedfrom GermistonCouncil,B)Datacollectedby

N ic ke l ( Ni mg/I) Nicke l ( N i mg/I) Nic ke l ( Ni mg/I) 4.0- 4.5- 5.0- 3.5- 2.5- 3.0- 0.5 2.0 0.0 0.8- 0.9- 1.0 1.5 0.2- 0.3- 0.4- 0.5- 0.6- 0.7 - 0.0- 0.1- 1.0- 1.1- 0.9- 0.8- 0.3- 0.4- 0.5- 0.6- 0.7- 1.0-- 0.1- 0.2- 0.0- 7/97 8/979/9710/9711/9712/971/982/983/984/985/986/98 7/97 8/979/9710/9711/9712/971/982/983/984/985/986/98 7/97 8/979/9716/9711/9712/971/982/983/984/985/986/98 I I III] I I I I I I 1 I k I I I Time Time ;II 1111111 Tima It II • -0-- -9- -a- Site1 -0- - -0- Site6 0 -- 0--- Site5 Site6 Site3 Site6 Site5 Site 1 Site 4&5 Site 3 Site 2 Site 4 Site 2 Site 1 Site 4 Site 3 76 i) Lead:

Levels of dissolved lead in water are generally low since this metal is not readily soluble but becomes rapidly fixed to particulate matter in the receiving water body (De Groot & Allersma, 1973). Lead's solubility is influenced by alkalinity and hardness, with higher solubility present in soft water (Mason,1991). Mean global lead concentrations range from 0.001 mg/1 to 0.01 mg/1 but the levels of this metal measured within the inlets around Victoria Lake were higher. Some of the concentration lead values measured at Victoria Lake exceed both the target -and chronic effect values (see figure 37) (South African Water Quality Guidelines (Volume 7), 1996). Germiston Council measured levels as high as 0.2 mg/1 lead at site 4&5. Other sites with high levels were site 1 '(0,1 mg/1) and site 3 (0,1 mg/1). Results received from RAU, Department of Chemistry and Rand water stated that higher levels of zinc were present in the waters of the inlets(figure 37B & C). The highest reading was 1.3 mg/1 measured at site 5. High values were also measured at site 1 and 4. These values of 0.3 mg/1 lead are not certain though, since they were below the detection limit of 0.3 mg/1 lead (see table 8, Appendix 3; tables 18&19, Appendix 4). Most of the lead entering the aquatic systems is associated with suspended sediments, while lead in dissolved phase is usually complexed by organic ligands. Other sources of lead include precipitation, fallout of lead dust, street runoff since lead is a common additive in the petrol used in South Africa, industrial and municipal waste including steel works and electroplating industries near the lake, and mining, milling and smelting of lead and metals associated with lead.

A) 0.22- 0.20- Site 1 0.18- —0-- Site 3 /I) 0.16- Site 4&5 mg 0.14- 0.12-

Pb —0— Site 6 (

0.10- d 0.08-

Lea 0.06- Pb Acute effect value 0.04- 0.02- 0.00-i

IFI 11 7/97 8/97 9/97 10/9711/97 12/97 1/98 2/98 3/98 4/98 5/98 6/98 Time

77 1.3 1.2 -0- Site 1 B) 1.1 -0- Site 2 1.0 /I) 0.9 Site 3 0.8

b mg 0.7 Site 4 P 0.6

d ( -0-- Site 5 0.5 0.4 Lea -10- Site 6 0.3 Acute effect value 0.2 0.1 0.0

7/97 8/97 9/97 10/9711/9712/97 1/98 2/98 3/98 4/98 5/98 6/98 Time

0.30 0.28 Site 1 C) 0.26 0.24 Site 2

/I) 0.22 0.20 Site 3 0.18 b mg 0.16 Site 4 P 0.14

d ( 0.12 Site 5 0.10 Lea 0.08 -0- Site 6 0.06 Acute effect value 0.04 0.02 0.00

7/97 8/97 9/97 10/9711/9712/97 1/98 2/98 3/98 4/98 5/98 6/98 Time Figure 37. Concentration lead measured within the major inlets around Victoria Lake from July 1997-June 1998. A) Data collected and received from Germiston Council, B) Data collected by researcher and analyzed by RAU, Department of Chemistry & Rand Water (water samples unfiltered, C) Data collected by the researcher and analyzed by RAU, Department of Chemistry & Rand Water (water samples filtered). j)Zinc:

Zinc is an essential micro-nutrient for all organisms. In aquatic ecosystems zinc(II) ion is toxic to fish and aquatic organisms at relatively low concentrations (South African Water Quality Guidelines (Volume 7), 1996). The greatest dissolved zinc concentrations will occur in water with low pH, low alkalinity and high ionic strength. This might explain the high values of zinc measured at sites 1, 4 & 5 (see figure 38). The waters of these sites proved to have a great amount of ions dissolved in it (see conductivity). The highest value of zinc measured by Germiston Council was at site 4 &5 (4.8 mg/1)(see figure 38A). Site 3 had the second highest concentration of zinc measured by Germiston Council (3.5 mg/1). Results received from RAU, Department of Chemistry and Rand

78 Water stated that the highest values of zinc were measured at sites 1,4 &5 (see figure 38B & C, table 11, Appendix 3; tables 29 & 30, Appendix 4). These values did not satisfy the target water quality range. Chronic and acute toxicity effects will occur because the acute effect value has been exceeded (South African Water Quality Guidelines (Volume 7), 1996).Zinc can enter the aquatic system through both natural processes such as weathering and erosion, and through industrial activity, like metal galvanizing, dye manufacturing, paints and cosmetics, pharmaceuticals, fertilizers and insecticides (South African Water Quality Guidelines (Volume 7), 1996).

5.0 A) Site 1 4.5

4.0 -0— Site 3

/I) 3.5 Site 4&5 3.0 mg Site 6

Zn 2.5 ( 2.0 inc

Z 1.5 Acute effect value 1.0

0.5 0.0

r 1 I 7/97 8/97 9/97 10/9711/9712/97 1/98 2/98 3/98 4/98 5/98 6/98 Time

B) 12 11 Site 1 10 Site 2 9 /I) 8 Site 3

mg 7 Site 4 Zn

c( 5 Site 5 in

Z 4 2 "—D—ACSutitee eff6ect value 1 .411411kb.. SA

I I I I 1 7/97 8/97 9/97 10/9711/9712/97 1/98 2/98 3/98 4/98 5/98 6/98

Time

79 12 r----- Site 1 C) 11 -- 10 Site 2 ..— 9 -a) 8 Site 3 E 7 Site 4 N 6 -, -; Site 5 c

—a-- Site 6 Acute effect value

Ii IIIIIIIII 1 7/97 8/97 9/97 10/97 11/97 12/97 1/98 2/98 3/98 4/98 5/98 6/98 Time

Figure 38. Zinc concentration measured within the major inlets around Victoria Lake from July 1997-June 1998. A) Data collected and received from Germiston Council, B) Data collected by researcher and analyzed by RAU, Department of Chemistry & Rand Water (water samples unfiltered, C) Data collected by the researcher and analyzed by RAU, Department of Chemistry & Rand Water (water samples filtered).

3.Miro-biological factors. a) Conforms and E. coli: Total coliform bacteria measured within the inlets around Victoria Lake had values as high as 300 000 counts/100m1 at sites 1, 4&5, and a count of 186 000/100m1 at site 1 (see figure 39). This coliform count exceeds the limits set by the South African Water Quality Guidelines (Volume 2); 1996. As coliform counts increase above this limit, the risk of contracting gastrointestinal illness as a result of full contact recreation increases. The volume of water which needs to be ingested in order to cause adverse effects decreases as the coliforms increase (South African Water Quality Guidelines (Volume 2), 1996).

E. coli counts range from 0 to 300 000 counts per 100 ml (see figure 40). These counts exceeded the limits as well, and pose a major health risk. The high E. coli counts indicate that the major source of pollution must be of faecal origin (South African Water Quality Guidelines (Volume 2), 1996).

80 Most ofthewaterquality constituentsthathavebeencomparedwith thewaterquality to bethemostpollutedinletsandtheyshould closelymonitoredinfuture. pollutants ofthewatersinletsaresummarized inAppendix1.Sites1,4and5seem criteria exceededtheacute effectvaluesgivenbytheSouthAfrican WaterQuality comparison tothesurfacewatersoflake.The majorsourcesofpollutionandpossible In generalitseemsasifthewatersofinlets around VictoriaLakearemorepollutedin Council). Guidelines. Afarbetter interpretationofthemeaningvalues measuredfor 7. CONCLUSION. (Germiston Council). Figure 40. Figure 39.ColiformconcentrationmeasuredwithinthemajorinletsaroundVictoriaLake Coliforms /(100m 1) E. coli 1(1 00m1) 275000 300000 250000 200000 225000 175000 150000 100000 125000 75000 50000 25000 250000 275000 300000 200000 225000 125000 150000 175000 100000 50000 75000 25000 0 E. coli 0 7/97 8/979/9710/9711/9712/97 7/97 Ma a 11111111 concentration measuredwithinthemajorinletsaroundVictoriaLake(Germiston 8/97 9/97 10/9711/9712/97 Time Time 1/98 /8 2/98 1/98 a 2/98 Jail 3/98 3/98 1111 4/98 4/98 5/98 5/98 6/98 6/98 a

--*– Site4&5 — c --- Site 1 Site 3 Site 6 Acute effectvalue Site4 Site 1 Site 3 Site 2 Acute effectvalue the 81 various constituents can be obtained if they are compared with more than one set of criteria. Appendix 2 contains criteria set by Kempster, et. a/.,1982; Kiihn,1991 and Canadian Water Quality Guidelines, 1987.

8. SYNTHESIS AND RECOMMENDATIONS.

Waste is 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 development should take place in terms of sustainable development. Sustainable development means meeting the basic needs of all and extending to all the opportunity to satisfy their aspirations for a better life. Yet it also implies acceptance of consumption standards that are within the bounds of ecological possibility (Hugo, et al., 1997).

There are a number of general methods that may be used to manage Victoria Lake as an environmental resource base. According to the Department of Environmental Affairs and Tourism (South Africa, 1994) the following methods may be used:

• Regulation and prohibition This is the traditional command -and -control method. It is usually the best approach where monitoring and enforcement costs are not too high, for example there is only one source of pollution (Department of Environmental Affairs and Tourism, South Africa, 1994). One approach to controlling environmental pollution and over-exploitation of resources is to set standards or prescribe certain actions. To control pollution, for example, the council can either set a permissible level of emissions (e.g. x units per hour), or require certain devices to be used to minimize emissions (Fuggle & Rabie, 1992). The South African Water Quality Guidelines has specifically been designed for this purpose. It is advisable to use more than one set of standards for a far better perspective, another set of such standards that can be used is the Canadian Standards (see appendix 2).

82 While direct controls can be effective in implementing policy, there are several difficulties with this approach. The council has usually inadequate information to establish cost-effective controls (the polluter or resource user is likely to have better information but is unlikely to provide accurate data). In addition, blanket regulations mandating specific control measures are inefficient as each case is different, the most efficient action would vary from case to case, yet tailoring regulations to fit each case could be prohibitively costly. Another major difficulty is that monitoring and enforcement of regulations can be expensive and unpopular tax increases may be necessary to fund adequate enforcement measures (Fuggle & Rabie, 1992).

Provision of information Providing information about the environment leads to a better understanding of the environment and makes users aware of their actions relative to the environment. When people understand a situation, they will be more strongly motivated to comply with requirements (Department of Environmental Affairs and Tourism, South Africa, 1994). Germiston Council can circulate information booklets with all the recent information on the water quality of Victoria Lake and the major inlets to all the industries and mine in the surrounding area.

Strengthening of property rights A lack of clearly defined property rights, especially with regard to less tangible environmental resources like water and air, is a major deterrent to the market and impacts negatively on environmental resource management. If nobody is specifically liable, no one will take responsibility (Department of Environmental Affairs and Tourism, South Africa, 1994). Germiston Council must strengthen and clearly define property rights with special reference to the major inlets in order to determine responsibility for pollution.

Economic instruments Another approach to influencing environmental behavior and promoting the economically efficient and equitable use of natural resources is application of economic incentives (Department of Environmental Affairs and Tourism, South Africa, 1994).

83 Economic incentives attempt to correct market signals which lead to environmentally damaging activities, and have a number of advantages over regulatory or command-and- control approaches referred to in the previous section. Economic incentives attach a cost- determined by the authorities or in the market-to the polluting activity. The cost is related to damages suffered as a consequence of the externalities resulting from the acting party's activities and should result in environmental quality meeting the goals set by environmental authorities. There are a number of different and innovative economic incentives suited to various situations, some of which will be discussed individually below (Fuggle & Rabie, 1992).

a Pollution charges: A pollution charge serves to attach a price to the previously free use of the natural resource as a sink for waste, or the use of a resource in excess of regenerative capacity. Charges have the advantage of being both equitable- the polluter pays- and economically efficient: control is achieved at the lowest cost to society, so freeing resources for other productive uses. In contrast to regulation, where a certain amount of pollution is allowed and is free up to a point at which the standard applies, a charge ensures that all pollution carries a price- the polluter pays for all damage that occurs (Fuggle & Rabie, 1992). Such pollution charges can strengthen Germiston Council's environmental management as more capital will be available for further environmental use. Pollution charges require strict control.

u Subsidies: Through the payment of a per unit subsidy by the environmental authority to the polluter for abatement theoretically leads to the same outcome as the imposition of a charge, it has certain disadvantages. If the mill receives a subsidy for unit reductions in discharges, it will decrease pollution to the point where the cost of abatement equals the subsidy. After this point, it will prefer to pollute because the subsidy will be less than the cost of abatement. Subsidies are generally financed from general taxation and this spread the costs for abatement across to all taxpayers, rather than returning it to the polluter (Fuggle & Rabie, 1992). In South

84 Africa the payment of per unit subsidies will probably be impractical since tax money has to be used to rather dissolved more important social issues such as housing, education and proper sanitation. n=>Marketable permits: The environmental authority determines the quality goal it wishes to achieve in terms of the assimilative capacity of the resource. This will be equivalent to that desired under a regulatory of charge system. It then makes permits available for damage allowed in terms of its environmental goal. Because permits set a limit to allowable aggregate discharges, they are preferable to charge where the outcome is uncertain. The effect of marketable permits on the actions of the acting party, and hence on environmental quality, will be similar to that of an effluent charge. Those who can reduce their discharges cheaply-where the cost is less than the market price of the permit-will do so, and the environmental goal will be met at minimum cost to society. Marketable permits are therefore economically efficient, and they are equitable because the polluter pays for the damage he causes (Fuggle & Rabie, 1992). u Environmental bonds: Environmental bonds as an instrument of control derive the traditional refundable deposit or "materials use fee". These fees act as an incentive for individuals to dispose of environmentally damaging resources in a socially desirable way. For example, in South Africa, refunds available on some glass bottles attempt to encourage recycling rather than littering. The fee should be set at which the bottle's return is profitable to the individual and the percentage rate of return is high. In countries where there is widespread poverty, the necessary fee is likely to be lower than in First World countries. An environmental bond is a sophisticated version of the "materials use fee". Its use is recommended where the environmental effects of production or consumption activities are unknown or uncertain in advance and where environmental damage is extremely difficult to ascertain-where rational decisions are misguided by informational deficiencies. Where effects are known and risks can be calculated, commercial insurance against future environmental damage could be sought. Examples of potential use include

85 the disposal of hazardous waste and the rehabilitation of open cast mines (Fuggle & Rabie, 1992). Germiston Council can consider environmental bonds as a solution for mine pollution. Rehabilitation of old mines can earn a fee from the Council. ag> Compensation: Although economic incentives have been shown, in terms of equity and efficiency and in other respects, to be preferable to regulation and the public sector provision, they are often perceived to place an unfair burden on poor communities. The imposition of charge or other froms of economic incentives will increase the cost of production of the economic unit for any quantity of product produced and consequently narrow the available profit margin. This will be absorbed by the entrepreneurs or shareholders or will be recouped via a price increase to consumers, some of whom are poor. Where cost-effective economic incentives are implemented which adversely effect some members of the society, the payment of compensation may be advisable for reasons of social equity and political expediency. But the amount that is needed and the manner in which it is paid can be very complex. An alternative to monetary compensation is "linked compensation" where the form of compensation relates directly to the type of damage suffered. For example, if the price of electricity rises due to imposition of an effluent charge, compensation could be provided to poor communities via a deduction on their electricity bills. This should not entail a substantial financial burden in South Africa, since poor communities use less percentage of electricity consumed.

The use of economic incentives to redirect individual choices distorted by institutional, informational or temporal deficiencies appears, in theory, to be superior to control by regulation. Since incentives act as an encouragement for point-source polluters to move towards a more equitable allocation of the costs of environmental damage, in that the polluter pays for not only his private costs but also the social damage caused as a result of his actions (Fuggle & Rabie, 1992).Germiston Council should however consider all the methods of managing Victoria Lake and the major inlets before choosing a single method. It might even be more practical to combine some of the managing methods.

86 • Environmental Management Systems Achieving sound environmental performance requires organizational commitment of each industry contributing to the pollution at the major inlets of Victoria Lake, to a systematic approach and to continual improvement of the environment. Therefore it is important to require of each industry contributing to the deterioration of the water quality within the major inlets and the water quality of Victoria Lake to develop environmental management systems.

An Environmental Management System provides order and consistency for these organizations and industries to address environmental concerns through the allocation of resources, assignment of responsibilities, and ongoing evaluation of practices, procedures and processes. Environmental management is an integral part of an organization's overall management system. The design of an EMS is an ongoing and interactive process. The structure, responsibilities, practices, procedures, processes and resources for implementing environmental policies, objectives and targets can be coordinated with the exiting efforts in other areas (e.g. operations, finance, quality, occupational health and safety) (Bosman, 1996; Cameron,1994; Lukas, 1997; ISO 14004:1996; ISO 14001:1996).

International Standards considers the elements of an EMS and provides practical advice on implementing or enhancing such a system. It also provides organizations with advice on how to effectively initiate, improve or sustain an environmental management system. Such a system is essential to an organization's ability to anticipate and meet its environmental objectives and to ensure ongoing compliance with national and/ or international requirements (Bosman, 1996; Cameron, 1994; ISO 14004:1996; ISO 14001:1996). Germiston Council should require such an environmental management system of all the industries that contribute to the pollution of the major inlets around Victoria Lake.

Industries can consider the following different uses of the EMS international standards

87 Using ISO 14001:1996, Environmental management systems- specification with guidance for use to achieve third-party certification/registration, or self-declaration of an organization's EMS. Using ISO 14004:1996, Environmental management systems-general guidelines on principles, systems and supporting techniques, or parts of it, to initiate and/or improve its EMS. It can also be used as a specification for second-party recognition between contracting parties, which may be suitable for some business relationships (Bosman, 1996; Cameron, 1994; ISO 14004:1996; ISO 14001:1996).

Figure 41 shows the basic approach for environmental management systems. It has been written to be applicable to all types of organizations and to accommodate diverse geographical, cultural, and social conditions. The success of the system depends on commitment from all levels and functions, especially form top management of involved industries. A system of this kind enables an organization to establish, and assess the effectiveness of, procedures to set an environmental policy and objectives, achieve conformance with them, and demonstrate such conformance to others.

Continual Evaluation

Environmental policy Management Review

Planning

Checking and corrective acting Implementing and operating

Figure 41. Environmental System Model (ISO 14004, 1996; ISO 14001,1996).

88 The EMS model follows the basic view of an organization which subscribes to the following principles: Principle 1- Commitment and Policy Principle 2- Planning Principle 3- Implementation Principle 4- Measurement and Evaluation Principle 5- Review and Report (ISO 14004, 1996; ISO 14001,1996).

Germiston council should also design an environmental management system for identifying the existing and predicted environmental impacts of pollution on Victoria Lake. ISO 14001 and 14004 (South African code of practice: Environmental management systems- Specifications with guidance for use) should be consulted by Germiston Council for more detailed information on designing an environmental management system for Victoria Lake and the surrounding inlets.

• Environmental Management Programme The development and implementation of environmental management plans or programmes (EMP's) is not only an integral part of the requirements of the EMS (Environmental management system), it is also the management tool for achieving the aims and objectives of an organization's environmental policy (see figure 42). The EMP would be the result or be generated from the recommendations or findings from an audit, life-cycle analysis or environmental risk assessment done for Victoria Lake and the surrounding inlets. This identification of the environmental risk and the subsequent implementation of an EMP to address the issues should be a part of the council's overall Environmental Management System for Victoria Lake. In general terms the environmental management programme is there to set out actions to be taken and standards to be met in order to avoid, control, reduce or remediate adverse environmental impacts so as to conform to environmental impact assessment findings and recommendations, environmental risks assessment findings, life cycle assessment evaluations, legislation obligations, permit requirements, license conditions and an organizations policies and standards. The focus is on achieving a desired end state.

89 Commitment to EMP Management review - Support for EMP Planning & development of -top management to EMP review EMP for -ID root causes and impacts improvement EMP to cover legal std's Set objectives, targets

Implementation of EMP Checking EMP and EMP -structures and responsibility corrective action -training awareness and -monitoring and competence measurement -communication (reporting) -corrective and preventive -operation document control action -emergency preparedness -records -audits

Figure 42. Using the EMS as the framework for the EMP (Lucas, 1997).

The EMP is a combination of a programme / scope of work / specifications to manage (through mitigation avoidance) environmental impacts associated with a particular operation /process.Its aim is to ensure that the following are in place (Lucas, 1997): responsibilities key performance indicators implementable and measurable specifications an end state or clearly defined outcome from the EMP channels of reporting a monitoring schedule and penalties for non-conformance. The environmental management programme should be developed and implemented following these steps (Lucas, 1997): Identify the environmental aspects or issues to be addressed and managed (undertake some form of assessment). Translate the above issues into specific management objectives and goals.

90 Define what is required to achieve the management objectives or goals i.e. in terms of facilities, procedures, etc. Link the above requirements to the management processes, structures, contracts, and systems. Make sure there are mechanisms to deal with the unexpected environmental problems that may arise. Have a programme of monitoring and auditing not only in terms of the environmental programmes but also on environmental variables. The EMP should be worded in such a manner as to be measurable requirements to ensure the effective implementation, control and monitoring. Responsibilities and criteria for performance measurement should also be included. The EMP should indicate timing for implementation and the period of implementation (Lucas, 1997).

7.1 Urban impoundment management

Different environmental management methods can be use to manage Victoria Lake in a sustainable way. It is however difficult to implement these methods directly on urban impoundment problems. Wiechers et al., 1996, suggest the following guiding principles for managing typical urban impoundment problems. There are three main areas in which water quality related issues could be addressed: catchment management re-impoundment treatment in-lake treatment

❑ Catchment management: Problems which manifest themselves in urban impoundments are ideally tackled at this first level through the approach of integrated catchment management (see figure 43). This philosophy is current practice internationally, and is presently being implemented in South Africa by the Department of Water Affairs and Forestry. In essence the focus of catchment management is on addressing point and non-point sources of pollution. Using this integrated approach to catchment management, Germiston Council could easily

91 design an environmental management system including an environmental management programme. Catchment management of Victoria Lake would especially focus on inlet management.

Start Water quality guidelines + Continue -0,. Collect water quality monitoring data and information V 4, Site specific water + Determine fitness for use Water fit for quality guidelines 41--- & water aualitv problems use

Water quality problems (Current or future) V Establish water quality Establish management entities objectives (Impoundment, catchment area)

V Devise overall management strategy

V Implement best management practices

Verify water quality objectives are met

/Yes

Review Continue strateev monitoring

Figure 43. Integrated approach to catchment management (Wiechers, et aL, 1996).

92 ❑ Pre-impoundment management The principle of pre-impoundment management is that poor quality water is treated in some way before being allowed into an impoundment. Germiston Council can try to enforce the treatment of effluent discharge by industries before it enters the major inlets surrounding Victoria Lake and eventually entering the Lake. A way of enforcing the treatment of effluent discharge by industries would be to require environmental management systems (EMS's) of the industries. ❑ In-lake control In-lake control strategies must be viewed as the treatment of the symptoms in most instances, rather than the causes of urban impoundment problems, which are best addressed at catchment level. A diagram depicting the philosophy behind the in-lake management of urban impoundments is shown in figure 44 (Wiechers et al., 1996).

COLLECT INFORMATION ON IMPOUNDMENT CHARACTERISTICS -area IDENTIFY PROBLEM -land use -algae -water use -sediment -water quality data -bacteria -catchment information -aesthetics

Identify and Identify and Identify and evaluate evaluate pre- evaluate in- catchment impoundment impoundment management management options options options 1L IMPLEMENT INTEGRATED MANAGEMENT OPTIONS LL MONITOR OPTIONS AND REVISE IF NECESSARY

Figure 44. The management of urban impoundments.

93 An integrated management approach which considers all of the above options should lead to sound environmental management of Victoria Lake. Germiston Council should try and gather more information on each of the management options in order to manage Victoria Lake more efficiently, since the scope of this study was not great enough to focus on each option in detail.

9. REFERENCES.

Allen, H.E., 1971: Design of sampling programs. Instrumental analysis for pollution control. Ann Arbor Science Publishers, Michigan.

Barton, B.A., 1977: Short-term effects of highway construction on the limnology of a small stream in southern Ontario. Freshwater Biol. 7, 99-108

Batley, G.E., 1989: Trace element speciation: Analytical methods and problems. CRC Press, Florida.

Bosman, H., 1996: Coparate environmental management -systems and strategies. Bulletin of the Southern African institute of ecologists and environmental scientists, 15(3), 23.

Bourg, A. C. M., 1988: Metals in aquatic and terrestrial systems: sorption, speciation and mobilization. In: Chemistry and biology of solid waste. (Eds. W. Solomons and U. Forstner). Springer-Verlag, Berlin.

Canadian water quality guidelines., 1992: Canadian water quality guidelines. Vol.1 . Environmental quality guidelines division. Ottawa, Ontario.

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10. APPENDIX.

Appendix 1. Industries contributing to the pollution of storm water drainage into Victoria Lake at the sampling localities utilized in the present study (Data courtesy of Mr. R. van Loggenberg, Germiston Council; Dallas & Day, 1993). Site Industries Possible pollutants 1,2&3 AC & DC Amature windings Arsenic Active Engineers Cadmium Addicom Copper AFD Transport Iron Alwyn Skrynwerkery Lead Amcast Manganese Astute Glass & Aluminium Mercury Auto Bumper Plastics Nickel Auto Technical Oil, fuel, diesel & grease Balkan Engineering Selenium Ballistic Amour technology Sewage Beardsey Printers Silver Bedford Repairs Zinc Brenda's Auto Services C.F. Auto Electrical PTY LTD Central Panelbeaters Chadel Engineering Continental Saunas Crankshaft Rebuilding Centre Danube Engineering Deebar Dos Engineering Doubles Die Makers East African Timbers East Rand Transmissions Electrical Board Manuf. PTY LTD Express Electroplating F&M Cast & Iron pipes and fitting Falcade Engineering Ferro Magnetic cores Fhurst Engineering Finwood Papers Freeway Handrailing PTY LTD GEC Alstohm (Elmac) General Ceramic Pottery Glaco Industries Glass Suplly GPG Engineering Hercules Brake & Clutch Hi Cap Engineering

100 Hi-Tech plastics Hotline equipment Hyundai Junction Illman Plastics Inbekica Engineering International Scales Interohm . Italian Capenter J. van Gaalen & Sons K.C. Agencies C.C. Knights Electro Galvanizers Kreuzer Engineering Kwik-Fit Linden Armature Lindsay Saker service Lorenco Trading Lumberjack M&P Engineering M.K.R. Engineering Magna Mining equipment Marble Pentelic PTY LTD Miretta Forklifts MMI-Germiston Motors & Panalbeaters Motor Body construction Italian Panelbeaters Multi Metals Norman Ross Boards Omega Gears P.G. Auto Glass P.G. Masterfit P.Z. M. Zinc Products Manufacturers Pan African Shopfitters Paper & Metal Industry PTY LTD Paper Link PG Byson Garage PG Glazing supplies PG Sealant and Mastic Co. PG Wood Germiston Pilkon Shatterprufe Polyblast Powder Coat Purchase Metals Qualitec Engineering Quinn Electrical Quletron PTY Rand Refinery Ron's Upholsterers, Panelbeaters S&G Engineering SA Paper Rolls Sakkies Windows Sappi Recycle Select Electroplating CC Signhouse Spiral Bevel Co-op Spring Manufacturing of SA PTY LTD SSM Electrical Stanhope Auto spares

1 01 Stani Properties Star Gear Cutting Super Cut Tas Engineering Team Plating Teflon Plastics Top Cut Packaging Transfrig SA PTY LTD Transvaal Engineering Specialists Tubefurn Tufnol PTY LTD Ultra Tech United Artisans United Shopfitters Upholstry City Van's General ShopFitters Versatile Gasket CO Visser Repair centre Voltex Werkswinkel Elektrisiteit, Meganies, Loodgieters. en Ketelmakers Werkswinkel, Passers Werkswinkel, Riool Werkswinkel, Skrynwerkers Wes Engineering Zerko Engineering Zunino Engineering Abkins steel Corporation Academy Brushware Arsenic Site 3,4&5 ACE Glass Cadmium Alex roadworthy centre Copper Iron Al's Wrecks Amerlaan Holdings Lead Manganese Anderson Mayor S.A. Andre's Panel & Paint Mercury Angel Products Nickel Appliance Bureau Oil, fuel, diesel & grease Armstrong Ford Selenium Auto Power Tune-up Centre Sewage Auto Zakspeed CC Silver Auto Zenith Zinc Automotive Engine Components Aztra Auto Electrical B&M Water purification Bakkie Boutique Barry & Tuckers Motor Clinic Bearcat CC Bertacco Engineering BGS Metal Works BGS Metal Works Brighter Displays Cargo East Germiston Cargo Electrical Panelbeaters Casting Manufacturers Clutch, Brakes, Services &Repairs Cobra Performance and Auto Repairs

102 Cowley Exhaust Crane Auto Electrition CV Joints Delta Tool & Die Making Mould Diode TV Sales & Services Easybeat Panelbeaters & Spraypainters Eddies Clutch and Brake Elana Engineering ELI Engineering Era Tailor & Dress Design Eternity Manufacturing Jewellers Exhaust Centre Fastline Printers Ferraris Tune- up Centre Fit-n-go Forsdicks Germiston (WS) G&T Pattern Supplies G.M. Panelbeaters Gary's Auto Electrition Germiston Brake and Clutch Gio Auto Electrical Glendal Engineering GNR Services Heleon Motors Henlec Auto Body Repairs Highland Polymers Industrial Petroleum Valves Italian Heel & Shoes Repair J.R. Auto Repairs Jabulani Motor Valet Jay's Motors Jethro Investments CC Knights Panelbeating & Spraypainting Kurt's Diesel Lawnmowers International Longtile Mac Paner & Spray Mac's Number Plates and Signs Mechanical Spares & Engineering Minit Print Motorario Air Conditioning & Sun Roofing Motorsery Mr Exhaust Mr Tyre Mr. Gearlock Natyre Norman F. Hall PTY Old Dutch Tyres PA Fitment Centre PG Auto Glass Pieters Kitchens Pipe reducer Power Treads President C.V. Centre Print Associated Pro Auto Upholstry Prontaprint

103 Propshaft centre Protea Turf Equipment Raadsdrukkery Robogate Rori Motors S.A. Canopy Centre PTY SA Exhaust Shamrock Machine Tools SP Motors & General Engineering Speedy Exhaust Services Stanler Products Steel Radial tyre Centre Stellamard Mining & Gear Cutting Supa Quick Titan Engineering Tomco Electrical Tomco Electrical Pty United Auto Care Unity Alma Shopfitters Unity Dry Cleaners Van's Work Shop Venter Autopit CC Supa Quick VIP Sales & Services Vomak Industries Vosco Auto Electrition Wella Electroplating Wetcatt group Zagato Auto Sound

Appendix 2. Water quality criteria for physical and chemical factors taken from Kempster et.d.,(1982); Kiihn (1991) and Canada (1987).

Variable

❑pH 6.0-9.0 6.5-9.0 6.5-9.0

Temperature (°C) A B

Dissolved 02 mg/I >4->5.8 >5 >5

02 saturation (%)

Conductivity A mS/m

Sodium mg/I 500 100

Magnesium mg/I 1500

104 Calcium mg/1 1000

Fluoride mg/1 1.5-1.5 1.5 1.5

Chloride mg/1 50-400 100

NO3 - NO2-N mg/I C6 F0.06

SO4 mg/1 1400 250

PO4 - P mg/1 0.1

Ca CO3 mg/1 >20->20 >20

Silica mg/1 50

K mg/1 50 50

NH4-N mg/1 0.016-124 0.016 D0.01+ D/G 1.37-2.2

TDS mg/I 800

Chromium pg/1 10-100 50 2

Copper pg/1 5-200 5 50 H2-4

Iron pg/1 200-1000 200 300 300

Manganese pg/1 100-1000 50

Nickel pg/1 25-50 50 50 H25-150

Lead pg/1 20-100 30 2 H1-7

Strontium pg/1 2000 00 E100 00

Zinc pg/1 30-100 100 50 30 a- Log [H-1, A- Depend on local conditions and life species present, B- Within 5°C of background temperature (99.9% of the time), C- Nitrate, D- Depend on pH, [Ca 21 and Dissolved Oxygen, E- 90Sr, F- Nitrite, G- Ammonia, H- Dependent on hardness.

105 Appendix 3. Results of chemical analysis obtained from RAU, Department of Chemistry (water samples taken from 07/97 to 01/98).

Table 1:Concentration Aluminum (mg/I) measured within the inlets of Victoria Lake (RAU, Department of Chemistry, 07/97-01/98). Date Samples filtered Samples Unfiltered Site 1 Site 2 Site 3 Site,4 Site 5 Site 6 Site 1 Site 2 Site 3 Site 4 Site 5 Site 6 07/97 0.6 0.3 0.4 0.5 0.3 0.3 0.6 0.3 0.4 0.9 0.2 0.3 08/97 0.6 0.3 0.3 0.3 0.5 0.3 0.6 0.3 0.4 0.3 0.7 0.3 09/97 0.6 0.3 0.3 0.4 0.3 0.3 0.7 0.3 0.3 0.6 0.4 0.3 10/97 0.8 0.5 0.5 0.3 0.4 0.4 1.0 0.5 0.6 0.4 0.5 0.4 11/97 0.7 0.3 0.4 0.3 0.5 0.4 1.2 0.3 0.4 0.4 2.9 0.4 12/97 0.5 0.2 0.4 0.3 0.4 0.4 0.8 0.2 0.4 0.4 0.9 0.4 01/98 0.6 0.2 0.5 1.0 0.5 0.3 0.6 0.1 0.4 1.0 0.5 0.3 * Under detection limit

Table 2:Concentration Calcium (mg/I) measured within the inlets of Victoria Lake (RAU, Department of Chemistry, 07/97-01/98). Samples Unfiltered Site 1 Site 2 Site 3 Site 4 Site 5 Site 6 94 56 79 53.5 31 49.5 89.7 60.8 71.6 46.6 48.5 60.6 91.5 62.5 63.9 51.0 45.3 52.5 76.0 57.5 58.4 33.9 40.9 55.8 62.3 41.8 55.3 38.9 52.7 53.1 52.7 29.0 57.4 36.7 42.8 46.7 61.0 16.9 71.1 34.2 57.2 45.3

Table 3:Concentration Copper (mg/I) measured within the inlets of Victoria Lake (RAU, Department of Chemistry, 07/97-01/98). Date Samples filtered Samples Unfiltered

Site 1 Site 2 Site 3 Site 4 Site 5 Site 6 Site 1 Site 2 Site. 3 Site 4 Site 5 Site 6 07/97 *<0.1 *<0.1 *<0.1 0.9 *<0.1 *<0.1 *<0.1 *<0.1 *<0.1 1.6 *<0.1 *<0.1 08/97 *<0.1 *<0.1 *<0.1 0.3 1.9 0.1 *<0.1 *<0.1 *<0.1 0.3 2.3 *<0.1 09/97 *<0.1 *<0.1 *<0.1 1.7 0.6 *<0.1 *<0.1 *<0.1 *<0.1 2.1 0.7 *<0.1 10/97 0.03 0.01 0.1 0.4 0.2 0.01 0.01 0.003 0.2 0.5 0.2 0.004 11/97 0.01 0.007 0.009 0.4 0.02 0.01 0.06 0.004 0.06 1.0 0.06 0.003 12/97 0.003 0.003 0.005 0.5 0.02 0.009 0.05 0.007 0.004 0.8 0.02 0.009 01/98 0.005 *<0.1 0.05 0.6 0.02 0.006 0.003 *<0.1 *<0.1 0.8 0.003 0.009

106 * Under detection limit

Table 4:Concentration Cadmium (mg/I) measured within the inlets of Victoria Lake (RAU, Department of Chemistry, 07/97-01/98). Date Samples filtered Samples Unfiltered Site 1 Site 2 Site 3 Site 4 Site 5 Site 6 Site 1 Site 2 Site 3 Site 4 Site 5 Site 6 07/97 0.0 0.0 *<0.1 *<0.1 0.0 0.0 0.0 0.0 *<0.1 *<0.1 *<0.1 0.0 08/97 0.0 0.0 0.0 0.0 *<0.1 0.0 0.0 0.0 0.0 0.0 *<0.1 0.0 09/97 0.0 0.0 0.0 *<0.1 0.0 0.0 0.0 0.0 0.0 *<0.1 0.0 0.0 10/97 *<0.1 *<0.1 *<0.1 *<0.1 *<0.1 *<0.1 *<0.1 *<0.1 0.03 *<0.1 *<0.1 *<0.1 11/97 *<0.1 *<0.1 *<0.1 *<0.1 *<0.1 *<0.1 0.03 *<0.1 0.03 0.007 *<0.1 *<0.1 12/97 *<0.1 *<0.1 *<0.1 *41.1 *<0.1 *<0.1 0.03 *<0.1 *<0.1 *<0.1 *<0.1 *<0.1 01/98 *<0.1 *<0.1 0.02 0.008 *<0.1 *<0.1 *<0.1 *<0.1 *<0.1 0.04 *<0.1 *<0.1 * Under detection limit

Table 5:Concentration Cobalt (mg/I) measured within the inlets of Victoria Lake (RAU, Department of Chemistry, 07/97-01/98). Date Samples filtered Samples Unfiltered Site 1 Site 2 Site 3 Site 4 Site 5 Site 6 Site 1 Site 2 Site 3 Site 4 Site 5 Site 6 07/97 0.1 *<0.1 *<0.1 0.3 *<0.1 *<0.1 0.1 *<0.1 *<0.1 0.3 *<0.1 *<0.1 08/97 0.1 *<0.1 *<0.1 *<0.1 0.3 *<0.1 0.1 *<0.1 *<0.1 *<0.1 0.2 *<0.1 09/97 *<0.1 0.0 0.0 0.3 *<0.1 0.0 *<0.1 0.0 0.0 0.3 0.1 0.0 10/97 0.02 *<0.1 *<0.1 0.07 0.02 *<0.1 0.03 *<0.1 0.03 0.08 0.03 *<0.1 11/97 0.02 0.002 *<0.1 0.1 0.4 0.004 0.06 *<0.1 0.05 0.1 0.4 *<0.1 12/97 0.02 *<0.1 *<0.I 0.1 0.1 *<0.1 0.07 *<0.1 *<0.1 0.1 0.1 *<0.1 01/98 0.05 *<0.1 0.03 0.04 0.03 *<0.1 0.06 *<0.1 *<0.1 0.09 0.02 *<0.1 * Under detection limit

Table 6:Concentration Chromium (mg/I) measured within the inlets of Victoria Lake (RAU, Department of Chemistry, 07/97-01/98). Date Samples filtered Samples Unfiltered Site 1 Site 2 Site 3 Site 4 Site 5 Site 6 Site 1 Site 2 Site 3 Site 4 Site 5 Site 6 07/97 0.0 0.0 0.0 *<0.1 0.0 0.0 0.0 0.0 *<0.1 *<0.1 *<0.1 0.0 08/97 0.0 0.0 0.0 0.0 *<0.1 0.0 0.0 0.0 0.0 0.0 *<0.1 0.0 09/97 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 *<0.1 0.0 0.0 10/97 *<0.1 *<0.1 0.001 *<0.1 0.004 *<0.1 *<0.1 *<0.1 0.03 *<0.1 0.008 *<0.1 11/97 *<0.1 *<0.1 *<0.1 *<0.1 *<0.1 *<0.1 0.03 0.001 0.03 *<0.1 0.03 *<0.1 12/97 *<0.1 *<0.1 *<0.1 *<0.1 *<0.1 *<0.1 0.03 *<0.1 *<0.1 0.002 *<0.1 *<0.1 01/98 *<0.1 *<0.1 0.02 *<0.1 0.002 *<0.1 *<0.1 *<0.1 *<0.1 0.02 *<0.1 *<0.1

107 * Under detection limit

Table 7:Concentration Iron (mg/1) measured within the inlets of Victoria Lake (RAU, Department of Chemistry, 07/97-01/98). Date Samples filtered Samples Unfiltered Site 1 Site 2 Site 3 Site 4 Site 5 Site 6 Site 1 Site 2 Site 3 Site 4 Site 5 Site 6 07/97 1.3 0.3 *<0.1 0.1 0.2 *<0.1 2.3 0.4 0.1 0.1 0.3 *<0.1 08/97 2.9 0.6 *<0.1 0.2 0.1 0.1 2.9 0.5 0.2 0.3 0.2 0.2 09/97 2.4 0.4 *<0.1 *<0.1 0.3 *<0.1 3.3 0.4 0.1 0.1 0.4 0.1 10/97 2.7 1.0 0.3 0.4 1.1 0.09 3.9 0.7 0.4 0.5 1.3 0.09 11/97 3.2 0.5 0.07 0.4 13.2 0.07 4.4 0.5 0.1 0.4 20.8 0.1 12/97 2.0 0.1 0.02 0.07 1.6 0.05 3.9 0.2 0.03 0.1 4.0 0.06 01/98 3.1 0.4 0.07 0.3 0.7 0.07 3.8 0.3 0.05 0.2 0.9 0.09 * Under detection limit

Table 8:Concentration Lead (mg/1) measured within the inlets of Victoria Lake (RAU, Department of Chemistry, 07/97-01/98). Date Samples filtered Samples Unfiltered Site 1 Site 2 Site 3 Site 4 Site 5 Site 6 Site 1 Site 2 Site 3 Site 4 Site 5 Site 6 07/97 *<0.1 *<0.1 *<0.1 *<0.1 *<0.1. *<0.1 *<0.1 *<0.1 *<0.1 *<0.1 *<0.1 *<0.1 08/97 *<0.1 *<0.1 *<0.1 *<0.1 *<0.1 *<0.1 *<0.1 *<0.1 *<0.1 *<0.1 0.1 *<0.1 09/97 *<0.1 *<0.1 *<0.1 *<0.1 *<0.1 0.0 *<0.1 *<0.1 *41.1 *<0.1 *<0.1 *<0.1 10/97 0.02 0.007 0.02 0.05 0.009 0.04 0.04 0.02 0.006 0.07 1.3 *<0.1 11/97 0.04 0.04 0.04 0.08 0.05 0.04 0.05 *<0.1 0.04 0.08 0.1 *<0.1 12/97 0.02 0.01 0.007 0.09 0.01 0.02 0.06 0.03 0.02 0.09 0.03 0.04 01/98 0.008 *<0.1 0.03 0.2 0.01 *<0.1 0.04 *<0.1 0.009 0.3 *<0.1 0.01 * Under detection limit

Table 9:Concentration Manganese (mg/I) measured within the inlets of Victoria Lake (RAU, Department of Chemistry, 07/97-01/98). Date Samples filtered Samples Unfiltered Site 1 Site 2 Site 3 Site 4 Site 5 Site 6 Site 1 Site 2 Site 3 Site 4 Site 5 Site 6 07/97 5.9 0.2 *<0.1 18.0 0.5 *<0.1 4.6 0.3 *<0.1 17.3 0.1 *<0.1 08/97 5.2 0.7 *<0.1 3.0 15.5 0.3 4.4 0.5 *<0.1 2.8 14.8 *<0.1 09/97 8.0 0.9 *<0.1 22.7 7.1 0.2 7.1 0.7 *<0.1 19.8 6.0 *<0.1 10/97 3.6 0.7 0.03 5.2 1.9 0.1 3.7 0.5 0.06 5.3 1.9 0.07 11/97 3.2 0.4 0.04 7.2 0.8 0.3 3.1 0.4 0.06 8.0 0.8 0.06 12/97 3.2 0.5 0.04 6.6 0.5 0.07 3.2 0.5 0.02 6.4 0.4 0.06 01/98 3.3 0.2 0.08 3.0 0.3 0.05 3.5 0.1 0.02 3.2 0.3 0.05

108 * Under detection limit

Table 10:Concentration Nickel (mg/1) measured within the inlets of Victoria Lake (RAU, Department of Chemistry, 07/97-01/98). Date Samples filtered Samples Unfiltered Site 1 Site 2 Site 3 Site 4 Site 5 Site 6 Site 1 Site 2 Site 3 Site 4 Site 5 Site 6 07/97 0.3 *<0.1 *<0.1 0.2 0.1 *<0.1 0.2 *<0.1 *<0.1 0.2 *<0.1 *<0.1 08/97 0.2 *<0.1 *<0.1 *<0.1 0.2 *<0.1 0.2 *<0.1 *<0.1 *<0.1 0.2 *<0.1 09/97 *<0.1 *<0.1 0.0 0.2 *<0.1 *<0.1 *<0.1 *<0.1 0.0 0.2 0.1 *<0.1 10/97 0.07 0.02 0.005 0.07 0.04 0.02 0.08 0.01 0.04 0.07 0.05 0.01 11/97 0.06 0.01 0.006 0.1 1.0 0.03 0.1 *<0.1 0.05 0.1 1.1 0.02 12/97 0.05 *<0.1 0.002 0.09 0.3 0.1 0.09 0.009 *<0.1 0.09 0.3 0.02 01/98 0.09 *<0.1 0.04 0.06 0.2 0.02 0.1 *<0.1 *<0.1 0.1 0.2 0.02 * Under detection limit

Table 11:Concentration Zinc(mg/l) measured within the inlets of Victoria Lake (RAU, Department of Chemistry, 07/97-01/98). Date Samples filtered Samples Unfiltered Site 1 Site 2 Site 3 Site 4 Site 5 Site 6 Site 1 Site 2 Site 3 Site 4 Site 5 Site 6 07/97 0.1 0.1 0.1 9.3 0.2 *<0.1 0.1 0.1 0.1 9.1 *<0.1 *<0.1 08/97 0.1 0.1 *<0.1 1.7 9.5 0.2 0.1 0.1 *<0.1 1.6 9.4 *<0.1 09/97 0.1 *<0.1 *<0.1 11.4 3.5 0.2 *<0.1 *<0.1 0.1 11.3 3.3 *<0.1 10/97 0.2 0.2 1.4 3.0 1.1 0.08 0.1 0.1 1.6 3.4 1.3 0.01 11/97 0.1 0.1 0.2 2.4 1.1 0.1 0.2 0.1 0.2 4.6 1.2 0.03 12/97 0.06 0.2 0.3 4.2 0.4 0.04 0.1 0.2 0.3 4.2 0.3 0.03 01/98 0.1 0.3 0.3 2.8 0.3 0.04 0.2 0.2 0.2 3.0 0.2 0.03 * Under detection limit

Appendix 4. Results of chemical water analysis obtained from Rand Water (water samples taken from 07/97-06/98).

Table 1:Concentration Alkalinity, CaCO3 (mg/1), measured within the inlets of Victoria Lake (Rand Water, 07/97-06/98). Date Samples Unfiltered Site 1 Site 2 Site 3 Site 4 Site 5 Site 6 07/97 *<5.0 N/S N/S *<5.0 *<5.0 *<5.0 08/97 *<5.0 *<5.0 *<5.0 *<5.0 *<5.0 *<5.0 09/97 *<5.0 68 136 20 *<5.0 N/S 10/97 60 71 130 100 100 63 11/97 54 58 130 73 *<5.0 70

109 12/97 54 50 110 43 39 54 01/98 *<5.0 38 48 *<5.0 *<5.0 *<5.0 02/98 N/S N/S N/S N/S N/S N/S 03/98 93 70 120 63 83 45 04/98 95 92 116 52 97 47 05/98 78 98 130 127 87 66 06/98 64 79 92 46 81 52 *Under detection limit N/S Insufficient Sample

Table 2:Concentration Aluminum (mg/I) measured within the inlets of Victoria Lake, samples filtered (Rand Water, 02/98-06/98). Date Samples filtered Site 1 Site 2 Site 3 Site 4 Site 5 Site 6 02/98 N/S N/S N/S N/S N/S N/S 03/98 0.13 *<0.1 0.11 *<0.1 *<0.1 0.47 04/98 0.51 0.4 N/s 0.39 0.38 0.46 05/98 0.48 0.36 0.41 0.41 0.77 N/S 06/98 *<0.1 *<0.1 *<0.1 *<0.1 *<0.1 *<0.1 * Under detection rmit N/S Insufficient Sample

Table 3:Concentration Aluminum (mg/I) measured within the inlets of Victoria Lake, samples unfiltered (Rand Water, 02/98-06/98). Date Samples Unfiltered Site 1 Site 2 Site 3 Site 4 Site 5 Site 6 02/98 N/S N/S N/S N/S N/S N/S 03/98 *<0.1 *<0.1 *<0.1 0.11 0.16 *<0.1 04/98 0.63 0.39 0.58 1.3 N/S 0.51 05/98 0.51 0.44 0.36 N/S N/S N/S 06/98 *<0.1 *<0.1 *<0.1 0.4 *<0.1 *<0.1 * Under detection limit N/S Insufficient Sample

110 Table 4:Concentration Ammonia, N (mg/1), measured within the inlets of Victoria Lake (Rand Water, 07/97-06/98). Date Samples Unfiltered Site 1 Site 2 Site 3 Site 4 Site 5 Site 6 07/97 0.76 0.1 N/S 2.5 0.59 3.0 08/97 2.0 0.25 0.29 0.63 1.8 0.18 09/97 0.76 *<0.05 0.16 5.1 1.8 N/S 10/97 N/S N/S N/S N/S N/S N/S 11/97 N/S N/S N/S N/S N/S N/S 12/97 N/S N/S N/S N/S N/S N/S 01/98 0.23 0.03 *<0.05 0.31 0.18 *<0.05 02/98 N/S N/S N/S N/S N/S N/S 03/98 *<0.05 *<0.05 *<0.05 1.2 0.24 *<0.05 04/98 0.1 0.06 0.01 0.01 0.5 0.03 05/98 0.1 0.1 0.02 0.1 0.1 0.03 06/98 *<0.05 *<0.05 0.19 0.52 *<0.05 0.06 *Under detection limit N/S Insufficient Sample

Table 5:Concentration Cadmium (mg/1) measured within the inlets of Victoria Lake, samples filtered (Rand Water, 02/98-06/98). Date Samples filtered Site 1 Site 2 Site 3 Site 4 Site 5 Site 6 02/98 N/S N/S N/S N/S N/S N/S 03/98 *<0.05 *<0.05 *<0.05 *<0.05 *<0.05 *<0.05 04/98 0.001 0.003 N/S 0.012 0.001 0.0003 05/98 0.0003 0.0003 0.0003 0.0003 0.0003 N/S 06/98 *<0.05 *<0.05 *<0.05 *<0.05 *<0.05 *<0.05 * Under detection l'mit N/S Insufficient Sample

Table 6:Concentration Cadmium (mg/I) measured within the inlets of Victoria Lake, samples unfiltered (Rand Water, 02/98-06/98). Date Samples Unfiltered Site 1 Site 2 Site 3 Site 4 Site 5 Site 6 02/98 N/S N/S N/S N/S N/S N/S 03/98 *<0.05 *<0.05 *<0.05 *<0.05 *<0.05 *<0.05 04/98 0.0003 0.0003 0.001 0.0003 N/S 0.0003

111 05/98 0.008 0.0003 0.0003 N/S N/S N/S 06/98 *<0.05 *<0.05 *<0.05 *<0.05 *<0.05 *<0.05 * Under detection limit N/S Insufficient Sample

Table 7:Concentration Calcium (mg/1) measured within the inlets of Victoria Lake, samples unfiltered (Rand Water, 02/98-06/98). Date Samples Unfiltered Site 1 Site 2 Site 3 Site 4 Site 5 Site 6 02/98 N/S N/S N/S N/S N/S N/S 03/98 70 78 47 34 41 44 04/98 51 44 45 40 33 45 05/98 51 51 44 32 30 48 06/98 56 56 43 43 25 53 * Under detection 1 -mit

Table 8:Concentration Chemical Oxygen Demand (mg/I), measured within the inlets of Victoria Lake (Rand Water, 07/97-06/98). Date Samples Unfiltered Site 1 Site 2 Site 3 Site 4 Site 5 Site 6 07/97 N/S 5.9 N/S N/S 20 19 08/97 N/S 13 24 30 14 N/S 09/97 36 27 21 24 39 N/S 10/97 52 45 47 33 48 42 11/97 63 39 22 52 50 29 12/97 47 23 23 32 22 29 01/98 N/S 31 N/S 29 N/S 17 02/98 N/S N/S N/S N/S N/S N/S 03/98 N/S N/S N/S N/S N/S N/S 04/98 6.8 7.1 7.8 7.6 7.5 7.5 05/98 7.3 7.3 7.5 7.8 7.2 7.7 06/98 N/S N/S N/S N/S N/S N/S *Under detection limit N/S Insufficient Sample

112 Table 9:Concentration Chloride, Cl (mg/I), measured within the inlets of Victoria Lake (Rand Water, 07/97-06/98). Date Samples Unfiltered Site 1 Site 2 Site 3 Site 4 Site 5 Site 6 07/97 125 N/S N/S 145 N/S 14 08/97 23 N/S N/S N/S N/S 145 09/97 160 35 N/S N/S 71 N/S 10/97 N/S N/S N/S N/S N/S N/S 11/97 N/S N/S N/S N/S N/S N/S 12/97 N/S N/S N/S N/S N/S N/S 01/98 76 N/S 31 N/S 22 N/S 02/98 N/S N/S N/S N/S N/S N/S 03/98 110 17 21 80 28 25 04/98 69 35 38 156 47 49 05/98 48 36 36 130 35 38 06/98 30 36 17 130 16 21 *Under detection limit N/S Insufficient Sample

Table 10:Concentration Chromium (mg/I) measured within the inlets of Victoria Lake, samples filtered (Rand Water, 02/98-06/98). Date Samples Filtered Site 1 Site 2 Site 3 Site 4 Site 5 Site 6 02/98 N/S N/S N/S N/S N/S N/S 03/98 *<0.05 *<0.05 *<0.05 *<0.05 *<0.05 *<0.05 04/98 0.023 0.028 N/S 0.032 0.028 0.026 05/98 0.03 0.03 0.023 0.021 0.019 N/S 06/98 *<0.05 *<0.05 *<0.05 *<0.05 *<0.05 *<0.05 * Under detection Emit N/S Insufficient Sample

Table 11:Concentration Chromium (mg/I) measured within the inlets of Victoria Lake, samples unfiltered (Rand Water, 02/98-06/98). Date Samples Unfiltered Site 1 Site 2 Site 3 Site 4 Site 5 Site 6 02/98 N/S N/S N/S N/S N/S N/S 03/98 *<0.05 *<0.05 *<0.05 *<0.05 *<0.05 *<0.05 04/98 0.045 0.028 0.017 0.04 N/S 0.036

113 05/98 0.034 0.01 0.034 N/S N/S N/S 06/98 *<0.05 *<0.05 *<0.05 *<0.05 *<0.05 *<0.05 * Under detection limit N/S Insufficient Sample

Table 12:Concentration Cobalt (mg/I) measured within the inlets of Victoria Lake, samples filtered (Rand Water, 02/98-06/98). Date Samples filtered Site 1 Site 2 Site 3 Site 4 Site 5 Site 6 02/98 N/S N/S N/S N/S N/S N/S 03/98 *<0.1 *<0.1 *<0.1 *<0.1 *<0.1 *<0.1 04/98 0.005 0.0009 N/S 0.263 0.027 0.0009 05/98 0.0 0.001 0.0009 0.001 0.006 N/S 06/98 *<0.1 *<0.1 *<0.1 0.26 *<0.1 *<0.1 * Under detection limit N/S Insufficient Sample

Table 13:Concentration Cobalt (mg/I) measured within the inlets of Victoria Lake, samples unfiltered (Rand Water, 02/98-06/98). Date Samples Unfiltered Site 1 Site 2 Site 3 Site 4 Site 5 Site 6 02/98 N/S N/S N/S N/S N/S N/S 03/98 *<0.1 *<0.1 *<0.1 0.13 *<0.1 • *<0.1 04/98 0.011 0.001 0.02 0.264 N/S 0.001 05/98 0.161 0.002 0.0009 N/S N/S N/S 06/98 *<0.1 *<0.1 *<0.1 0.27 *<0.1 *<0.1 * Under detection rmit N/S Insufficient Sample

Table 14:Concentration Copper (mg/I) measured within the inlets of Victoria Lake, samples filtered (Rand Water, 02/98-06/98). Date Samples filtered Site 1 Site 2 Site 3 Site 4 Site 5 Site 6 02/98 N/S N/S N/S N/S N/S N/S 03/98 0.69 *<0.1 *<0.1 0.63 *<0.1 *<0.1 04/98 0.024 0.024 N/S 1.19 0.024 0.024 05/98 0.024 0.024 0.024 0.024 0.024 N/S 06/98 *<0.1 *<0.1 *<0.1 1.3 *<0.1 *<0.1 * Under detection l'mit N/S Insufficient Sample

114 Table 15:Concentration Copper (mg/I) measured within the inlets of Victoria Lake, samples unfiltered (Rand Water, 02/98-06/98). Date Samples Unfiltered Site 1 Site 2 Site 3 Site 4 Site 5 Site 6 02/98 N/S N/S N/S N/S N/S N/S 03/98 *<0.1 *<0.1 *<0.1 0.69 *<0.1 *<0.1 04/98 0.024 0.024 0.211 2.53 N/S 0.024 05/98 1.31 0.024 0.024 N/S N/S N/S 06/98 *<0.1 *<0.1 *<0.1 2.7 *<0.1 *<0.1 * Under detection limit N/S Insufficient Sample

Table 16:Concentration Iron (mg/I) measured within the inlets of Victoria Lake, samples filtered (Rand Water, 02/98-06/98). Date Samples filtered Site 1 Site 2 Site 3 Site 4 Site 5 Site 6 02/98 N/S N/S N/S N/S N/S N/S 03/98 0.97 0.56 0.31 0.22 1.6 0.15 04/98 0.192 0.088 N/S 0.016 0.258 0.062 05/98 0.059 0.125 0.091 0.056 0.973 N/S 06/98 0.6 0.19 0.05 0.11 0.38 0.05 * Under detection limit N/S Insufficient Sample

Table 17:Concentration Iron (mg/I) measured within the inlets of Victoria Lake, samples unfiltered (Rand Water, 02/98-06/98). Date Samples Unfiltered Site 1 Site 2 Site 3 Site 4 Site 5 Site 6 02/98 N/S N/S N/S N/S N/S N/S 03/98 1.6 0.44 0.18 0.16 0.44 0.18 04/98 1.87 0.134 0.58 0.095 N/S 0.586 05/98 0.264 0.463 0.027 N/S N/S N/S 06/98 1.1 0.28 0.05 0.78 0.74 0.14 * Under detection limit N/S Insufficient Sample

115 Table 18:Concentration Lead (mg/I) measured within the inlets of Victoria Lake, samples filtered (Rand Water, 02/98-06/98). Date Samples Filtered Site 1 Site 2 Site 3 Site 4 Site 5 Site 6 02/98 N/S N/S N/S N/S N/S N/S 03/98 *<0.3 *<0.3 *<0.3 *<0.3 *<0.3 *<0.3 04/98 0.004 0.004 N/S 0.061 0.008 0.004 05/98 0.004 0.004 0.004 0.085 0.008 N/S 06/98 *<0.3 *<0.3 *<0.3 *<0.3 *<0.3 *<0.3 * Under detection 1"mit N/S Insufficient Sample

Table 19:Concentration Lead (mg/I) measured within the inlets of Victoria Lake, samples unfiltered (Rand Water, 02/98-06/98). Date Samples Unfiltered Site 1 Site 2 Site 3 Site 4 Site 5 Site 6 02/98 N/S N/S N/S N/S N/S N/S 03/98 *<0.3 *<0.3 *<0.3 0.16 *<0.3 *<0.3 04/98 0.013 0.004 0.025 0.209 N/S 0.06 05/98 0.107 0.004 0.004 N/S N/S N/S 06/98 *<0.3 *<0.3 *<0.3 0.14 *<0.3 *<0.3 * Under detection limit N/S Insufficient Sample

Table 20:Concentration Manganese (mg/I) measured within the inlets of Victoria Lake, samples filtered (Rand Water, 02/98-06/98). Date Samples filtered Site 1 Site 2 Site 3 Site 4 Site 5 Site 6 02/98 N/S N/S N/S N/S N/S N/S 03/98 1.5 0.54 *<0.1 8.4 0.23 *<0.1 04/98 0.867 0.044 N/S 15.6 1.95 1.13 05/98 0.041 0.172 0.015 0.056 0.973 N/S 06/98 0.68 0.16 *<0.1 16 0.14 *<0.1 * Under detection limit N/S Insufficient Sample

116 Table 21:Concentration Manganese (mg/I) measured within the inlets of Victoria Lake, samples unfiltered (Rand Water, 02/98-06/98). Date Samples Unfiltered Site 1 Site 2 Site 3 Site 4 Site 5 Site 6 02/98 N/S N/S N/S N/S N/S N/S 03/98 1.5 0.5 *<0.1 8.3 0.21 *<0.1 04/98 1.04 0.044 N/S 15.6 1.95 1.13 05/98 9.41 0.6 0.009 N/S N/S N/S 06/98 0.76 0.17 *<0.1 16 *<0.1 *<0.1 * Under detection limit N/S Insufficient Sample

Table 22:Concentration Nickel (mg/I) measured within the inlets of Victoria Lake, samples filtered (Rand Water, 02/98-06/98). Date Samples filtered Site 1 Site 2 Site 3 Site 4 Site 5 Site 6 02/98 N/S N/S N/S N/S N/S N/S 03/98 *<0.1 *<0.1 *<0.1 *<0.1 *<0.1 *<0.1 04/98 0.02 0.06 N/S 0.171 0.028 0.005 05/98 0.007 0.004 0.001 0.007 0.019 N/S 06/98 *<0.1 *<0.1 *<0.1 0.2 *<0.1 *<0.1 * Under detection limit N/S Insufficient Sample

Table 23:Concentration Nickel (mg/I) measured within the inlets of Victoria Lake, samples unfiltered (Rand Water, 02/98-06/98). Date Samples Unfiltered Site 1 Site 2 Site 3 Site 4 Site 5 Site 6 02/98 N/S N/S N/S N/S N/S N/S 03/98 *<0.1 *<0.1 *<0.1 0.15 *<0.1 *<0.1 04/98 0.031 0.007 0.025 0.172 N/S 0.01 05/98 0.224 0.006 0.01 N/S N/S N/S 06/98 *<0.1 *<0.1 *<0.1 0.2 *<0.1 *<0.1 * Under detection N/S Insufficient Sample

117 Table 24:Concentration Nitrate, N (mg/I), measured within the inlets of Victoria Lake (Rand Water, 07/97-06/98). Date Samples Unfiltered Site 1 Site 2 Site 3 Site 4 Site 5 Site 6 07/97 *<0.1 N/S N/S *<0.1 *<0.1 *<0.1 08/97 *<0.1 *<0.1 *<0.1 0.4 0.19 *<0.1 09/97 *<0.1 0.19 3.9 22 8.8 N/S 10/97 N/S N/S N/S N/S N/S N/S 11/97 N/S N/S N/S N/S N/S N/S 12/97 N/S N/S N/S N/S N/S N/S 01/98 0.24 0.03 4.7 3.7 3.3 0.4 02/98 N/S N/S N/S N/S N/S N/S 03/98 *<0.1 *<0.1 2.9 11 3.2 *<0.1 04/98 *<0.1 *<0.1 *<0.1 *<0.1 *<0.1 *<0.1 05/98 0.3 1.5 1.8 11 1.3 0.3 06/98 0.15 0.24 2.8 15 1.1 0.15 *Under detection limit N/S Insufficient Sample

Table 25:Concentration Nitrite, N (mg/1), measured within the inlets of Victoria Lake (Rand Water, 07/97-06/98). Date Samples Unfiltered Site 1 Site 2 Site 3 Site 4 Site 5 Site 6 07/97 *<0.03 N/S *<0.03 *<0.03 *<0.03 *<0.03 08/97 *<0.03 *<0.03 *<0.03 *<0.03 *<0.03 *<0.03 09/97 *<0.03 *<0.03 0.18 0.04 0.11 N/S 10/97 N/S N/S N/S N/S N/S N/S 11/97 N/S N/S N/S N/S N/S N/S 12/97 N/S N/S N/S N/S N/S N/S 01/98 *<0.03 0.24 *<0.03 0.04 0.07 *<0.03 02/98 N/S N/S N/S N/S N/S N/S 03/98 *<0.03 *<0.03 0.04 *<0.03 0.18 *<0.03 04/98 0.4 0.4 0.4 0.4 0.4 0.4 05/98 0.4 0.4 0.4 0.4 0.4 0.4 06/98 *<0.03 *<0.03 *<0.03 *<0.03 *<0.03 *<0.03 *Under detection limit N/S Insufficient Samples

118 Table 26:Concentration Orto-phosphates, P (mg/I), measured within the inlets of Victoria Lake (Rand Water, 07/97-06/98). Date Samples Unfiltered Site 1 Site 2 Site 3 Site 4 Site 5 Site 6 07/97 0.47 0.1 N/S 0.32 0.3 0.27 08/97 2.0 *<0.03 0.37 0.44 0.19 0.13 09/97 *<0.03 0.06 3.9 22 *<0.03 N/S 10/97 N/S N/S N/S N/S N/S N/S 11/97 N/S N/S N/S N/S N/S N/S 12/97 N/S N/S N/S N/S N/S N/S 01/98 *<0.03 N/S 0.11 3.7 *<0.03 0.24 02/98 N/S N/S N/S N/S N/S N/S 03/98 0.4 *<0.03 *<0.03 *<0.03 *<0.03 *<0.03 04/98 0.1 0.1 0.1 0.1 0.1 0.1 05/98 0.1 0.1 0.1 0.1 0.1 0.1 06/98 0.08 *<0.03 0.09 *<0.03 0.11 N/S *Under detection limit N/S Insufficient sample

Table 27:Concentration Suspended Solids (mg/l) measured within the inlets of Victoria Lake (Rand Water, 07/97-06/98). Date Samples Unfiltered Site 1 Site 2 Site 3 Site 4 Site 5 Site 6 07/97 N/S 98 N/S N/S N/S N/S 08/97 N/S N/S N/S N/S N/S N/S 09/97 N/S N/S N/S N/S N/S N/S 10/97 N/S N/S N/S N/S N/S N/S 11/97 N/S N/S N/S N/S N/S N/S 12/97 N/S N/S N/S N/S N/S N/S 01/98 N/S N/S N/S N/S N/S N/S 02/98 N/S N/S N/S N/S N/S N/S 03/98 20 2.0 9.0 10 18 40 04/98 37 8 39 50 48 12

119 Table 28:Concentration Sulphate, SO 4 (mg/I), measured within the inlets of Victoria Lake (Rand Water, 07/97-06/98). Date Samples Unfiltered Site 1 Site 2 Site 3 Site 4 Site 5 Site 6 07/97 N/S 277 N/S N/S 58 N/S 08/97 N/S 76 21 40 130 N/S 09/97 N/S N/S N/S N/S N/S N/S 10/97 240 99 9.0 57 60 96 11/97 212 72 102 57 159 102 12/97 174 45 93 69 96 96 01/98 N/S 10 N/S 85 N/S N/S 02/98 N/S N/S N/S N/S N/S N/S 03/98 360 94 145 87 84 135 04/98 185 102 125 134 68 142 05/98 182 116 82 99 43 148 06/98 205 180 145 170 48 200 *Under detection limit N/S Insufficient Sample

Table 29:Concentration Zinc (mg/1) measured within the inlets of Victoria Lake, samples filtered (Rand Water, 02/98-06/98). Date Samples filtered Site 1 Site 2 Site 3 Site 4 Site 5 Site 6 02/98 N/S N/S N/S N/S N/S N/S 03/98 0.17 0.2 0.7 4.5 0.24 0.12 04/98 0.0002 0.007 N/S 8.52 0.909 0.0002 05/98 0.0002 0.0002 0.021 0.0002 0.0002 N/S 06/98 0.2 0.19 0.16 7.5 0.17 0.18 * Under detection limit N/S Insufficient Sample

Table 30:Concentration Zinc (mg/I) measured within the inlets of Victoria Lake, samples unfiltered (Rand Water, 02/98-06/98). Date Samples Unfiltered Site 1 Site 2 Site 3 Site 4 Site 5 Site 6 02/98 N/S N/S N/S N/S N/S N/S 03/98 0.4 0.2 0.56 4.5 0.22 0.1 04/98 0.0002 0.0002 0.727 9.18 N/S 0.046

120 05/98 6.31 0.0002 0.013 N/S N/S N/S 06/98 0.13 0.15 0.2 8.2 0.14 0.17 * Under detection Emit N/S Insufficient Sample

Appendix 5: Data obtained on site with various equipment by the researcher.

Table 1. Conductivity of the water of the inlets of Victoria Lake, 07/97-06/97. Date Sitel Site 2 Site 3, Site 4 Site 5 Site 6 07/97 1715 pS/cm 666µS/cm 968µS/cm 1019 µS/cm 696µS/cm 536µS/cm 08/97 1608µS/cm 830µS/cm 798µS/cm 946µS/cm 580pS 594µS/cm 09/97 1910µS/cm 715 gS/cm 791µS/cm 1243µS/cm 760µS/cm 588µS/cm 10/97 1571pS/cm 778µS/cm 897µS/cm 788p S/cm 969µS/cm 766p S/cm 11/97 1069µS/cm 441 gS/cm 632µS/cm 696 pS/cm 723 p S/cm 569 pS/cm 12/97 903µS/cm 293 pS/cm 628µS/cm 57.9µS/cm 499µS/cm 109.6µS/cm 01/98 1173 pS/cm 241µS/cm 116111S/cm 574µS/cm 657µS/cm 55 I pS/cm 02/98 1600µS/cm 620µS/cm 954µS/cm 88812S/cm 506µS/cm 534µS/cm 03/98 1076 pS/cm 456µS/cm 616µS/cm 692µS/cm 508µS/cm 546µS/cm 04/98 810µS/cm 494 pS/cm 636µS/cm 140µS/cm 520µS/cm 544 gS/cm 05/98 102.5µS/cm 79.9µS/cm 459µS/cm 760µS/cm 316µS/cm 436µS/cm 06/98 601 pS/cm 520 gS/cm 610µS/cm 810µS/cm 400µS/cm 520µS/cm

Table 2. Concentration dissolved oxygen (mg/1) measured in the water of the inlets of Victoria Lake, 07/97-06/97. Date Sitel Site 2 Site"3 Siie 4 Site 5 Site 6 07/97 14.1 9.7 7.8 8.1 3.1 10.2 08/97 13.1 5.3 10.5 11.5 3.3 11.4 09/97 1.15 1.96 7.60 6.54 4.49 9.0 10/97 1.75 0.07 6.90 5.46 7.95 7.07 11/97 0.49 1.91 6.89 5.24 7.71 5.78 12/97 0.5 3.8 12.9 15.1 9.8 9.2 01/98 5.6 12.3 7.4 9.4 8.2 10.0 02/98 1.01 5.43 7.74 4.83 8.28 7.7 03/98 7.42 3.97 6.62 7.15 1.61 6.84 04/98 7.59 2.46 9.15 7.42 1.70 8.26 05/98 7.90 3.33 7.68 8.02 3.58 9.58 06/98 7.5 5.2 7.3 9.1 3.1 6.0

121 Table 3. Percentage Oxygen Saturation measured in the water of the inlets of Victoria Lake, 07/97- 06/97. Date Site! . Site 2 Site 3„ Site 4 Site 5 Site 6 07/97 165% 101% 94% 100% 35% 120% 08/97 153% 60% 124% 129% 40% 133% 09/97 14.2% 29% 94.4% 81.06% 60.1% 128% 10/97 20.9% 1.0% 88.6% 70.2% 101.5% 92.2% 11/97 6.2% 24.6% 89.5% 69.4% 97.5% 76.3% 12/97 8% 54% 180% 190% 126% 125% 01/98 78% 175% 100% 140% 106% 140% 02/98 13.5% 72% 105.1% 66.3% 114.6% 106.4% 03/98 92.3% 55.1% 82.1% 91% 14.6% 88.5% 04/98 95% 26% 128% 92.3% 20.4% 102.1% 05/98 87.5% 35.7% 95.4% 99.7% 44.8% 112.5% 06/98 71% 71% 83% 92% 38% 75%

Table 4 . pH of the water of the inlets of Victoria Lake, 07/97-06/97. Date Sitel .1 Site 2 Site 3 Site 4 Site 5 Site 6 07/97 7.98 7.07 6.28 7.14 7.53 7.51 08/97 7.43 7.0 7.94 7.48 7.51 8.58 09/97 6.79 6.57 7.73 6.7 7.37 8.10 10/97 6.91 6.72 7.69 7.95 8.66 8.28 11/97 6.63 6.48 7.62 5.65 7.59 7.92 12/97 6.60 6.56 7.81 7.10 5.79 7.89 01/98 6.77 6.45 7.81 7.13 7.24 8.15 02/98 8.15 8.36 8.04 7.99 7.65 8.48 03/98 8.18 7.92 8.06 7.90 7.87 8.18 04/98 7.46 7.24 8.20 7.36 7.73 8.76 05/98 7.90 3.33 7.68 8.02 3.58 9.58 06/98 7.2 6.9 7.5 7.5 7.5 7.7

Table 5. Temperature (°C ) of the water of the inlets of Victoria Lake, 07/97-06/97. Date Sitel Site 2 • Site 3 Site 4 Site 5 Site 6 07/97 14.1 9 15,1 16,7 15 13.7 08/97 14.5 13.4 15.9 14.9 16.5 14.9 09/97 21.7 21.8 17.8 25.8 22.2 22.2

122 10/97 14.5 18.1 18.2 18.7 19.1 18.5 11/97 15.7 17.5 18.4 19.1 17.3 18.6 12/97 21.3 21.4 20.5 20.2 21.6 23.2 01/98 23.3 22.4 21.4 23.8 21.2 24.1 02/98 19.6 19.3 23.3 20.7 21.2 21.6 03/98 19.9 20.9 22 21.3 21.3 21.4 04/98 17.4 17.3 20.8 20.6 20.7 20.3 05/98 10.9 10.1 17.7 15.7 17.5 14.3 06/98 10.0 7.2 16 16.3 16.9 15.3

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