An Integrated Manual for the Management, Control and Protection of the Vaal River Barrage Res Ervoir

AN INTEGRATED MANUAL FOR THE MANAGEMENT, CONTROL AND PROTECTION OF THE VAAL RIVER BARRAGE RES ERVOIR.

FRANCOIS VAN WYK

MINI-DISSERTATION

Submitted in fulfillment of the requirements for the degree

MAGISTER SCIENTAE

GEOGRAPHY AND ENVIRONMENTAL MANAGEMENT

in the

Faculty of Science

at the

RAND AFRIKAANS UNIVERSITY

Supervisor: Prof. T. Harmse

November 2001 ii

OPSOMMING.

Die Vaalrivierbarragereservoir is in 1923 deur Rand Waterraad voltooi om aan die drinkwaterbehoeftes van die snelgroeiende Witwatersrand te voldoen.

Die wateraanvraag gedurende die laaste 15-20 jaar het aansienlik toegeneem, wat geweldige druk op die volhoubaarheid van die Vaalrivier as ‘n drinkwaterbron geplaas het. Die Vaalrivierbarrage dreineer ‘n hoogs ontwikkelde area met intensiewe industriële en mynbouaktiwiteite aan die orde van die dag. Industriële afloopwater wat in die opvangsgebied gegenereer word, het tot gevolg dat die watergehalte in die Barrage reservoir stelselmatig versleg het, wat die voorsiening van hoë kwaliteit drinkwater beïnvloed.

Rand Water onderhou ‘n intensiewe hulpbronbestuursisteem om besoedeling van hierdie belangrike waterbron te bekamp. Alhoewel oorwegend meer water uit die Vaaldam gebruik word vir drinkwaterdoeleindes, bly die Barrage reservoir ‘n bron in tye van droogte, en vervul dit ook ‘n addisionele funksie in die sin dat dit een van die mees gesogte areas vir waterverwante rekreasieaktiwiteite in die Witwatersrandgebied is.

Rand Water is voorts ook ‘n leier op die gebied van verantwoordelike omgewingsbestuur, en spesiale aandag word ook gewy aan die beskermnig van die akwatiese ekosisteem.

Ten einde te verseker dat die water te alle tye geskik is vir bg. Gebruike, vereis ‘n geïntegreerde reservoirbestuursprogram wat ‘n verskeidenheid aspekte insluit.

Daar bestaan geen twyfel dat wetgewing ruim voorsiening maak vir die bestuur van die Barrage reservoir nie, en dat Rand Water die aangewese liggaam is om die wette te implementeer nie.

Dit is die doel van hierdie skripsie om die verskillende aspekte rondom die bestuur van die Vaalrivierbarragereservoir te identifiseer en te beskryf in ‘n omvattende bestuursplan wat die effektiwiteit van die huidige bestuursaksies sal verbeter. iii

ABSTRACT.

Keywords: Vaal River Barrage reservoir, integrated resource management, impoundment management.

The Vaal River Barrage reservoir (VRBR) was constructed by Rand Water in 1923 for the purpose of ensuring an adequate raw water supply to meet the potable water requirements of the Pretoria, Witwatersrand and Vaal Triangle regions, and today this is still the main purpose of this body of water.

A number of different acts have reference to the management of the Barrage reservoir. These, together with Rand Water’s internal policies, are collated and described to provide a reference manual for the integrated management of the Vaal River Barrage reservoir. For completeness, all relevant policies are attached as appendices to the document.

Figure 1: Satellite image of the Vaal River Barrage catchment vi

Table of Contents. Page.

1. INTRODUCTION 1

2. PROBLEM STATEMENT 7

3. A HISTORY OF THE VAAL RIVER BARRAGE RESERVOIR 8 3.1 Water Quality 9 3.2 Pollution Control Powers 12

4. CATCHMENT MANAGEMENT IN RAND WATER 14 4.1 Area of Operation 15 4. 2 Approach and Technology 16 4.3 Catchment Management Agency development 17 4.3.1 Water Management Area 17 4.3.2 Catchment Executive Committees 18 4.3.3 Advisory Committees 20

5. LEGISLATION RELATED TO WATER RESOURC E MANAGEMENT IN SOUTH AFRICA 21 5.1 Rand Water Board Statues (Private) Act 17 of 1950 21 5.2 The Water Act (54) of 1956 24 5.3 The Water Services Act (108) of 1997 24 5.4 The National Water Act (36) of 1998 25 5.5 The Physical Planning Act 26 5.6 The Conservation of Agricultural Resources Act (43) of 1983 30 5.7 The Constitution of the Republic of South Africa, Act 200 of 1993 30 5.7 Environmental Conservation Act. Government Notice No 51, GG No 15428 of 21 January 1994 30 5.9 Water Laws Rationalisation and Amendment Act, No 32 of 1994 31 5.10 Development Facilitation Act, No 67 of 1995 32 vii

5.11 Reconstruction & Development Program (RDP) 32

6. WATER QUALITY MANAGEMENT IN THE VAAL RIVER BARRAGE RESERVOIR 34 6.1 Background Informa tion 34 6.2 Monitoring and Analyses 35 6.2.1 Selection of sampling sites 35 6.2.2 Selection of variables 37 6.3 Receiving Water Quality Objectives 41 6.3.1 The Role of Water Quality Objectives 42 6.3.2 Identification of Key Water Quality Objectives 43 6.3.3 Rand Water’s requirements for purification purposes 46 6.3.4 Department of Water Affairs & Forestry’s Objectives 47 6.3.5 Determination of Ideal Water Quality Requirements 47

7 WATER QUALITY STATUS OF THE VAAL RIVER BARRAGE RESERVOIR 54 7.1 Salinity 54 7.2 Eutrophication 57 7.3 Biological status 63 7.3.1 Microbiological 63 7.3.2 Hydrobiological 63 7.4 Physical Properties 67 7.5 Pollution events 68 7.5.1 Point Pollution Sources 69 7.5.2 Diffuse Pollution Sources 71

8 IMPOUNDMENT MANAGEMENT 73 8.1 Description of the Vaal River Scheme 73 8.1.1 Impounding Reservoir 73 8.1.2 The Barrage Structure 75 viii

8.1.3 The Barrage Gates 76 8.1.4 Technical Information 77

8.2 Management activities aimed at achieving the fitness for use of water in the Barrage reservoir 77

8.2.1 Routine monitoring of the reservoir 77 8.2.2 Problem centered monitoring 77

8.3 Development Control 78 8.3.1 The Vaal River Complex Guide Plan / Urban Structure Plan 78 8.3.2 Flood line protection 81 8.3.3 Sanitation systems evaluation 85

8.4 Reservoir Maintenance 86 8.4.1 Project Barley 86 8.4.2 Rand Water property (marginal strip) management 87 8.4.3 Aquatic weed control 86

8.5 Recreational activities control 89 8.5.1 Boat density control 89 8.5.2 Special sporting events control 92

8.6 Conservation 92

9. WATER QUANTITY CONTROL MEASURES 95 9.1 Weirs 95 9.2 Normal Operating procedures for the Barrage gates 95

10. INFORMATION MANAGEMENT 96 10.1 Modeling 96 ix

10.2 GIS & CIMDSS development 96

11. CUSTOMER FOCUS INITIATIVES 101 11.1 Education 101 11.2 Community involvement 101 11.2.1 Vaal River Safety Association 101 11.2.2 River Property Owners Association 101 11.2.3 Save the Vaal Environment 101 11.2.4 SAPS Water Wing 101 11.2.5 Boat Clubs & Hotels 101 11.2.6 Barrage Reservoir Forum 102

12. CONCLUSIONS 103

13. RECOMMENDATIONS 104

REFERENCES APPENDICES x

APPENDICES.

1. Rand Water’s raw water guidelines for operational purposes 2. Recreational water quality report 3. Annexure C of the Vaal River Complex Guide Plan 4. Rand Water’s guidelines for implementation of Annexure C 5. Definition of flood zones 6. Sanitary arrangements for development along the VRBR 7. Conditions for the use of Rand Water’s marginal strip 8. Regulations for boating on the VRBR 9. Rand Water’s powers to control boating 10. Procedure to apply for a boating permit 11. Operating procedures for the Barrage gates xi

LIST OF FIGURES. PAGE.

Figure: 1. Satellite image of the Barrage Catchment iv 2. Cost breakdown of Rand Water’s major expenses 3 3. Annual increase in raw water price 4 4. Catchment delineation of the Barrage reservoir 15 5. Upper Vaal Water Management Area: Sub -catchments 19 6. Management structure for the Upper Vaal Water Management Area 19 7. Electrical Conductivity changes from Lethabo weir to the Barrage 56 8. Phosphate changes from Lethabo weir to the Barrage 61 9. Nitrate changes from Lethabo weir to the Barrage 61 10. Algal biomass concentrations of the dominant species in the Barrage reservoir 66 11. Mean monthly chlorophyll-a values in the Barrage 66 12. Mean monthly Secchi disc readings in the Barrage reservoir 67 13. Mean monthly turbidity readings in the Barrage reservoir 68 14. Mean monthly COD values in the Barrage reservoir 68 15. Most critical point pollution sources in the Barrage catchment 70 16. Existing Guide plan restrictions 79 17. Proposed Guide plan restrictions 81 18. Proposed new policy for development within flood line 85 19. Daily outflow from the Barrage for the period October 2000 to October 2001 95 20. Example of CIMDSS statistics report 98 21. Example of CIMDS time series graph 99 22. Example of riparian property GIS database 100

xii

LIST OF TABLES. PAGE.

Table:

1. Original constituents analysed for in the monitoring programme 38 2. Variables selected for the Barrage reservoir monitoring programme 39 3. Variables selected for the Loch Vaal monitoring programme 40 4. Receiving water quality objectives – DWAF 47 5. Receiving water quality objectives – VBCEC 52 6. Components of the combined industrial salt load 54 7. Components of combined mining salt load in the Middle Vaal 55 8. Chlorophyll-a concentrations and dominant algal species in the Barrage 64 9. Average chlorophyll-a values for the Barrage reservoir 65 10. Chlorophyll-a concentrations and dominant algal species in the Loch Vaal 65 11. Average chlorophyll-a values in the Loch Vaal 65 12. Allocation of water stored in the Barrage reservoir 74 13. Dimensions of the Barrage reservoir 75 14. Particulars related to the construction of the Barrage 76

1. INTRODUCTION.

The history of most, if not all, of the world’s cities are intricately bound up with the need for and assurance of adequate water supplies. Ancient civilisations and cities had to give attention to water supply and man’s ingenuity may well have reached some of its greatest heights when surmounting water problems of the day. Relatively speaking, very few, if any, of our modern hydrological and water conservation and supply schemes eclipse the achievements of the ancients such as the Egyptians, the Romans and the Assyrians, to name but three (Laburn, 1979 a).

A study of an atlas will show that virtually all cities and towns of any size or consequence are located close to fresh water supplies. Natural resources could not be exploited to any great extent if an assured and adequate supply of water was not relatively close by.

The Witwatersrand is not so situated, yet it has developed in a remarkable manner. Water could certainly have been a great limiting fa ctor to its growth and development – but in spite of several inherent geographical difficulties adequate supplies of water have in fact been available since the Rand Water Board was created to cater for the region (Laburn, 1979a).

For obvious reasons the Vaal river has been called “Africa’s hardest-working river” and the “main artery of the South African heartland”. The Vaal River water supply area is by far the most important supply region in South Africa. Already in 1975 it produced 55% of the country’s gross domestic product and housed 42% of the urban population of South Africa. The mining production in the Vaal river catchment represented 79% of South Africa’s total. Even from an agricultural point of view the Vaal River catchment is vital, yielding 42% of the country’s agricultural produce. Furthermore a total 155 000 ha of land are irrigated from the Vaal River and its tributaries (1986). Besides this, most of the country’s power stations and oil-from-coal industries are situated in the upper Vaal catchment (Braune, 1986).

The Rand Water Board was constituted by the Rand Water Board Incorporation Ordinance 1903 (Transvaal) (Ordinance No. 32 in May, 1903) that was assented to by the Governor on 8 May, 2

1903. This Ordinance provided for the formulation of a scheme or schemes for supplying the area and of entering into agreements to supply water in bulk (Laburn, 1979a).

Further powers were subsequently granted to the Board by various Ordinances and Acts which, with the two Ordinances mentioned above, were cited comprehensively as the Rand Water Board Statutes 1903-1949. This legislation was consolidated as the Rand Water Board Statutes (Private) Act, 1950 (Act No. 17 of 1950) (Laburn, 1979a).

The Board was modeled on the then recently established Metropolitan Water Board in London, and thrived on the challenge of meeting the rapidly increasing demand for water (Laburn, 1973). In 1905, the first year of full operation, the population of Johannesburg was estimated at between 150 000 and 200 000 with the average consumption of water per European being 75 liters per day and 28 liters per non-European (Laburn, 1979a). In 1973, the average annual daily quantity supplied was 1 334 Ml/day, with a peak day demand of 1 700 Ml/day. At the time it was estimated that by the year 2000 the demand would be in the order of 5 000 Ml/day, serving a population between 10 and 12 million (Laburn, 1973). In 2000, the average daily consumption was 2 940 Ml/d (Rand Water, 2001a).

Prior to 1966, the Barrage was the major raw water source of Rand Water. As a result of increasing pollution of the Barrage, less water being released from Vaal Dam and the deterioration of water quality in the Barrage, less water is being abstracted from the Barrage and more from the Vaal Dam. It is necessary, therefore, to protect the Vaal Dam water from being polluted and important to protect the water of the Barrage from further deterioration as users downstream are adversely affected (DWAF & RW, 1993).

Although Rand Water presently abstracts less than 2 percent of its water requirements from the Vaal 3

River Barrage Reservoir it is an important source of potable water for the lower Vaal and much sought after for recreation. The monetary value of fixed properties riparian to the Vaal River Barrage reservoir and money spend by people for recreational purposes amount to several millions of Rand per annum.

The deterioration in water quality of the Vaal River Barrage reservoir can affect the personal preferences of people with regard to the aesthetic value of the reservoir which may lead to a reduction in property values and recreational usage of the reservoir with associated financial losses to the local economy.

More recently, concern was expressed regarding health related water quality variables in the Barrage reservoir water as a result of the frequent sewage discharges of sub -standard quality into the catchment.

One of Rand Water’s most valuable assets is its raw water. Cost to obtain raw water from the Department of Water Affairs and Forestry amounts to almost 50% of Rand Water’s annual budget expenditure (Figure 2). This amounted to R 856 million for the financial year 1999/2000 Rand Water, 2001a). This figure is expected to increase consistently in future, as recent trends illustrate (Figure 3).

Raw Water 46.3%

Chemicals 3.5%

Energy Other 10.1% 15.6%

Finance Charges 7.5% Emoluments 18%

Figure 2: Cost of raw water in relation to other expenses.

If the raw water quality in the Vaal River Barrage reservoir and Vaal Dam catchments deteriorates beyond a certain level, increased purification costs will be inevitable, the ecology will be severely impacted and the aesthetic and recreational value will be reduced (DWAF & RW, 1993). The only manner in which these resources can be safeguarded is to manage those aspects in the respective source water catchments that could adversely affect the quality of the raw water.

120

100

Cents / kl 40

1981 1982 1983 1884 1985 1986 1987 1988 1889 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 Years

Figure 3: Annual increase in raw water price.

The quality of the water in the Vaal Dam is generally described as low electrolytic and turbid, whereas the water of the Vaal River Barrage reservoir is the exact opposite in that it is relatively clear and eutrophied with a high mineral content. Pollution emanating from the highly industrialised and urbanised southern Gauteng is responsible for this marked deterioration of the water quality in the Barrage reservoir.

The Barrage reservoir drains a densely populated, highly industrialised and extensively mined area. Return flow emanating from this catchment has resulted in a deterioration of the water quality in the reservoir. Although Rand Water's extensive water quality monitoring and pollution abatement program is principally aimed at protecting it's raw water sources for potable purposes, it also fulfils 5 the equally important function of protecting the aquatic environment, thereby securing a sustainable raw water supply.

The Vaal River Barrage catchment covers 4,5 % of the total Vaal River catchment and contributes 7,8 % of the total mean annual runoff (MAR) of the catchment. Situated in this catchment are about 13 600 wet industries (Swart, 1999), 21 wastewater treatment works and a number of working mines, while the population of the area is estimated to be around 10 million (more than 600/km2), making it one of the most densely populated areas in the country.

In the last 15-20 years increasing demands on our limited water resources and increasing pollution of these resources (especially in terms of dissolved salts) have been great cause for concern in South Africa. Demands have been particularly great in the Vaal River Barrage and Middle Vaal catchment areas, largely as a result of rapidly increasing urbanisation and growing industrial and mining activity (SRK, 1993).

Eutrophication related water purification and water quality problems experienced by Rand Water also coincides with an increased Klip:Vaal ratio. Research indicated that if the Klip:Vaal ratio exceeds 2:1, long residence times, high conductivities, high nutrient concentrations and low turbidities are recorded. These conditions in the Vaal River Barrage Reservoir contribute to algal blooms. Chlorophyll values in excess of 30 mg/l in the untreated water normally results in chlorophyll concentrations in excess of the 1 mg/l chlorophyll guideline value set by Rand Water for potable water (DWAF & RW, 1993).

Investigations by Rand Water on the effective control of algae and the algal related problems at Rand Water’s purification plants, indicated that the additional purification cost due to the implementation of sophisticated technologies necessary to avert eutrophication related problems could vary from 0,13c/kl to 9,9c/kl (1988 rates). During 1999, Rand Water constructed an activated carbon plant at a cost of R 22 million. Running this plant during periods of high algal occurrence, will increase the purification cost from the normal 4 cents/kl to around 11c/kl.

A survey done by Rand Water in 1992 indicated up to 6 105 sewer blockages a year in well 6 controlled areas of the catchment, of which 612 were major blockages. These blockages were usually repaired within 24 hours with little if any raw sewage reaching the tributaries. In other areas, where an efficient sewer maintenance programme was lacking, an estimated 60 Ml/d of raw sewage was discharged into the catchment, of which about 50 Ml/d reached the tributaries of the Barrage reservoir. Fortunately, the situation improved over the next four years (up to 1996), whereafter a slow deterioration in systems maintenance has again been observed.

Results from analyses conducted in the Loch Vaal catchment clearly indicated that water in the Rietspruit is for the greater part not suitable for potable, recreational or agricultural purposes. This situation is however not unique for the Loch Vaal catchment. Algal scums in Loch Vaal are incorrectly perceived by the public to be raw sewage whilst various complaints are received about submerged vegetation obstructing boating (DWAF & RW, 1993). Water entering the Vaal River Barrage reservoir from the Klip River catchment frequently contains high bacteria concentrations and high numbers of pathogenic protozoa. The presence of these indicators of faecal pollution may be explained by the estimated 20 to 30 Ml/d discharge of raw sewage into the Klip River catchment, or conversely, high volumes of treated sewage constantly being discharged into the rivers.

If the hydrology of the Vaal River Barrage catchment is studied, it will be seen that under dry weather conditions the Klip River catchment contributes more than 90 % of the flow to the Barrage and of that flow, the major portion is purified sewage (about 89%) originating from 7 of the 21 wastewater reclamation plants in the Barrage catchment.

Mineralisation of waters in the tributaries of the Vaal River Barrage is also an important factor, but if trends in the Klip River are studied, there has been no recent increase in the mineralisation of this tributary. By far the most pressing problem is the microbiological status of the tributaries of the Barrage catchment and all resources should be directed in an effort to find a solution to this problem (DWAF & RW, 1993). 7

2. PROBLEM STATEMENT.

Problems experienced with the management of the Vaal River Barrage reservoir are for the greater part due to the complexity of the catchment and the large number of role players within the area. This, in the past has often resulted in fragmented and inconsistent application of regulations causing frustration and confusion within Rand Water, DWAF, the public sector and industry. It is considered in the best interest of all role players that this situation be remedied.

From the introduction it is clear that the water quality of the Vaal River Barrage reservoir and its tributaries do not comply with set quality guidelines at all times and it is therefore essential that these water bodies are managed on a sustainable basis.

Starting with a historic overview of Rand Water and the construction of the Barrage, the purpose of this study is to outline all activities currently undertaken by Rand Water in an attempt to optimise the efficiency of the management of the reservoir for the benefit of all its identified users. 8

3. A HISTORY OF THE VAAL RIVER BARRAGE RESERVOIR.

By 1900, less than 15 years since the discovery of gold on the Witwatersrand, all the local supplies of water, both surface an underground – except for one dolomitic source – either failed or were inadequate to meet the rapidly increasing demand (Laburn, 1978).

On 1 April 1905, the Board officially took over the responsibility of supplying water to the Witwatersrand and the operation and maintenance of the installations of the Johannesburg Water Works Estate & Exploration Company Limited, the Braamfontein Company, the Vierfontein Syndicate and the Wonderfontein Concession.

By far the largest and most reliable source of water was from the Zuurbekom wells, which yielded an average of 9,5 Ml/day during the year ending 31 March 1906 (Laburn, 1979a). It is a mystery that the major river of the region, the Vaal River, was apparently not considered as a possible source to augment the Zuurbekom wells. One possible reason is that the river was an “international” river between the (former) republics of the Transvaal and Free State, with possible political problems preventing its exploitation.

In 1914 the Board, after considering several schemes that included 58 investigated by the Chief Engineer, finally adopted the Vaal River Development Scheme that involved the construction of the Barrage, the provision of a purification and pumping works at Vereeniging and the establishment of a pipeline extension to Zwartkoppies. The Barrage reservoir, deriving water from the Vaal and the four tributaries flowing into the Barrage, would be capable of yielding 91 Ml/day but all the other development works were for the first stage of 45,5 Ml/day only (Laburn, 19791).

Shortly after the approval of the Scheme, the 1914-1918 World War I broke out, which delayed the construction of the Barrage. Construction eventually started in July 1916 and the structure was completed in December 1922. The first phase of the Scheme cost R 3 050 000 and yielded 22,7 Ml/day. The second stage was proceeded with immediately afterwards at a cost of R 1 000 000 (Laburn, 1979a). 9

The Vaal River Development Scheme was the first major development scheme undertaken on the Vaal River which, prior to 1923 and the Barrage impoundment, was an intermittent river at Vereeniging (Laburn, 1979a).

The original width of the Vaal River at the Barrage site was 190m. The Barrage structure was fixed at 427m so that no question could arise in future in regard to the obstruction of the natural flow of the river during high floods. With the assured supply from the Vaal river the Board was able to close down several of its local sources to the west of Johannesburg (Laburn, 1979a).

The demand for water rose from a paltry 8 Ml/d in 1904 to 1 755 Ml/d in 1975 (Laburn, 1978). The average daily quantity supplied by the Board in 1978 was 1 890 Ml/d, and it was expected at the time that by the turn of the century 6 000 Ml/d will be consumed (Laburn, 1979b).

The Vaal Dam was constructed in 1934 at a cost of R 3,3 million by the Department of Water Affairs and Forestry. The Rand Water Board contributed R 2,4 million (72%) towards the cost of the dam for the right to abstract, in perpetuity, 886 470 m3 of water per day from the dam without further payment (Laburn, 1979b).

The impounding of water in the Vaal Dam, effectively commenced in November 1937, and had the effect of smoothing out variations in the turbidity of the water in the Vaal Barrage and the river downstream of the Dam, even at times of floods. The water did not carry such high quantities of suspended matter as in the years before the existence of the Dam: on the other hand, the water was not as clear and free from turbidity during the winter/spring period to the extent that had previously been the case (Laburn, 1979a).

3.1 Water Quality

One of the earliest mentions of pollution was made in 1929 and arose from the fact that Rand Mines Power Supply Co. Ltd. abstracted water from the Barrage reservoir for a power station and discharged warmer water into the Barrage upstream of the Board’s intake station. Thermal pollution 10 was feared but settlement was achieved with Rand Mines paying the Board R7 200.00 per annum to fund additional works that would be necessary to ensure the efficient operation of the sedimentation system (Laburn, 1979a).

In resorting to the Vaal river and its water stored in the Barrage reservoir the Board realised that attention had to be paid to the treatment and purification of the raw water from surface run-off before it could safely be put into supply. The turbidity of the Vaal’s water, a persistent and in many respects a peculiar characteristic of this river, was obviously the greatest problem (Laburn, 1979a).

By a queer twist of fortune, the Barrage was by 1973 already a storage reservoir causing embarrassment and difficulties as far as the quality of the water was concerned (Laburn, 1973). To illustrate this point, the number of days per annum that the water after treatment at Vereeniging pumping station did not comply with the maximum permissible TDS has increased from virtually 0 in 1962 to 168 in 1978 (Laburn, 1979c). From those early years, the main sources of pollution were identified as sewage effluents, underground water pumped by the gold mines, and surface pollution that is washed or dumped into streams.

The impact of anthropogenic activities on the water environment was recognised many years ago, as reported by Laburn (1973); “… industrial and economic growth causes manipulation of the traditional or natural environment. The environment can and does suffer damage by man, particularly when and where he decides to congregate and live in large numbers”.

About two thirds of the total water supplied by Rand Water is returned via the local authorities’ wastewater treatment plants and/or tributaries back into the Vaal River Barrage reservoir (Laburn, 1978). “While this return flow is beneficial quantitatively, considerable qualitative problems arise that are becoming increasingly felt as more and more water is abstracted from the Vaal and proportionately less is passed downstream of the Vaal River Barrage” (Laburn, 1978). “Clean rivers must not be allowed to deteriorate unduly” (Laburn, 1978).

The quantity of effluent discharged by local authorities into the Klip River amounted to 500 Ml/day in 1979, constituting 30% of the total flow in the river (Laburn, 1979a). Laburn (1979a) also 11 reported wastewater treatment works in the seventies to be of insufficient capacity to cope with the load placed upon them. Since 1938 and particularly after 1956/7, following the raising of Vaal Dam’s wall, the flow rates of the discharge from the dam have not always coincided with that of the Suikerboschrant and Klip rivers. Thus when the tributaries were flowing strongly with relatively high salinity water, the discharge from the Vaal Dam was restricted, and consequently little dilution of the tributary water took place in the reservoir (Laburn, 1973).

The Water Research Commission, (1979) calculated the total salt load into the Barrage reservoir over the period September 1977 to August 1978 to be 893 000 tons. A 1995 study (Pulles, Howard & de Lange, and Stewart Scott) indicated this figure to be 677 000 tons.

The quantity of underground water abstracted and dis charged diminished from 170 Ml/d in 1956 to 76 Ml/d in 1972, and then increased again to 120 Ml/d in 1977, as a result of renewed gold mining activities (Laburn, 1979a).

During the early days of operation the Board became aware of the fact that the water quality in the Barrage was deteriorating. In 1949 a decision was made to construct a new purification works (Zuikerbosch) in such a position that raw water would be abstracted upstream of the troublesome tributaries. This was followed by a decision in 1965 to provide a pipeline bringing water directly from Vaal Dam, because, as a result of the increasing draw-off from Zuikerbosch, poorer quality water from the Klip and Suikerboschrant rivers were being drawn upstream into the intakes at Zuikerbosch (Laburn, 1979a).

By 1973, the average sulphate concentration in the Klip river (average flow 4,8 m3/sec) was 460 mg/l, and in the Suikerboschrant river (average flow 5,0 m3/sec), it was 235 mg/l. In 2000, the average flow in the Klip River was 24 m3/s, and the sulphate concentration 190 mg/l, while the average daily flow in the Suikerboschrant River was 11m3/s and the sulphate concentration 436 mg/l. The dosage of chlorine necessary to disinfect the water prior to putting it into service trebled in 30 years between 1943 and 1973 (Laburn, 1973).

The Board’s pro-active measures taken during these early years resulted in a good understanding of the dynamics of the Barrage catchment, which was summarised as follows by the chief Engineer, R. J. Laburn, in 1979a; “Fortunately the quality of Vaal Dam water is excellent and should remain so for many years, but the future of the Barrage is neither so clear nor encouraging. Alas, a series of aggravating factors prevail. Firstly, ... the proportion of effluent in the tributaries is rising. Secondly,… less water is being discharged from Vaal Dam, ... therefore, the Barrage often recieves more water from the tributaries … than from Vaal Dam. Thirdly, the nature of the contents of effluents from urban and industrial sources and from agriculture is changing”.

3.2 Pollution Control powers

With remarkable foresight of the problem that would confront the Board several decades later, the Board’s Act provided very adequately for pollution control in the water courses of streams feeding into the Barrage reservoir. It is clear that the motive of the original Ordinance of 1903 was the need for establishing a body with wide powers as far as water supply was concerned, realising that unless so ably armed or empowered, essential supplies of water could be polluted or spoilt at source (Laburn, 1979a).

Since 1904, the Rand Water Board has had powers to control pollution, and since 1914 it has had powers to control pollution in the Vaal River Barrage reservoir such that any water from a river source flowing into the Barrage reservoir may be controlled, and any source of contamination or pollution can be arrested in terms of the Board’s Statutes. The practical effect of these rights has been that the discharge of sewage effluent directly into streams or tributaries situated within 32 kilometers of the Vaal River Barrage has been prohibited: the sewage must be treated in a manner approved by the Board and thereafter disposed of by means other than direct disposal into the stream. This policy has ensured that the quality in the Barrage remained reasonably satisfactory for many years since 1923. With the increase in return flow, and the increase in industrialization on the Witwatersrand and in the area surrounding or adjacent to the Barrage, this policy has had to be enforced more and more rigorously since the early seventies. It became apparent that, consistent with its Statutes, The Board had to investigate the sources of pollution beyond the 32 kilometers 13 limit set by itself. This involved the measuring of the quantity and quality of water being discharged into the streams and rivulets. “Only when complete records and information have been established can the problem be tackled comprehensively and in the best manner” (Laburn, 1973).

As early as 1943 the Chief Engineer drew the Board’s attention to the need for pollution control and the need for proper and effective control and management (Laburn, 1973, and 1979a). Had the Board not exercised realistic monitoring and pollution control measures some of the effluents from local authorities’ treatment works would have been chronically of sub -standard quality (Laburn, 1978). Laburn (1978) also argued that water pollution be kept within the strictest possible limits, and that this could best be done by the body most directly concerned, namely the regional water supply authority.

A sound provision that was included in the Vaal River Development Act of 1914 and later became Clause 139 of the Rand Water Board Statutes (Private) Act No. 17 of 1950 was that for the prevention of, and penalty for, pollution of water. Not only did this empower the Board to control all pollution within eight kilometers of the Barrage reservoir, but it empowered it to exercise control of water pollution on any gathering ground, watercourse, spruit, stream or river leading into the Barrage reservoir, i.e. the entire catchment of the Vaal River upstream of the Vaal River Barrage. The Act wisely and fortuitously made provision for suitable action to be taken by the Board in cases not only where pollution was actually being caused but in cases where pollution was likely to be caused (Laburn, 1979a).

Although the previous Water Act, (54 of 1956) placed the responsibility of ensuring adequate supplies of raw water with the Department of Water Affairs and Forestry, the Rand Water Board Statutes (Private) Act remained in force. The Statutes were eventually repealed with the promulgation of the Water Services Act 108 of 1997, and the National Water Act, 36 of 1998.

Rand Water over the years remained intimately and deeply concerned with the quality of water in the Vaal River and more particularly in the Vaal River Barrage reservoir, from whence much of the 14 raw water required by it was abstracted. Chapter Four describers Rand Water’s activities and approach to protect this important resource.

4. CATCHMENT MANAGEMENT IN RAND WATER.

The overall goal of Rand Water's catchment management activities is to protect its source waters by minimising the deterioration in quality of the raw water supply that is needed to supply high quality potable water. Catchment management, therefore, is directly consequential to Rand Water's mission statement of ensuring a consistent and reliable supply of potable water, and to promote the need for an improved quality of water in rivers and reservoirs by being actively involved in the total management of water in its region.

Until 1968 the control exercised by the Board over pollution in the catchment took the form of prohibiting the discharge of any effluent into any stream that fed, either directly or indirectly, into the Barrage reservoir. This meant that, within the given radius, all effluents had to be disposed of by irrigation onto land. However, the 32km control distance did not extend into the areas of the Witwatersrand where the great majority of the pollution emanated. Stricter and more widespread control became necessary and before the specific sources of pollution could be traced, it was necessary to erect or construct some 40 weirs and some 74 control points at key points on the streams and tributaries flowing into the Barrage. These weirs were constructed between 1970 and 1974 (Laburn, 1979a, and 1973).

Rand Water’s primary business driver is to supply drinking water that is safe, affordable and pleasant tasting. The organisation has adopted a holistic approach and has an integrated water resource strategy which includes a comprehensive and dedicated catchment management programme to protect and monitor the sources of water supply. The strategy is regarded as Rand Water’s “insurance” on investment to protect the organisation’s largest asset which is the raw water purchased from the Department of Water Affairs and Forestry (Figure 2).

Rand Water’s catchment management programme is proactive with the starting point being that a deterioration of the raw water quality, will inevitably lead to increased purification costs. As the quality of the raw surface or river water is continually influenced by the changing geological formations, and both natural and man influenced landscapes through which the rivers flow on their 16 journeys from source to the sea, an understanding of the shifting environmental characteristics are vital to Rand Water’s catchment management programme. The programme consequently includes a wide range of activities from monitoring all major rivers and dams, routine water sampling and control over boating to long term projects such as pollution and erosion control, the removal of alien or nuisance vegetation and wetland rehabilitation.

4.1 Area of Operation.

Rand Water maintains an extensive water quality monitoring programme covering an area of 47 119 km2 which includes both the Vaal Dam and Vaal River Barrage Reservoir catchments. The Barrage reservoir catchment covers about 9 000km2 (Figure 4).

Towns Rivers

Barrage Catchment Sub-catchments

Figure 4: Catchment delineation of the Barrage Reservoir

Water quality analyses are undertaken at state-of-the-art laboratories and include inorganic, organic, microbiological, biological and radioactive water quality variables (Tables 2, 3,and 5). Where effluent discharge permit standards are exceeded or pollution is evident the staff of Rand Water’s Catchment Management section interacts with the necessary authorities or industries to remedy these problems.

4.2 Approach and te chnology.

Rand Water’s catchment management program is a proactive intervention aimed at accommodating anticipated changes in water quality and quantity. Rand Water therefore follows an integrated catchment management approach, with emphasis on a combined effort with all stakeholders to prevent pollution rather than to act in a remedial manner. Data on all aspects of the environment is collected and stored on computerised databases for quick and informed decision making. These databases are custom designed to allow for simple operational efficiency in terms of statistical analysis of data.

Municipal sewage works, factories, mines, resorts, animal feed lots, irrigated land, refuse dumps and other potential sources of polluted effluents and run-off are inspected on a regular basis. Action is taken when significant variations in water quality from set standards are observed. Treated effluent from sewage purification works is discharged either directly or indirectly via tributaries into the Barrage reservoir. These sewage works are visited and monitored regularly to assist with, and advise on, effluent quality variations.

Boats used for river and dam sampling make extensive use of a combination of Global Positioning Systems (GPS) and echo sounder technology to locate optimum sampling sites. Boats are also used for patrol work as Rand Water controls the number of boats using the Vaal River Barrage reservoir for recreational purposes and full use is made of laptop and palmtop computers, cellular telephones and on-site water quality test kits.

Systematic aerial surveys are undertaken at regular intervals to locate and identify sources of pollution in heavily urbanised and inaccessible areas. A GPS is again used to pinpoint these locations 18 for mapping and follow up inspections by a ground crew. Aerial surveys provide a different dimension for gathering information regarding problem areas and pollution incidents in the catchment, and together with video camera equipment, full use is made of state of the art technology.

4.3 Catchment Management Agencies

The process and procedures for the establishment of Catchment Management Agencies (CMA’s) are clearly explained in Chapter 7 of the National Water Act (Act 36 of 1998), with the management guidelines provided in Schedule 4 of the same Act (DWAF, 2001).

The requirements for public involvement, consultation and participation have been clearly indicated in the National Water Act (NWA). The foundation for the entire process of establishing a CMA has been based on stakeho lder involvement. This implies that any interested and affected party within a catchment where the process of CMA establishment is contemplated must be able to provide input into the process, and all the contributions that are obtained must be considered. This ensures that the concept of transparency is maintained (DWAF, 2001).

While the NWA places great emphasis on the importance of public participation and representivity, it does not make any specific reference to the establishment and functioning of Catchment Forums. However, the mere fact that emphasis is placed on the need for participation and representivity implies that the existence of Catchment Forums is a very important factor in the entire CMA process. While the Catchment Forums cannot be statutory bodies in terms of the NWA, the roles and functions of a specific forum can be clearly stated in the form of a charter bearing the signatures of relevant Chairpersons of the Forum and the Forum Management Committees (DWAF, 2001).

4.3.1 Water Management Area

In order to facilitate the CMA process, the Upper Vaal Water Management Area was divided into three management units due to the complexity of the area. The essential concept behind the division was simply to make the management of the process easie r and to ensure that all the relevant parties in the area would be able to take an active part in the process. 19

In line with the requirements of the National Water Act, the management of this drainage system has been devolved to the interested and affected parties within the catchment under the guidance of the Gauteng Regional Offices of the Department of Water Affairs and Forestry. Each of these sub- catchments (Figure 5) are governed by an Executive Catchment Committee which in turn is made up of the members selected from the River forums in each of the sub-catchments (Figure 6).

Once the management units and the associated forums had been established, the CMA process required the formation of Catchment Executive Committees.

The Vaal River Barrage catchme nt forms an obvious management unit. It also serves as a source of water for users in the strategic Gauteng area, as well as for downstream users dependent on the Middle Vaal River for their water supply. This water body may need to be divided into two management units, namely upstream and downstream of the Lethabo weir, since this weir was specifically constructed to secure a low salinity raw water supply for sensitive industries and for blending at Rand Water’s Vereeniging purification works (DWAF & RW, 1996).

4.3.2 Catchment Executive Committees

Catchment Executive Committees (CEC’s) are essentially a consolidation of the various forums in each management unit. Each CEC consists of representatives from all stakeholder bodies and is roughly constituted of 15 to 20 members.

The three CEC’s in turn, is consolidated into the Upper Vaal Reference Group, established in August 2001. The primary functions of the Reference Group will be; · The development of a Catchment Management Strategy · The development of a terms of reference for the appointment of consultants

· The appointment of consultants for the development of Proposal and for public participation

· The development of a proposal for the establishment of the CMA, which will in turn be

forwarded to the Minister for approval · The co-ordination of the activities of the CEC’s 20

· The delegation of certain functions to the CEC’s. The Reference Group will have the power to assess the capabilities of the respective CEC and delegate certain tasks to a specific CEC.

Kromdraai Catchment

Barrage catchment

Vaal Dam catchment

Figure 5: Upper Vaal Water Management Area: Sub-catchments.

Upper Vaal CMA

Upper Vaal Reference Group

Upper Vaal Vaal Barrage Kromdraai CEC CEC CEC

Vaal Dam Wilge River Grootdraai Waterval Suikerbos Klip River Barrage Rietspruit Leeu/Taaibos Mooi River Loop Spruit Upper Lower Reservoir FMC Dam FMC Blesbok FMC Reservoir FMC FMC FMC FMC Wonderfontein Wonderfontein FMC FMC FMC FMC FMC FMC

Suikerbos Klip River Barrage Rietspruit Leeu/Taaibos Vaal Dam Wilge River Grootdraai Waterval Mooi River Loop Spruit Upper Lower Blesbok Forum Reservoir Forum Forum Reservoir Forum Dam Forum Forum Forum Wonderfontein Wonderfontein Forum Forum Forum Forum Forum Forum 21

Figure 6: Management structure of the Upper Vaal Water Management Area.

4.3.3 Advisory Committees

Section 81 of the National Water Act requires that an Advisory Committee must be established to make recommendations on the composition of the Governing Board of the CMA. The establishment of the Advisory Committee is therefore compulsory and is an independent statutory body.

The National Water Act, however, is not the only Act relevant to the management of the Barrage reservoir. Chapter Five investigates the various pieces of legislation pertinent to the management of the Barrage reservoir. 22

5. LEGISLATION RELATED TO WATER RESOURCE MANAGEMENT IN SOUTH AFRICA.

The new constitutional and political dispensation after April 1994 brought about a change in approach and thinking regarding quality management issues, including water quality management. This new management framework demanded of every institution to re-evaluate, re-think, re-plan and re-design its existing basic approach and the management systems already in place.

Perhaps the earliest attempts to manage water quality in South Africa were tribal laws that governed where people should take water for drinking purposes, should bathe and should water their livestock. This simple approach to water quality management had the advantage that it was community-based, was easily understood, was implemented by the entire community in their day-today livelihood, and the benefits accrued to those responsible for implementation (advantages which a number of policies are striving to achieve even today). However, this simple approach, in spite of its advantages, is clearly inappropriate for a modern South Africa, with many more communities scattered along its rivers, and with a host of other activities contributing to the overall pollution load (DWAF, 1999).

The decision in 1994 to revise the water law in SA, to bring it in line with the constitutional requirements for equity, provided the opportunity to completely revise the policy and subsequently the legislation governing water quality management (DWAF, 1999).

5.1 Rand Water Board Statutes, (Private) Act 17 of 1950.

Rand Water was originally established in terms of the Rand Water Board Incorporation Ordinance, Ordinance number 32 of 1903 (Transvaal), and eventually consolidated in terms of the Rand Water Board Statutes (Private) Act, Act Number 17 of 1950.

Rand Water originally derived its powers to have control over the water in the Barrage Reservoir in terms of the provisions of Section 128(a) of the Rand Water Board Act, 17 of 1950 (“the 23

Statutes”). The “works” as referred to in Section 128(a), is defined in the Eighth Schedule to the

Statutes as the area 39 miles (62,4 kilometres) upstream from the barrage wall

In terms of the Rand Water Act, Rand Water is the owner of the riverbed and adjacent portions of the riparian land along the Vaal River Barrage reservoir, for approximately 26 kilometres upstream of the Barrage wall. Upstream of the aforesaid 26 km, Rand Water acquired servitudes over certain areas of land, in order to store water.

In terms of Section 128 of the Rand Water Act, the following rigths were conferred on Rand Water; “Subject to the provisions of this chapter and to the due exercise by any owner of the rights conferred by permit under Section 125 the Board shall have the sole and exclusive right to take, abstract and use all water which it may take, intercept, dam, impound and store under powers conferred by this chapter, whether or not any such waters shall mingle after being stored with any other water of the said river, and shall, subject to all rights existing as at 29 th day of June 1914, have control over the area covered by the said works”.

In terms of Schedule B of the Rand Water Act, “the works” encompassed the entire Barrage reservoir. Rand Water therefore has, by virtue of not only the Rand Water Act, but also the common law, the power to control and protect its land and rights thereto, and the water contained thereon.

Section 139 of Rand Water's statutes provided definite protection against pollution of the reservoir in that it prohibited the deposition in or near any watercourse, spruit, stream or river directly leading into or communicating with the reservoir; any solid or liquid sewerage, trade refuse or domestic refuse which may have cause or were likely to cause pollution of the impounded water.

This Act has provided Rand Water with the means of imposing water quality limits which are more stringent than those legisla ted under the Water Act, 54 of 1956, as amended in 1982.

This Act was repealed with the enactment of the Water Services Act in 1997. In terms of the provisions of Section 84(2)((b) of the Water Services Act, Rand Water continues to exist and is 24 deemed to be a water board established in terms of the Water Services Act, despite the Statutes being repealed partially in terms thereof and in whole in terms of the National Water Act.

In terms of the provisions of Section 84(3) of the Water Services Act, the governance, name and service area of Water Boards, and therefore Rand Water, remain as defined in the Statutes, in terms of which Rand Water had been established, until such time as the Minister of Water Affairs and Forestry determines otherwise by notice in the Gazette.

In terms of the provisions of Section 84(4) of the Water Services Act, all existing rights and obligations of Rand Water remain in force.

· It is accordingly Rand Water’s contention that it retained all the powers, rights and obligations that it had prior to the commencement of the Water Services Act and the National Water Act.

· The Minister has not determined otherwise in terms of the provisions of Section 84(3) of the Water Services Act by notice in the Gazette, with the result that both the Minister and Rand Water believes that Rand Water is empowered to exercise the necessary control and governance over that portion of the water that falls under its jurisdiction. Indeed, Rand Water is legally obliged to do so.

The Minister has recently confirmed that it continues to rely on Rand Water, to ensure inter alia that the Barrage is used, managed and controlled in terms of Rand Water’s powers of governance.

Chapter VI of the Statutes relates to Rand Water’s power to impound water in the Vaal Rive r and matters incidental thereto.

· One of those powers is the power to maintain the Barrage. · All of Rand Water’s powers relating to the use, maintenance and repair of the Barrage, however, is subject to the primary, secondary and tertiary use of water by riparian landowners.

Section 11 of the Irrigation and Conservation of Waters Act, Act No. 8 of 1912, defines primary use as “ use necessary for the support of animal life … and … domestic purposes …” Secondary use is defined as “… use for the irrigation of land; and tertiary use is defined as “… use for mechanical and industrial purposes…”

5.2 The Water Act, 54 of 1956

By the early 1950’s, growing demands for water made it clear that effluent reuse would have to be considered. This lead to the promulgation of the Water Act of 1956 (Act 54 of 1956) which required that all effluent had to be returned to the water body from which it was originally abstracted. The provisions of the Act highlighted a number of important issues. Most importantly, recognising tha t effluent returned to the water environment could lead to a deterioration in water quality, this act required that all effluent comply with certain given standards. These standards were promulgated in 1958, and required that all effluent comply to Uniform Effluent Standards, which comprised the General Effluent Standard, the Special Standard and later the Special Standard for Phosphate. Discharge permits were only issued in cases where the applicable standard from the above list would be exceeded (DWAF, 1999).

With respect to the Barrage reservoir, the main disadvantage of this Act was that it did not allow for specifying different standards for sources where the volume of effluent, number of pollution sources, or use of the water warranted more stringent water quality management.

The regulations promulgated under the Water Act, 54 of 1956, as amended in 1982 in respect of phosphate concentrations in certain sensitive catchments, provides definite numeric limits for a variety of water quality variables dis charged into natural drainage systems.

5.3 The Water Services Act (108) of 1997

Section 30 of the Water Services Act provides for Water Boards to undertake catchment management activities subject to the following conditions;

30(1)A water board may perfo rm an activity other than its primary activity only if-

(a) it is not likely to limit the water board’s capacity to perform its primary activity; (b) it is not likely to be the financial prejudice to itself, any water services institution, existing consumers and other users serviced by its service areas; (c) it is in accordance to the board’s policy statement; and (d) it is provided for in a business plan.

(2) Other activities that a water board may perform include, but are not limited to-

(a) providing management services, training and other support services to water services institutions, in order to promote co-operation in the provision of water services; (b) provide catchment management services to or on behalf of the responsible authority; (c) perform water conservation functions.

Clause (2)(b) and (c), together with (1)(c) an (d) therefore clearly allows for Rand Water to continue with its water resource protection activities in the catchments of the Barrage Reservoir and Vaal Dam.

5.4 The National Water Act (36) of 1998

The promulgation of the National Water Act, Act 36 of 1998 has heralded a new era in the South African water industry with the introduction of concepts such as Water Management Areas, Catchment Management Agencies, Integrated Catchment Management and Catchment Forums (Rand Water, 2001).

Although not explicitly stated in the Constitution, water is considered a national issue. The official viewpoint of the Department of Water Affairs and Forestry is that water, water pollution and its control is a national issue and, hence, falls under its control and jurisdiction, which will only be managed and administered by the Department. 27

The most important aspects of the Act, which stemmed from the White Paper on a National Water Policy for South Africa (1997), are the requirements to ensure environmentally friendly sustainable use of water resources, but also the need to ensure protection of the resource for the optimum social and economic benefit of the country. Coupled with these was the need for a transparent and participative approach to water resource management, and the need to provide for the “reserve”, which is the quality and quantity required for basic human needs and to maintain the sustainability of the aquatic ecosystem (DWAF, 1999).

The new act also provides for resource directed and source directed measures. Resource-directed measures aim to provide an appropriate level of protection for different water resources. This will be done within a water resources classification system – pristine to highly degraded. The classification will also establish Resource Quality Objectives for each water resource. This is done in terms of the requirements of the Reserve, and in terms of the needs of other users.

Statutory requirements to enable source directed control are based on the authorisation of water use. Granting of water use authorisations must consider equity, sustainability and optimal beneficial use (efficiency).

The NWA furthermore makes provision for the development of Water Management Strategies, which provides the framework for the protection, use, development, conservation, management and control of water resources (DWAF, 1999). Catchment Management Strategies give effect to this national strategy within specified areas, and seek co-operation and agreement on the water resources management from the stakeholders in the area.

5.5 Physical Planning Act

In 1967 the Physical Planning and Utilisation of Resources Act 88 of 1967 (“the Physical Planning Act, 1967”) was enacted to promote co-ordinated environment planning and the utilisation of the Republic’s resources by, inter alia, the placing of certain restrictions on the use of land and the compilation and approval of guide plans. 28

In order to make guide plans binding and to give them legal status, the Physical Planning and Utilisation of Resources Amendment Act 73 of 1975, inserted sections 6A and 6B into the Physical Planning Act, 1967:

· section 6A made provision for the establishment of a guide plan committee to compile a guide plan for a designated area and for the approval thereof; and

· section 6B placed restrictions on the use of land for certain purposes, such as brickworks, without the authority of a permit.

The relevant notice and boundary description of the guide plan area appeared in Government Notice 195 of 3 February 1978. After various consultations a draft Guide Plan was produced and made available for inspection in terms of section 6A(6) of the Physical Planning Act, 1967 on 9 May 1980.

In 1981 the Physical Planning Act, 1967 was again amended by the Environment Planning Amendment Act 51 of 1981 ("the 1981 Act") which introduced various new procedures to be followed in the drafting and adoption of a guide plan. These amendments included a provision (inserted as the new section 6A(17)) that:

"The provisions of the Physical Planning Act, 1967 as they existed before the commencement of the 1981 Act shall continue to apply to -

(a) any guide plan approved before such commencement; and (b) draft guide plans which at such commencement were already made available in terms of [section 6A(6)] provided ...that all amendments of any guide plan shall be made in accordance with the provision of the Physical Planning Act, 1967 as amended by the 1981 Act".

The 1981 Act commenced on 27 March 1981.

The Minister caused his approval of the Guide Plan to be published in terms of section 6A(9) (as it read prior to the amendment effected by the 1981 Act) of the Physical Planning Act, 1967 in Government Notice 1660 on 6 August 1982. Although this was after the commencement of the 1981 Act, the approval was valid in terms of section 6A(17)(b), as the Guide Plan had already been made available for inspection. Indeed, since section 6A(17) was couched in peremptory language ("shall"), there was no other le gal way of approving the Guide Plan. This is also acknowledged in paragraph 1.1 (on page 2) of the Introduction to the Guide Plan (du Plessis; 2001).

Section, 6A was subsequently amended in 1983, 1984 and 1985. However, those amendments did not alter the legal status of the Guide Plan.

On 9 February 1996 (in terms of Government Notice 169) the Deputy Minister of Land Affairs exercised this power and declared in terms of section 37(2)(a)(i) and (ii) of the Physical Planning Act, 1991 that paragraphs 37(1)(c) and (d) of that Act would no longer apply to the Guide Plan and that the Guide Plan would be deemed to be a Regional Structure Plan with effect from that date.

With effect from 25 December 1996 (the date of publication of Premier's Proclamation 57 of 1996 in the Provincial Gazette), the Guide Plan (at that stage formally known as "The Regional Structure Plan for the Vaal River Complex") was "withdrawn as a statutory document" by the Gauteng MEC for Development Planning and Local Government "with the exception of Annexure C conditions". That withdrawal took place in respect of "the part of the regional structure plan for the Vaal River Complex which is located in Gauteng". The MEC acted pursuant to his powers in terms of section 29(3) of the Development Facilitation Act 67 of 1995. The proclamation further provides that "Annexure C will still be used in the evaluation of applications for land use changes and will only be withdrawn when an acceptable substitution becomes available by way of the Land Development Objectives."

The Guide Plan accordingly became a valid Regional Structure Plan in terms of the Physical Planning Act, 1991 by proclamation on 9 February 1996. Whatever its past status might arguably have been, its present validity must accordingly be tested against the provisions of the latter, and not the former Act.

The Physical Planning Act, 1991 makes provision for policy plans to promote the orderly physical development of designated areas:

Section 5 provides that "the objects of a policy plan shall be to promote the orderly physical development of the area to which that policy plan relates to the benefit of all its inhabitants".

(e) section 6(1) provides that “[a] policy plan shall consist of broad guidelines for the future physical development of the area to which that policy plan relates ; and (f) section 6(2) that it "may provide that land shall be used only for a particular purpose”; (g) the long title of the Act envisages the promotion of "orderly physical development of the Republic".

If one analyses Chapter 5, read with Annexure C to the Guide Plan, it is clear that the Guide Plan consists of "broad guidelines for the future physical development of the area" and that it also provides that "land shall be used only for ...particular purpose[s]". The contents of the Guide Plan accordingly falls squarely within the ambit of section 6 of the Physical Planning Act, 1991.

Annexure C clearly deals with development, and is not a land use provision. This view is enforced by the wording of the Gauteng Premier's Proclamation 57 of 25 December 1996, which was, significantly, issued in terms of the Development Facilitation Act 67 of 1995: Paragraph (a) withdraws the Guide Plan (or more, correctly, the Regional Structure Plan) as a statutory document for Gauteng, with the exception of Annexure C. This had the effect of withdrawing all land use provisions for Gauteng, which was only left with the guidelines for development contained in Annexure C. Accordingly, paragraph (b) of the Proclamation provides that Annexure C may still be used in the "evaluation of applications for land use", although it appears that Annexure C will be of fairly limited assistance in such evaluation. The fact that the Proclamation states that Annexure C will 31 only be withdrawn "when an acceptable substitution becomes available by way of the Land Development Objectives", lends force to the view that Annexure C deals primarily with development, and not land use.

Consequently, Rand Water as a body mentioned in Annexure C, tasked with the enforcement of certain land development issues, is legally obliged to regulate the development of land in accordance with the set guidelines of Annexure C.

5.6 Conservation of Agriculture Resources Act (43) of 1983

Section 5 (Regulation 15 and 16) of the Conservation of Agriculture Resources Act, Act 43 of 1983 as amended; provides for the removal of aquatic weeds from any land or water body by the owner or person responsible for the management thereof. Rand Water is therefore obliged to keep the reservoir free from aquatic weeds such as water hyacinth.

5.7 Constitution of the Republic of South Africa Act, No 200 of 1993

This constitution includes two strategic principles, which are not part of the preceding statutory requirements. These are the following : a) Section 29 of the Constitution states : “Every person shall have the right to an environment, which is not detrimental to his or her well-being.” Thus water of a quality that will not be harmful to South African inhabitants has become a basic right. b) Schedule 6 of the Constitution determines that the environment is a provincial competence. This requirement impacts directly on the existing policy, planning, design and implementation management parameters regarding water quality.

5.8 Environmental Conservation Act. Government Notice No 51, GG No 15428 of 21 January 1994

This Government Notice was promulgated under Section 2(1) of the Environment Conservation Act, No 73 of 1989 with the concurrence of all Ministries involved in some way or another with environmental management, the (then) Minister of State Expenditure, all the Provincial Administrators and the Council for the Environment. Policy issues in these statutory requirements of importance to water quality management in the context of the present study, are the following : a) The Preamble to the policy statement repeats the rights of the South African inhabitants contained in paragraph (a) under the Constitution above. It also mentions concepts regarding the State and inhabita nts such as trusteeship of the environment, taking responsibility for impacts on the environment, the maintenance of natural ecosystems, species diversity and environmental survival needs, judicious renewable resource use, sustainable resource planning and usage, and co-operation between the State and private sectors at all levels. b) The Preamble also addresses the matter of an Environmental Management System. This requires each statutory organisation and institution to accept full responsibility and accountability for implementing the policy requirement allocated to them. All organisations and institutions, government, private and other stakeholders, are encouraged to establish formal environmental management systems. (This policy, in contrast to the Cons titution, still accepts that environmental management is primarily a central government responsibility.) c) The Policy statement covers issues such as environmental education, land use, nature conservation, cultural heritage, the urban environment, pollution control, conservation of natural resources, economic measures, research and international co-operation. This document could well serve as a baseline for future discussions about environmental management in general and, more specifically, water quality management. Concepts reflecting the post April 1994 environmental thinking are contained in this policy, such as devolving law enforcement functions down to provincial/regional and local levels of government, integrated pollution control, integrated waste management, education and training (empowerment and capacity building) and sustainable resource use.

5.9 Water Laws Rationalisation and Amendment Act, No 32 of 1994

This Act achieved one objective relevant to this study, namely : a) Water Boards (eg Rand Water) were empowered to provide sanitation services.

5.10 Development Facilitation Act, No 67 of 1995

This new Act has five declared development objectives, mainly directed at RDP projects, namely : a) a common development procedure; b) re-orientatio n of existing spatial patterns; c) interim facilitation of land development planning; d) “fast tracking” through existing development and registration procedures; and e) general frameworks to guide and facilitate.

Concerns about the potential impacts of this Act and the planned regulations have been expressed by other central and provincial government institutions involved with development planning and implementation. The major fear expressed was that this Act will supersede other legal mechanisms (such as the Guide/Structure Plan), which ensure sound spatial planning.

5.11 Reconstruction and Development Programme (RDP)

Within the context of this study, the RDP document and the policy objectives and principles expounded therein are important parameters which should be considered in the design of a management plan for the Vaal River barrage catchment area.

The following relevant issues are put forward in the RDP document :

- equitable access to natural resources; - sustainable use of resources; 34

- participatory planning and decision making; - prevention of pollution; - integrated pollution control; - a safe and healthy environment; - integrated waste management; - rationalisation of legislation; - effective regulation; and - Commission on the Environment.

The main points in the Chapter of the RDP document covering water and sanitation can be summarised as follows :

- scarcity of water and uneven distribution; - the right of access to clean water : “water security for all”; - water in the context of settlement planning; - goals of water management : * meeting every person’s health and functional requirements, * raising agricultural output, * supporting economic development; - dangers of overuse and inappropriate disposal; - emphasis on the health of inhabitants : clean water and appropriate sanitation; - accessibility of water and sanitation; - emphasis on community participation in decision-making; - particular focus on rural areas and village water committees; - affordable and realistic tariffs; - restructuring of the Department of Water Affairs and Forestry; and - establishment of “catchment-based institutions” on the second tier.

The above focus points should be seen in the context of the total RDP document and should be integrated with all the other social, political, legal, economic cultural and technological issues.

From the above it is clear that sufficient legislation exists for the protection of the VRBR, specifically aimed at ensuring a supply of water of a quality that can be efficiently treated and put into the potable supply.

The activities specifically aimed at protecting the water quality are described in Chapter Six. 36

6. WATER QUALITY MANAGEMENT IN THE VAAL RIVER BARRAGE RESERVOIR .

6.1 Background Information.

The Vaal River Barrage reservoir is not only an important source of raw water for industrial, agricultural and domestic use within Gauteng and the lower Vaal River, it is also one of the prime recreational sites of Gauteng.

It is therefore essential that this valuable water body be managed in such a manner that it remains suitable for the said purposes. Studying the current water quality information of the Vaal River Barrage reservoir and its catchment, it is clear that there is reason for concern regarding the water quality of this impoundment. Degradation of water quality relates to the following :

· Eutrophication, aesthetic and health related problems caused by sewage discharges. · Salinity and toxicity problems caused by industrial and mining pollution. · Microbiological pollution from formal and informal urban development.

To establish the suitability of this water body for water contact sports Rand Water maintains a regular monitoring programme along the course of the river; including the Loch Vaal. Of particular concern is the high bacteriological and algal counts which often exceed national limits for recreational use (DWAF, 1993) at certain sampling sites. The monetary value of fixed properties riparian to the reservoir and money spent by people for recreational purposes amounts to a formidable amount. The deterioration in water quality of the Barrage reservoir can therefore affect personal preferences of people with regard to the aesthetic value of the reservoir, which may lead to a reduction in property values and recreational usage of the reservoir with associated financial losses to the local economy.

6.2 Monitoring and Analyses.

An intensive monitoring programme, covering the river and its tributaries, is maintained. The main aims of the monitoring programme are:

· To protect the resource from deterioration, · To predict changes in water quality that may afffect Rand Water’s ability to produce high quality potable water · To produce timeous water quality audit (status) reports relevant to specific uses, · For management decision making purposes.

Fortnightly samples are taken at about 10km intervals along the length of the Barrage, with additional samples in the Loch. These samples are analysed for chemical and biological constituents, and the results are made available to the public through weekly leaflets and a 24 hour information hotline, as well as the Internet.

An example of the routine water quality report for recreational purposes is enclosed as Appendix 2.

6.2.1 Selection of Sampling Sites

The most important objectives of the Vaal Barrage Reservoir monitoring programme are to:

· Provide a safe supply of raw water for potable purposes · Ensure appropriate resource planning and management by sharing responsibilities with all interested and affected parties and through active participation in all catchment forums. · Protect and improve the aquatic environment for all user requirements in a sustainable manner · Ensure a long term viable economic future for the respective watershed dependants · Determine current and predict future raw water quality that may render existing treatment facilities inadequate or require additional processes · Ensure the safety of public using the water for recreational purposes 38

· Prevent degradation of natural resources · Restore degraded resources · Contribute to all educational initiatives aimed at promoting the wise usage of water · Inform public of water quality conditions that might result in human health problems · Manage the Vaal River Barrage in a responsible manner to ensure that the needs of the riparian owne rs are met.

The management of the Barrage Reservoir is complex and involves many different stakeholders. Rand Water, as owner and custodian of the Barrage Reservoir, treats the water in the Barrage as part of its works and consequently the catchment mana gement services attempt to ensure that the quality of the Barrage is acceptable for the user requirements. The Barrage reservoir is used for a variety of purposes such as potable raw water supply (steel, petro-chemical and power generation) and limited aquaculture. The natural aquatic ecosystem is part of the base in the Barrage which are also used as a subsistence protein source.

Historical monitoring programme

The historical monitoring programme of Rand Water on the Barrage Reservoir dates back to 1984. Samples were collected every two weeks at the following six sampling points:

0 km (Vaal Barrage Wall); 10 km (downstream of Leeuspruit draining Sasolburg); 37 km (downstream of Vereeniging), 45 km (upstream of Suikerboschrant River), and 49 km (downstream of Lethabo weir).

At each sample point three samples were collected: · Surface · Middle (± 2-3m) · Bottom (± 4-6m)

In 1999, the reservoir sampling programme was evaluated to ensure optimisation application of resources, as well as to ensure that the monitoring produces the optimum level of information required.

The water quality was analysed between sample depths and sample sites to determine if there are significant difference between the means of these samples. The data from 1984 to 1998 were used. The metals and sulphate values from February 1998 to January 1999 were analysed to determine the difference between the sites (Heath, et al, 1999).

The study concluded that there were little or no statistical differences in the water quality at different depths. The investigation resulted in the following changes to the monitoring programme for the Barrage reservoir, implemented since 1999:

· Two-weekly composite samples are collected at sites 0 km, 10 km, 24 km, 37 km, 45 km and 49 km. · No more depth samples to be collected.

For the Loch Vaal, the number of sampling sites were reduced from 10 (LV1 – LV10) to only three, being · LV 6 – representing the inflow, · LV 8 – in the middle of the Loch, and · LV 10 - representing the outflow (Heath, et al, 1999).

6.2.2 Selection of Water Quality variables.

Since 1984, the water was analysed for the following constituents;

Table 1: Original constituents analysed for in the monitoring programme.

In situ Laboratory

Dissolved oxygen (mg/l) pH – compared to field measurements Electrical conductivity (mS/m) Major cations and anions (mg/l) PH Nutrients-nitrate, nitrite, ammonia, total and ortho-phosphate (mg/l) Temperature ( 0C) All major metals (mg/l) Turbidity COD (mg/l) Secchi (m) DOC (mg/l)

TOC (mg/l) Alkalinity (mg/l) Hardness (mg/l) Chlorophyll-a (mg/l) Total coliforms (counts/100 ml) Algal cell counts

The investigation in 1999 assessed the necessity of analysing all of the above and resulted in the selection of variables for the Barrage reservoir indicated in Table 2, and for the Loch Vaal in Table 3 (Heath, et. al., 1999). 41

Table 2: Variables selected for the Barrage reservoir monitoring programme.

Sites Frequency Physical Chemical Biological Comments 0km, 10 km, Monthly Secchi Alkalinity, amonia, calcium, Algal Review every two 24 km, 37 km, integrated chloride, COD, composition, years 45 km, 49 km sample Conductivity, fluoride, chlorophyll-a DOC, hardness, iron, magnesium, nitrate, orthophopshate, pH, phosphate, potassium, silica, sodium, sulphur, sulphates, SS, TKN, T- phosphates, Six monthly Arsenic, boron, cadmium, Review annually chromium, cobalt, copper, gold, lead, manganese, molybdenum, nickel, vanadium, zinc

Table 3: Variables selected for the Loch Vaal monitoring programme.

Sites Frequency Physical Chemical Biological Comments LV 6 Integrated Secchi Alkalinity, amonia, calcium, Algal Review every two LV 8 surface sample, chloride, COD, composition, years LV 10 two-weekly Conductivity, fluoride, chlorophyll-a DOC, hardness, iron, magnesium, nitrate, orthophopshate, pH, phosphate, potassium, silica, sodium, sulphur, sulphates, SS, TKN, T- phosphates, Six monthly Arsenic, boron, cadmium, Review annually chromium, cobalt, copper, gold, lead, manganese, molybdenum, nickel, vanadium, zinc

6.3 Receiving Water Quality Objectives.

The most sensitive water use would usually determine the desirable limit for each key water quality variable. In the Barrage reservoir, nutrient levels have to be kept to a lower level than in its upstream tributaries. This situation arises due to the slow moving flow conditions in the Barrage being more conducive to the propagation of nuisance algae than is the case for the faster flowing tributaries (DWAF &RW, 1996). The prevalence of full contact recreation on the Barrage reservoir could also lead to more stringent guidelines for bacteriological contaminants than for its upstream tributaries.

The more exacting requirements of downstream river reaches could well result in the adoption of higher water quality requirements than are needed to satisfy only the local users. Cases in point are the Klip River and the Rietspruit, where reductions in bacteriological, nutrient and salinity levels (especially phosphate) may be required to meet the requirements for the Vaal River Barrage and users further down the Vaal River.

An important consideration is that the setting of limits for the tributaries of the Barrage reservoir to meet water quality limits for the Barrage (and downstream reaches of the Vaal River) is complicated by the fact that the concentrations arising in this water body are modified by the dilution effect of water releases from the Vaal Dam. These releases are in turn a function of the downstream water demands, local tributary inflows and the system operating rules employed.

In the case of meeting water quality requirements for potable water supply, such as Rand Water’s aim of keeping the supply water electrical conductivity (EC) below 45 mS/m (also known as the “300 mg/l TDS Blending Option”), this can be met in a number of ways. For example, the blending scheme presently in operation (the “600 mg/l TDS Blending Option”, makes it possible to meet this limit in supply irrespective of the water quality in the Barrage reservoir. The acceptable EC limit for the tributaries entering the Vaal River Barrage therefore depends on how the Vaal Dam and the Vaal River Barrage systems are operated.

It follows from the above considerations that the setting of optimum water quality objectives for the points of confluence of the Klip River, Suikerboschrant River, Riet Spruit, Taaibos Spruit and Leeu Spruit to meet the requirements for the Barrage reservoir requires an iterative approach, whereby different combinations of tributary water quality targets and system operating rules are tried out and successively refined. One of the constraints on this optimisation process will be the need to meet the requirements of downstream users.

6.3.1 The Role of Water Quality Objectives.

The development of water quality objectives is a crucial step in the development of a water quality management plan (Van Veelen & Venter, 1996). These objectives should be develo ped as part of a co-operative consultative process in order to ensure that they are realistic and what the community as a whole desire.

While the ideal river water quality requirements stand as an ultimate ideal, it is accepted that practical realities, such as socio-economic constraints, may prevent their attainment, at least in the short term. Hence it is necessary to think in terms of ultimate goals, with a tiered system of quality objectives leading to their eventual attainment. Following the derivation of ideal water quality requirements, and once the hydrological and pollutant inputs from the tributaries of the Barrage reservoir have been quantified, it may become apparent that the meeting of the ideal water quality requirements for certain river reaches would be prohibitively expensive, or result in an unacceptable deterioration in the assurance of supply. In such instances the immediate water quality objectives may need to be revised (DWAF & RW, 1996).

For example, the reduction of biological contamination in the Klip River to a level where it is safe for domestic use is unlikely to be practically realisable. In instances it may be found that mitigation at the point of abstraction is more cost effective than curtailment at source. For example, the desalination of a relatively small volume of water required for boiler feed for a power station or factory to a very high standard could prove to be much cheaper than, for example, desalinating much larger volumes of water discharged by a number of upstream gold mines.

The early short term water quality objectives set for the different river reaches will most likely depend for their viability on interim ameliorative measures aimed at minimising the impact of pollution sources, such as the TDS blending options. However, increasing emphasis will need to be placed on catchment management strategies aimed at curbing pollution at source to ensure sustainable fitness for use.

Since the system is dynamic, care will have to be taken to ensure that new developments do not render previously agreed objectives redundant or inappropriate. Hence it will be necessary to continually monitor developments and revise water quality objectives and management strategies accordingly.

6.3.2 Identification of Key Water Quality Variables

In the Barrage catchment, an enormous number of different organic and inorganic constituents have the potential to pose water quality problems. It is therefore essential to obtain some focus regarding which variables are the most significant in terms of water quality management. For example, Rand Water regularly analyses for about 80 water quality variables, all of which have been assigned target guideline limits. Many of these are not critical with respect to the production of potable water since the undesirable components are removed by Rand Water’s purification process, or because the concentrations present in the water are well within acceptable limits. However, certain variables are already problematic. Some of these problematic water quality variables, such as chlorophyll and organic load, are treated by conventional means, but at elevated costs; whilst others, such as salts, are relatively intractable and can be removed only by using advanced and expensive technology (DWAF & RW, 1996).

Water quality issues of particular concern that have been identified include : i. Salinity

Salinity is difficult and costly to reduce at source. At present Rand Water and DWAF manages this problem by blending. However, the users downstream of the Vaal River Barrage such as Sedibeng 46

(Goudveld) Water and agricultural users do not have this management option and are experiencing problems with salinity (eg. salinisation in the Vaalharts Irrigation Scheme). Furthermore, the blending option will become more difficult to apply as high quality raw water becomes scarcer and more expensive, and as salinity levels rise in the Middle and Lower Vaal River systems.

The mining industry (eg Grootvlei Mine, ERPM and Durban Roodepoort Deep) are currently allowed to discharge highly saline effluent into the Vaal River System. The cost to downstream users and the potential benefits of costly treatment at source need to be quantified.

The water quality variables of most concern with regard to salinity include :

- Total Dissolved Salts (TDS), an indirect measure of which is provided by electrical conductivity (EC), which is much easier to monitor. Elevated TDS and EC levels result in reduced crop yields for irrigation farmers, high costs for desalinating or softening water used by industries for steam raising, cooling, refrigeration or process water and increased costs for domestic users due to the scaling of geyser and kettle elements, increased soap consumption, etc. TDS can be viewed primarily as an economic problem, although at higher levels salinity can lead to kidney problems.

- Sulphate , which increases the corrosion potential of water, as well as having laxative effects at elevated concentrations.

- Chloride , which increases the corrosion potential of water and adversely affects crop production.

- Sodium, which can affect cardiac patients, reduce crop yield and lead to sodicity problems that lead to the reduction of soil drainage and consequent damage of agricultural lands. The Sodium Adsorption Ratio (SAR), which is based on the balance between sodium and the other major cations, calcium and magnesium, is a measure of the sodicity hazard posed by irrigation water.

- Hardness, which results in scale formation, especially in hot water systems.

- Bicarbonate, which poses problems for certain irrigated crops. ii. Eutrophication

- Algal blooms are the most severe symptom of eutrophication problems in the reservoir with regard to the production of potable water, since they tend to block filters, can result in toxicity, taste and odour problems and indirectly result in excessive carcinogenic trihalomethane (THM) formation when pre-chlorination is used to combat algal problems. They can also reduce the effectiveness of disinfection by providing a refuge for bacteria and provide a source of carbon that can support bacterial growth. All of these adverse effects have economic implications. Excessive algal growth also adversely affects recreation and the natural environment.

- Excessive plant nutrient concentrations, in particular phosphate, have been identified as the most important causes of eutrophication problems in the Barrage reservoir. High nutrient levels in this water body can also contribute to eutrophication problems experienced further downstream in the Middle Vaal River. iii. Pathogens

Bacteriological pollution, associated mainly with raw sewage overflows and contamination from squatter settlements adjacent to streams, has reached levels where it poses a threat to the domestic and recreational water use in a number of tributary river reaches, as well as in the Barrage reservoir. Of particular concern are the Klip River and Rietspruit (west) catchments.

A host of bacteriological, viral and parasitic variables are of concern. A commonly used indicator of potential health related effects is provided by the Escherichioa coli bacteria. The selection of other indicator variables may eventually be required to ensure that a wider range of potential problems is covered. 48

iv. Other problem variables

Other problem variables that have been identified include fluoride (Taaibosspruit catchment and Sasol 1 effluent), various metals (associated with industrial and mining activities), pH (acidity primarily associated with headwater streams near to mining sources), radionuclides (mining effluent) and ammonia (associated with raw sewage spillage, certain industrial wastes and mining activities), oils and soaps (referred to as methylene blue active substances, MBAS) and other organic matter pollution (associated with various industrial activities and raw sewage) and turbidity and associated sedimentation (associated with mining, construction and urban activities). The potential also exists for contamination from toxic waste sites, and pesticides and herbicides associated with agricultural activities.

6.3.3 Rand Water’s requirements for purification purposes

Section 9(1) and 73(1)(j) of the Water Services Act, Act No 108 of 1997 requires that certain water quality norms in respect of potable water should be met. The list of water quality variables included in the SABS 241 of 1999 which is used for this purpose, far exceeded the existing list of in -stream water quality variables for the Barrage reservoir (Rand Water, 2001b).

As some of these variables are not removed by conventional water treatment processes it is imperative that water services providers are aware of the concentration levels of these variables or changes in concentration levels of these variables in the source waters. The latter, in concert with the necessity to protect this valuable recreational site and to secure the water quality for industrial and agricultural uses, has necessitated the revision of the in-stream water quality guidelines for the Vaal River Barrage reservoir. Rand Water’s original raw water quality requirements, based on the capacity of the purification works to remove the selected variables, are listed in Appendix 1.

The set of water quality guidelines developed by the Vaal Barrage Catchment Executive Committee (CEC) is aimed at providing a set of values for the Vaal River Barrage Reservoir by means of which 49

the water quality in the reservoir can be managed. The guidelines should be compiled in such a manner that it affords maximum protection to the water for all its intended users and for the measurement of progressive improvement through a system of tiers starting off at a level of unacceptable water quality and ending at a level considered to be ideal for this specific sub- catchment of the Upper Vaal Water Management Area (Rand Water, 2001b).

The raw water quality requirements for Rand Water’s operational purposes are indicated in Appendix 1.

6.3.4 Department of Water Affairs & Forestry’s RWQO’s

The set of in stream water quality objectives derived for the Barrage reservoir in January 1998 (Table 4) is limited in extent and in need of revision as it does not meet the existing requirements of the major users within the Upper Vaal Water Management Area. Water users within this area include the production of drinking water, industry, mining, agriculture, water-based recreation and the environment (Rand Water, 2001b).

Table 4: Receiving Water Quality Objectives - DWAF

Constituent Unit Target Constituent Unit Target Conductivity mS/m 30 Phosphate mg/l 0.4 Sodium mg/l 40 Boron mg/l 0.1 Sulphate mg/l 80 Fluoride mg/l 1 Chloride mg/l 50 Manganese mg/l 0.6 Nitrate mg/l 6 E. coli Per 100ml 126

6.3.5 Determination of Ideal Water Quality Requirements

The setting of river water quality objectives holds the potential for conflict between downstream water users and upstream polluters. This requires a transparent negotiating process with sensitive 50 handling of conflict resolution to ensure that all stakeholders buy into the process and co-operate fully to achieve the desired results. It may not always be practical to meet the ultimate water quality objectives in one step. Instead a phased approach may be needed, with a programme of achievable interim objectives being set, leading to the eventual attainment of the long term quality goals.

The water quality guideline limits set out in the South African Water Quality Guidelines (DWAF, 1996) serve as the initial departure point for the setting of target water quality guidelines for each type of identified user. The target guidelines derived from this source are aimed at ensuring negligible adverse effect on users. As such they represent ideal conditions. It follows that site specific investigations are required to determine the actual water quality requirements of some categories of user. In particular such investigations are likely to be required with respect to (i) recreation use and (ii) the natural environment. Furthermore, for all water uses it is necessary to consider both actual and potential future water use (DWAF & RW, 1996).

Another factor to take into account is the appropriateness of the water use. For example, if the climatic and soil conditions are unsuitable for producing a crop such as tobacco, then it would be illogical to attempt to manage the catchment to keep chloride levels below the 25 mg/l required for this crop. Similarly, it is not realistic to manage a natural river to obtain the zero faecal coliform target required for domestic water (DWAF & RW, 1996).

The water quality objectives for the Barrage Reservoir were determined by means of a workshop held under the auspices of the Vaal Barrage Catchment Executive Committee (VBCEC) in August 2001. The methodology is described hereunder.

Guiding Principles

Throughout the catchment of the Barrage reservoir, communities use the water from the river and its tributaries for domestic purposes. The guiding principle in setting in-stream water quality objectives, was that water taken from any river for domestic purposes should pose no threat to human health after boiling.

This set of in-stream water qua lity guidelines were set taking cognisance of the following: § Activities within the drainage basin of the catchment § The identified users within the catchment § The analytical detection limits of the respective water quality variables § Existing water quality in both the Vaal Dam and the outlet of the Vaal River Barrage reservoir § The setting of guideline values in such a manner that it will enable managers to measure progression in water quality status from the undesired status to the desired status.

Number of tiers and the naming thereof. a) Numbering of tiers

The number of tiers used by the national and international water industry for the measurement and evaluation of either potable or raw water resources against specific water quality norms varies from two to five.

Most of the river forums within the Upper Vaal Water Management Area employ a four-tier structure and this is also the existing situation regarding the Barrage reservoir. During the workshop it was decided to retain this status and that a four tiered system of criteria be developed for the Vaal River Barrage Reservoir. b) Naming of tiers

In naming the tiers it was considered important that the names enable users thereof to identify themselves with the goals of the specific tiers. The most commonly used nomenclature for this purpose comprises the following: Tier 1: Ideal Tier 2: Acceptable Tier 3: Tolerable Tier 4: Unacceptable

During the workshop much discussion resulted around this topic and it was the opinion that whilst it was possible to logically set levels for tiers 1 and 4, this was less easy to do so for levels 2 and 3. It was stated that it would be rather difficult to substantiate concepts such as acceptable and tolerable.

Because the intended set of guidelines was considered a measurement tool for the effective management of water quality in the catchment it was decided to replace the terms acceptable and tolerable with management and interim target for respectively tiers two and three. Ideal was replaced with Reference value.

Tier one (Reference value)

Tier one describes the baseline for the catchment and therefore act as reference to the catchment. The intention of this tier is to describe the virgin (ideal) status of the catchment, taking cognisance of all the natural impactors on the catchment. For this purpose the quality of the Vaal Dam water prior to the implementation of the major inter-basin transfer schemes was used for this purpose where information was available. Detection limits for the respective water quality variables were also taken into account during the setting of the guideline values for tiers one and two.

Tier four (Maximum value)

Concentrations of water quality variables above the limits set for tier three were considered unacceptable and were therefore la belled as the maximum concentration levels for the respective water quality variables. Setting of guideline values for tier four were primarily governed by the upper limit of Class 1 water as defined in the SABS 241 (1999) guidelines for drinking water.

The rationale behind this decision was based on the following two aspects: · Given the existing situation in our country, a large sector of our population do not have piped water and, will for the foreseeable future be reliant on water taken directly from streams and rivers for their domestic requirements. Meeting these requirements would safeguard these users provided that some rudimentary treatment such as screening/filtering and boiling of the water is done. 53

· The ability of existing conventional water treatment works to remove the respective water quality variables to meet existing potable water quality standards.

The above, in concert with the water quality guidelines set for recreational, agricultural, industrial and environmental use as indicated in the Department of Water Affairs and Forestry’s field guides (Guides 1-8, 1996), were the main drivers against which the respective variables were judged.

Tier two (Management target)

Tier two was the most difficult to set in that it really embodied the catchment target value which implies the value that can optimally be achieved considering all the complicating aspects of the catchment. Much time was spent on this level and it was guided to some extent by the prevailing water quality conditions at the exit point of water from the Vaal River Barrage Reservoir and the information gathered in respect of tier 4.

Tier three (Interim target)

Tier three was considered a short-term management tool and an interim goal between the maximum value and the management target level. Its primary aim is to identify progression from the status quo

(existing concentrations in the catchment) or the unacceptable status to the management target level.

Setting of Objectives

Each individual variable was introduced taking cognisance of: · Users · Present concentration levels at the exit point from the Barrage reservoir · Catchment reference values as outlined under point 3 (Vaal Dam pre 1998) · Maximum level defined for class 1 drinking (SABS 241 of 1999) · Detection limits for respective water quality variables.

The revised set of objectives set by VBCEC is illustrated in Table 5. 54

Table 5: Receiving Water Quality Objectives - VBCEC

VAAL BARRAGE WATER QUALITY GUIDELINES ( Version 1) Catchment Management Parameter Units of measure Interim target Unacceptable background target Chemical and Physical properties Conductivity (mS / m) <18 30 70 >70 pH (pH units) 7.0 - 8.4 6.5 - 8.5 6.0 - 9.0 <6.0 - >9.0 Dissolved oxygen (mg / l) Organic Determinants Phenols (mg / l) 0.01 0.1 >0.1 Atrazine (µg / l) <5 <10 10 - 20 >20 COD (mg / l) <10 20 30 >30 Trace elements (Dissolved) Antimony (µg / l as Sb) NV 5 10 >10 Arsenic (µg / l as As) NV 10 20 >20 Cadmium (µg / l as Cd) <30 3 5 >5 Chromium (Total) (µg / l as Cr) <30 30 50 >50 Cobalt (µg / l as Co) <50 50 100 >100 Cyanide (Free) (µg / l as CN) NV 5 10 >10 Lead (µg / l as Pb) <10 30 50 >50 Mercury (µg / l as Hg) NV 1 2 >2 Nickel (µg / l as Ni) <50 50 100 >100 Selenium (µg / l as Se) <10 20 30 >30 Vanadium (µg / l as V) <50 100 200 >200 Zinc (µg / l as Zn) <50 100 200 >200 Macro Elements & Miscellaneous Determinants (Dissolved) Aluminium (mg / l as Al) NV 0.3 0.5 >0.5 Ammonia (mg / l as N) <0.5 0.5 1 >1 Calcium (mg / l as Ca) 15 70 150 >150 Chloride (mg / l as Cl) 5 50 75 >75 Copper (mg / l as Cu) <0.05 1 2 >2 Fluoride (mg / l as F) 0.19 0.7 1 >1 Iron (mg / l as Fe) NV 0.5 1 >1 Magnesium (mg / l as Mg) 8 30 70 >70 56 VAAL BARRAGE WATER QUALITY GUIDELINES ( Version 1) Catchment Management Parameter Units of measure Interim target Unacceptable background target Macro Elements & Miscellaneous Determinants (Dissolved) Manganese (mg / l as Mn) 0.15 0.15 0.2 >0.2 Nitrate (mg / l as N) 0.5 3 6 >6 Potassium (mg / l as K ) 5 15 25 >25 Sodium (mg / l as Na) 15 50 100 >100 Sulphate (mg / l as SO4) 20 100 200 >200

Phosphate (Ortho) (mg / l as P) NV 0.03 0.05 >0.05 Boron (mg / l as B) NV 0.3 0.5 >0.5 Protozoa Giardia (org / 10 litre) 0 0 0 1 Cryptosporidium (org / 10 litre) 0 0 0 1 Bacteria Faecal Coliforms (cfu per 100 ml) 126 1000 >1000 Cyano Bacteria (Cell coints/ 100Ml) <10000 20000 >20000 Biological indicators and toxicity testing Chlorohyll a (µg / l ) 5 15 30 >30 Daphnia (Acute toxicity) (% survival) 100 90 80 <80

NV = Not available.

Chapter Seven describes the current water quality status of the Barrage reservoir, and provides a realistic test for the appropriateness of the above guidelines.

7. WATER QUALITY STATUS OF THE VAAL RIVER BARRAGE RESERVOIR.

7.1 Salinity.

Estimates from the many studies that have been carried out on various aspects of pollutio n of the Vaal River indicate that the contribution from non-point source discharges is about 40 % of the total dissolved salts (TDS) load entering the system. Mine dewatering produces another 25 % of the total load and industries and sewage works contribute about 35 % of the total load (SRK, 1993).

A total of 76 310 m³/d of industrial effluent is discharged to municipal sewage works and the salt load is increased by some 103 t TDS/d (SRK, 1993).

The Vaal River Barrage catchment receives 66 % of the efflue nt volume and 78 % of the TDS load from the above mentioned industries. The components of the combined industrial salt load are illustrated in Table 6.

Table 6: Components of the combined industrial salt load.

Component % of load Load t/d Sodium and Potassium 18 37 Calcium and Magnesium 14 30 Total Alkalinity (as CaCO³) 15 31 Sulphate 30 62 Chloride 20 42 Others 3 6 TOTAL 100 208

The total industrial water intake for the Barrage catchment is 302 Ml/d and the total industrial effluent volume is 140 Ml/d, indicating a return flow of water by industry to the Vaal River of 46 %.

The gold mining industry in the catchment area is extensive, with 45 mines being active. Total discharge to the Vaal River is approximately 135 Ml/d containing about 348 t TDS/d. Water intake to the mines is about 1 000 Ml/d of which about 400 Ml/d comes from underground workings (SRK, 1993). The components of the mining salt load in the Middle Vaal on a mass basis are given in Table 7.

Table 7: Components of the mining salt load in the Middle Vaal.

Component % of load Load t/d Sodium and Potassium 17 58 Calcium and Magnesium 16 55 Total Alkalinity (as CaCO³) 19 66 Sulphate 27 95 Chloride 20 69 Others 1 5 TOTAL 100 348

In 1993 the total discharge of effluent from sewage works to the Vaal River Barrage was 770 Ml/d containing some 402 t TDS/d. The average TDS concentration for sewage works in the Vaal River Barrage is 460 mg/l (SRK, 1993). The effluent volume has grown to 900 Ml/day by 2001 (Van Der Schyff, 2001. Pers. com).

Analysis of the available information indicates that, for the Vaal River Barrage, domestic sources account for 75 % of the effluent volume and 33 % of the salt load. For industry, power generation and mining combined, the percentages are 25 % of the volume and 67 % of the salt load for the Vaal River Barrage (SRK, 1993). 59

Based on the limited historical data, the ratio of contribution from point sources compared to non- point sources is assumed to be 50 % point sources, 50 % non-point sources fo r times of average rainfall; 60 % point sources, 40 % non-point sources for below average rainfall; 40 % point sources and 60 % non-point sources for above average rainfall. The percentages of the volume and salt load contributions were considered to be the same for each of the three conditions of rainfall (SRK, 1993).

Figure 7 illustrates the Electrical Conductivity (1984 to 1998) in the Barrage reservoir in a downstream direction. Note the impact of the Klip and Suikerboschrant rivers at km37.

Conductivity 80

20 Conductivity(mS/m) 0

V2 V17 top49 top45 top37 top24 top10 top0

Figure 7: Electrical Conductivity changes from Lethabo weir to the Barrage (Box & Whisker plots).

Solutions:

1. Initially salinity management of the Barrage reservoir was achieved by retaining the better quality water in the upper Vaal catchment behind the Lethabo weir. A 300mg/l TDS (behind Lethabo weir) blending option was then introduced for Rand Water. The disadvantage of this strategy was 60

that users in the middle Vaal River would not benefit from the better quality water in the upper catchment (Quibell, 1991).

After modelling the salt dynamics of the river, a 600 mg/l in situ Vaal Barrage blending option was proposed. Rand water would then make up the balance by direct abstraction from the Vaal Dam. The quality of potable water supplied does not differ signific antly from that supplied with the 300mg/l option. However, the strategy has the advantage that a better quality water would be supplied to the middle Vaal River (Quibell, 1991).

Blending is an attractive option as it is an effective means of ameliorating the effects of both point and diffuse source pollution. It is considered to be cost effective and is already in operation. Blending is not a long term solution on its own, but at present and for the foreseeable future, it represents a pragmatic means of countering increasing salinity levels in the Vaal River Barrage system. The introduction of Lesotho Highlands Scheme water with very low salinity to the Vaal Dam should continue to make blending the most attractive option of control of salinity in the Vaal River system (SRK, 1993).

2. Centralised treatment is attractive from the point of view of benefits of scale in controlling treatment costs. The viability of large scale desalination of outfalls from sewage works which are already centralised treatment works is worth researching (SRK, 1993).

3. The main reason in -house pollution management has not been implemented on a large scale is cost, although changes in the cost of pollution could be brought about by financial disincentives. The negative implications are that it results in a volume of highly saline effluent, the handling and disposal of which remain problematic (SRK, 1993).

4. Transferring effluent to another catchment although already practised to a limited extent is considered only as a last resort. The operation is likely to be costly and is considered the least attractive of options because it merely transfers a problem at considerable cost from one catchment to an adjacent one. Control of diffuse source pollution also warrants more attention in future (SRK, 1993). 61

7.2 Eutrophication

Eutrophication is the enrichment of water systems with plant nutrients. As nutrient levels increase, the number of algal and other aquatic macrophytes increases up to such a level where the ecological balance between the producers (algae) and the consumers is disturbed. This results in an overproduction of algae. Some of the problems experienced are;

· Increased costs of water purification for potable purposes (clogging of filters). · The production of taste and odours by blue -green algae in water for potable purposes. · Aesthetic problems associated with massive growths of algae and aquatic plants. · Interference with recreational uses of water bodies (clogging of propellers and fishing tackle). · The cause of skin irritations on swimmers and diarrhoea by blue-green algae. · The production of algal toxins which can result in livestock losses and may possible have sublethal effects on humans. · The production of ecological changes in lakes with resultant effects on lake biota and chemistry (Steynberg, 1983).

The water in the Barrage at times may contain as much as 85 % of highly mineralised and nutrient rich water originating from the Klip and Suikerboschrant Rivers. Dilution of the tributary water by Vaal Dam water greatly reduces the impact of these rivers on the water quality in the Barrage. Despite this dilution, one of the most pressing problems facing Rand Water is an excessive algal growth in the Barrage reservoir as a result of eutrophication (Viljoen, 1984).

Excessive macrophyte and algal growth diminishes the value of a water body for recreational purposes as fishing lines are snagged, boating is hampered and the water is unpleasant to swim in. Green coloured water with masses of foul-smelling decaying algae floating on the surface is also aesthetically unacceptable to the environment, recreation and riparian owners. The principle effect of eutrophication on fish is one of dissolved oxygen depletion that may result in fish mortality. The long term effect of eutrophication will be one of changed species composition, a result largely of the changed dissolved oxygen status. Increased food supply in the form of more detritus, which tend to 62 lead to a smaller zooplankton and a less diverse worm/midge dominated bottom fauna, would tend to favour detritus/bottom feeding fish such as mud fish and carp. These latter species already dominate in the Barrage. Thus an increase in undesirable fish and a diminishing of desirable species has already adversely affected angling in the Barrage (Viljoen,1984).

The occurrence of algal blooms in the Vaal Barrage became more frequent and severe in the late 1970s and early 1980s. This has required increased prechlorination at the purification works, first started in 1973, in an attempt to control algal growth. Further control measures investigated by Rand Water include the use of activated carbon, ozone, flotation and micro screening (Viljoen, 1984).

In 1973, 100 percent of all chlorophyll determinations at Rand Water’s No. 1 intake showed results of less than 15µg/l. In 1982, only 66% of all analyses indicated a chlorophyll value of below 35µg/l (Van der Merwe, 1984). The average chlorophyll-a concentration in the Vaal River Barrage Reservoir during the October 2001 was 48 mg/l. The highest concentration (114 mg/l) was recorded at the Barrage (0kmT). An average chlorophyll-a concentration of 128 mg/l has been recorded in the Loch Vaal for the same period, with the highest concentration recorded at LV10 (209 mg/l) (Van Baalen & Maritz, 2001).

It is, however, nutrient and in particular phosphorus control which is most favoured in the prevention of eutrophication since this aims to limit the cause of the problem. Because the origin of point sources are known and appropriate technology for phosphorus reduction is available, priority is usually given to point sources as it is generally the most cost effective approach (Viljoen, 1984).

As a result of the difficulties in controlling diffuse sources of phosphorus, it is believed that natural wetlands should not be used as a means of controlling point sources of the nutrient (Viljoen 1984). Viljoen (1984) also predicted that the implementation of the 1mg/l phosphate standard will markedly affect the phosphate input into the Barrage. Predictions indicated that if all the wastewater treatment plants achieved the new standard, phosphate loads entering the Barrage in the year 2000 would be smaller than 1984 loads. If the standard is not implemented, it was predicted that the phosphate load entering the Barrage will increase by 250%, a situation that could not be tolerated. The 63 removal of phosphate through the Suikerboschrant River is notably greater than that removed through the Klip River. The two most important reasons for this are that the percentage sewage effluent discharged into the Suikerboschrant and Klip Rivers, expressed as a percentage of the total flow is 15 % and 50 % respectively; and that the surface area of wetlands in the Suikerboschrant River is much larger than that of the Klip River, rendering the load to surface area of the Suikerboschrant River more favourable for nutrient removal. This phenomenon is illustrated in Figure 8.

Steynberg (1986) analysed the data collected over 12 years (1974-1986) and found evidence that there was a change in the physical, chemical and biological quality of the water. The most noticeable change in the abiotic factors occurred in conductivity, TDS and dissolved ortho-phosphate phosphorus. Over the 12 year period, the ratio of Klip River water to Vaal Dam water became larger whilst the retention time increased. The increase in conductivity and retention time resulted in lower turbidities. Over the above mentioned period, the Vaal River Barrage changed from a water body with predominant river (riverine or lotic ) characteristics to a water body with predominant impoundment (lacustine or lentic) characteristics. These changes resulted in higher algal concentrations (Steynberg, 1986).

Ideally, potable water should not contain any algae. Rand Water, however, uses a chlorophyll standard of 1mg/l for potable water. A chlorophyll value greater than 30mg/l is regarded as the critical raw water chlorophyll concentration as it results in a 50 % or higher probability of the purified water chlorophyll concentration exceeding the 1 mg/l standard. If it is accepted that the frequency of the critical raw water chlorophyll value of 30 mg/l is to be limited to 25 % of the year, then it is necessary that the annual average concentration should not exceed 20 mg/l which, in turn, limits in-situ ortho -phosphate concentration to a maximum of 440 mg/l (Steynberg, 1986).

Figures 8 and 9 illustrate the changes in phosphate and nitrate in the Barrage reservoir (1984-1998) in a downstream direction. In both instances the contributions from the Klip and Suikerboschrant rivers at 37 km can clearly be seen.

Total Phosphates )

l 0.75

0.50

0.25

Total Phosphate (mg/ 0.00

V2 top0 V17 top49 top45 top37 top24 top10

Figure 8: Phosphate changes from Lethabo weir to the Barrage (Box & Whisker plots).

Nitrate 3.0 ) l 2.0

1.0 Nitrate (mg/

0.0

V2 top0 V17 top49 top45 top37 top24 top10

Figure 9: Nitrate changes from Lethabo weir to the Barrage (Box & Whisker plots). 65

Solutions.

Two management options (hydrological and phosphorus control) were considered by Steynberg (1986) to maintain an annual average raw water chlorophyll standard of 20µg/l. Hydrological management implies the maintenance of riverine conditions in the Barrage reservoir with short retention times and a small Klip:Vaal River ratio. This management option is impractical due to the shortage of water in the Vaal River catchment area. The phosphorus management strategy involves implementation and maintenance of the 1mg/l ortho-phosphate standard sewage effluents in the Suikerboschrant and Klip River catchments. The application of this phosphorus standard will result in maintaining the annual average raw water chlorophyll and ortho-phosphate concentrations respectively below the 20mg/l and 440mg/l requirements up to the year 2000 (Steynberg, 1986).

Heath et. al (1998) reported that the implementation of the 1mg/l phosphate standard has resulted in a 47% decrease in the ortho-phosphate load released from waste water treatment works over the previous 10 years. This reduction is less than expected due to the large number of waste water treatment works still not complying to the standard. The reason for the introduction of the ortho- phosphate standard was to reduce the available orto-phosphate required for algal growth and to change the nitrogen to phosphorous ration (N:P) as both these options should reduce the algal biomass. The nitrogen values in the Barrage reservoir have increased due to greater sewage return flows, ina dequate maintenance and overloaded systems in rapidly urbanising areas. This has resulted in increased N:P rations which in turn has assisted in selecting for different genera of algae. The Cyanophyceae and the Chlorophyceae increased dominance has resulted in increased incidents of taste and odour problems with concomitant possible toxic blooms.

The future success of the control of the algal growth in the Barrage reservoir will be dependent on 100% compliance to the phosphate standard as well as possible future lowering of the standard. Coupled to this there needs to be a renewed effort in diffuse source reduction through catchment authorities (Heath, et. al. 1998).

7.3 Biological Status 66

7.3.1 Microbiological

The Barrage reservoir water is analysed weekly for bacteriological quality, and results are published widely to warn recreational users of the water of possible health effects. An example of the weekly report is attached as Appendix 2.

During the period October 2000 to November 2001, the water in the reservoir was unfit for full water contact sport for 91% of the time below the confluence with the Klip river. In the lower sections of the reservoir, the figure was between 26% and 57% (Appendix2).

This is a direct result of the high volumes of treated (and untreated) sewage entering the reservoir through the Klip river, the clarity of the water and the long residence times in the reservoir.

7.3.2 Hydrobiological

Algae are common inhabitants of surface waters exposed to sunlight which have the ability to impart odours and tastes to the water and to clog sand filters. They are also recognised as important factors in water supplies because of their capacity to modify the pH, alkalinity, colour and turbidity. One of the principal reasons for the importance of algae is their ability to give rise to large quantities of organic matter in the water. Algal blooms in open water bodies can be the cause of complaints by persons using the water for recreation purposes, and they may also cause fish mortalities by depleting oxyge n when they decompose (Pieterse, 1986).

Pretorius studied phytoplankton primary productivity in the Vaal Barrage during 1974/75, and found that primary production in the Vaal Barrage was controlled by turbidity (Pieterse, 1986). This was confirmed by Quib ell (1991), who further found that, when turbidities are low, algal growth is nutrient limited. Winter blooms tend to be phosphate limited and summer blooms nitrogen limited. The availability of silica also appears to limit the growth of diatom algae towards the end of winter.

The presence of algae in the treatment and supply of raw water for domestic use cause mainly interference with the treatment processes and in distribution systems. The algae may also pose a health hazard and impair the aesthetic quality of the potable water supplied especially if anaerobic decomposition occurs (Pieterse, 1986).

Annual reports of Rand Water (1945-1984) indicate that algal related problems were experienced since 1945. Algal blooms were reported in the Barrage reservoir from 1958, while taste and odour problems in the treated water apparently occurred from 1963.

Orthophosphate and nitrate plus nitrite concentrations in the Vaal Dam are lower than those in the middle Vaal River, and operation of the 600 mg/l TDS blending option will lower the concentration of these constituents in the Vaal Barrage. As turbidity will also decrease, the operation of the 600 mg/l option is unlikely to exacerbate the eutrophication problem in the middle Vaal river, and may even alleviate some of the problems experienced (Quibell, 1991).

An overview of chlorophyll-a concentrations and dominant algal species during September and October at the Vaal River Barrage are presented in Tables 8,9,10 and 11 below.

Table 8: Chlorophyll-a concentrations and dominant algal species in the Barrage for .

Period Chlorophyll-a (mg/l) Dominant Algal Species Possible purification problems

Mean Maximum Minimum 03/10/01 60 114 - (0kmT) 13 (40, 45 kmT) Centric diatoms Filter clogging Cryptomonas sp Taste and odour Chlamydomonas sp Taste and odour Microcystis sp Taste and odour 17/09/01 36 63 - (30kmT) 0.58 (5 kmT) Centric diatoms Filter clogging Aulocoseira sp Filter clogging Chlamydomonas sp Taste and odour Cryptomonas sp Taste and odour

Table 9: Average chlorophyll-a values at the Vaal River Barrage.

Period Average chlorophyll-a (mg/l)

Mean Maximum Minimum September 2001 88 223 – (30kmT) 1.5 – (0mT) October 2000 52 117 - (0 kmT) 7.4 - (40 kmT) Loch Vaal

Table 10: Chlorophyll-a values and dominant algal species in the Loch Vaal.

Period Chlorophyll-a (mg/l) Dominant Algal Possible purification problems Species Mean Maximum Minimum 03/10/01 127 209 - (LV10) 16 - (LV6) Centric diatoms Filter clogging Pennate diatoms Indicator Organic Pollution 17/10/01 129 162 - (LV8) 80 - (LV6) Centric diatoms Filter clogging

Table 11: Average chlorophyll-a values in the Loch Vaal.

Period Average chlorophyll-a (mg/l)

Mean Maximum Minimum September 2001 128 209(LV10) 16 - (LV6) October 2000 61 111 - (L10) 7.7 - (LV6)

Figures 10 and 11 indicate the algal species composition and the chlorophyll-a values in the Barrage reservoir. Figure 10 again indicates the sharp rise in algal biomass from km37, which relates positively with the chlorophyll-a trend depicted in Figure 11.

18000 120 16000 100 )

14000 l 12000 80 (ug/ 10000 a 60 8000

Algal cells/ml 6000 40

4000 Chlorophyll- 20 2000 0 0 0T 5T 10T 20T 24T 30T 37T 40T 45T 47T 49T

Centric diatoms Cryptomonas sp Total Algal Units Chlorophyll-a

Figure 10 : Algal biomass concentration of the dominant species in the Barrage Reservoir

Chlorophyll-a (1984-1999)

900 800 700 600 500 400 300 200 Chl-a (ug/l) 100 0

V2 top0 V17 top49 top45 top37 top24 top10

Figure 11: Monthly mean chlorophyll a values in the Barrage reservoir (Box & Whisker plots).

7.4 Physical and organic properties

The phys ical and organic characteristics of the reservoir are illustrated in Figures 12, 13 and 14. Figures 12 and 13 illustrate the improvement in clarity brought about by the impact of Lethabo weir (at about 50km upstream of the Barage) and the inflow of clearer water from the Klip and Suikerboschrant rivers, while the trend in the COD depicted in Figure 14 confirms the impact of the Klip and Suikerboschrant rivers .

The combination of improved clarity and high phosphate loads are major factors in the occurrence of algal blooms in the reservoir.

Secchi (1984-1999) 80

) 60 l

Secchi (mg/ 20

0km 49km 45km 37km 24km 10km

Figure 12: Mean monthly Secchi disc readings in the Barrage reservoir (Box & Whisker plots).

Turbidity (1984-1999) 150

100

50 Turbidity (NTU)

V2 top0 V17 top49 top45 top37 top24 top10

Figure 13: Mean monthly turbidity values in the Barrage reservoir (Box & Whisker plots).

)

l Chemical Oxygen Demand (1984-1999)

Chemical Oxygen Demand (mg/ V2 top0 V17 top49 top45 top37 top24 top10

Figure 14: Mean monthly COD values in the Barrage reservoir (Box & Whisker plots).

7.5 Pollution Events.

One of the main strategies to achieve water quality objectives is to address pollution at source. It is therefore essential to identify the most significant pollution sources and quantify their relative impacts so that appropriate pollution abatement strategies can be implemented. 72

Previous studies (Stewart Scott Inc, 1993) have shown that the 8 600 km² Vaal River Barrage catchment contributes about half of the salt load generated by the entire 108 000 km² Vaal River catchment down to Bloemhof Dam. Up to half of the salt load generated in the Vaal River Barrage catchment is derived from diffuse sources. Thus, both point and diffuse pollution sources need to be addressed if an effective management plan is to be realised.

Point sources are generally defined as comprising readily identifiable discharges that can be quantified. Discharges from wastewater treatment works and mine water discharges fall into this category. In many instances, diffuse sources are really the aggregation of numerous small or intermittent point sources that cannot easily be quantified.

A number of point and diffuse sources of pollution occur in the Vaal River Barrage catchment. These include gold and coal mining, industrial and agricultural activities, formal and informal urban areas and atmospheric pollution sources. The most direct threat of industrial pollution originates in the Sasolburg complex, an intensely developed area of large scale petrochemical, fertiliser and other relevant chemical industries, situated in close proximity of the Barrage reservoir, with discharges into the Taaibos and Leeu Spruit which drain into the Barrage reservoir.

7.5.1 Point Pollution Sources

Figure 15 indicates the industries, sewage treatment works and other major point pollution sources which discharge into the Vaal River Barrage catchment.

For the purposes of this study, the Vaal Dam should be treated as two distinct point source inputs to the Vaal River Barrage catchment. The first of these will comprise raw water abstractions from the Vaal Dam, either directly (such as the abstractions by Rand Water) or indirectly (via water abstracted from the Lethabo weir). The second pseudo point source comprises spillage (which is driven by upstream catchment runoff and inter-basin water transfers) and releases (which are driven by downstream water demands) from the Vaal Dam.

Figure 15: Most critical pollution point sources in the Barrage catchment. 75

Both the Vaal Dam abstractions and releases are strongly influenced by system operating rules, some of which are specifically aimed at meeting water quality objectives in the Vaal River Barrage and the downstream Middle Vaal River. Consequently, interaction will be required between Vaal River Barrage catchment water quality objectives and system operating rules, which will in turn affect Vaal Dam release patterns.

During the course of a water quality study of the Klip River undertaken for the Greater Johannesburg Transitional Metropolitan Council, it was found that from 1985 to early 1994 the base flow in the upper Klip River increased by about 60 000 m³/day, with a further 30 000 m³/day increase in the Natalspruit/Rietspruit catchment (Stewart Scott Inc and Pulles, Howard and de Lange Inc, 1995). The observed increase in base flow was found to be attributable to a combination of raw sewage overflows and water main leakage in the Greater Soweto, Johannesburg CBD and various East Rand townships. Although the geographical spread of individual spillage events within an urban area varies as repairs are affected and new leaks appear, the overall effect in terms of the hydrology of the main sub -catchments is a relatively steady input. It is therefore proposed that spilla ge/leakage inputs are treated as pseudo point source inputs to each sub- catchment. Such inputs can exhibit both discontinuities and trends. For example, a sudden almost step wise increase in spillage input was observed to occur during 1985 when Soweto and other townships became “no go” areas following political unrest that prevented sewer and water main maintenance. During the first quarter of 1995 a sharp downward trend in the spillage from the Greater Soweto area resulted from a concerted effort to repair sewer lines. Careful analyses of hydrological records and co-ordinated field flow gauging and water quality monitoring is required to quantify such inputs from urban areas.

7.5.2 Diffuse Pollution Sources

Non-point, or diffuse, sources of pollution enter ground and surface waters as a result of a diverse set of land use activities. A deterioration in water quality can occur following runoff from urban development, agricultural, mining and construction activities. Diffuse pollution is frequently both difficult to source and quantify and consequently has not yet been deeply researched. Typical 76 pollution contributions from diffuse sources include dissolved salts, nutrients, sediments, oils, pathogens and pesticides.

Resulting from the relevant legislatio n discussed in Chapter Five and the water quality status described in Chapter Seven, Rand Water developed a series of policies and management strategies to manage the reservoir in an integrated and holistic fashion. These are described in Chapter 8.

8. IMPOUNDMENT MANAGEMEN T.

As stated previously, the Vaal River Barrage reservoir (VRBR) was constructed by Rand Water in 1923 for the purpose of ensuring an adequate raw water supply to meet the potable water requirements of the Pretoria, Witwatersrand and Vaal Triangle regions. Today this is still the main purpose of this body of water, although it is by far not used as such, but is rather maintained as an emergency storage supply.

It is apparent that the very nature of the Barrage reservoir and its drainage area is in conflict with conservation. The reason for this is that most rivers and streams draining this area are intermittent and are dependent on treated waste water for most of their flow, especially during the dry season. The Barrage reservoir is also not a "natural" system but an intervention and serious disruption of the natural ecosystem by man which can never be reverted to its original state - a perennial river with seasonal fluctuations in water level, flow velocity and chemical composition.

8.1 Description of the Vaal River Scheme.

In accordance with the instructions of the Board to the Chief Engineer in 1911, surveys of all the catchment areas within a radius of 80 kilometres from Johannesburg were carried out with a view to the development by the Board of a permanent source of water supply for the Rand. These investigations occupied a period of about two years, at the conclusion of which reports were submitted to the Board dealing with 58 different schemes. After careful consideration of these reports, the Board, in September, 1913, selected the Vaal River Scheme, the construction of which has been carried out in accordance with the powers conferred on the Board by the Rand Water Board Supplementary Water Supply (Private) Act No 18 of 1914. The more important features of the scheme in question are dealt with hereunder.

8.1.1 Impounding Reservoir

The construction of the Vaal River Barrage reservoir structure across the Vaal River, 37 km downstream of Vereeniging, has had a dramatic impact on the Vaal River System in that it: 78

§ Created an impoundment § Impounded highly enriched and contaminated water with all its associated problems such as eutrophication, mineralisation and health related problems created a large and shallow lake in the Loch Vaal, which has become a serious problem due to stagnation of water and excessive algal blooms § Created a highly sought after residential area due to the stable water level in the Barrage reservoir § Created a much sought after recreational site § Established one of the few economic growth centres in the Emfuleni (Vaal Triangle) region § Changed the flow regime of the river system (Rand Water, 2001b).

The construction of a Barrage across the Vaal River, has created a storage reservoir in the bed of the river, which is capable of impounding 62 000 million litres (sixty two thousand megalitres) of water. At current supply (3 000 Ml/d) this equals about 21 days of storage capacity. This quantity is divisible as depicted in Table 12.

Table 12: Allocation of water stored in the Barrage reservoir.

Megalitres

1. Quantity which may be abstracted annually by the Board 33 186 2. Quantity for use of the owners of land riparian to the reservoir, in terms of Section 3 (2) of Act No 18 of 1914 7 092 3. Allowance for losses due to evaporation and absorption 15 375

4. Quantity in river bed below the level of the suction pipes at the Board’s River Intake Pumping Station, Vereeniging 6 323

Total Capacity of Reservoir 61 976

The dimensions of the reservoir, when filled to its maximum capacity, are depicted in Table 13. 79

Table 13: Dimensions of the Vaal River Barrage reservoir.

Length ...... 64.36 km Greatest Width ...... 1 220 m Submerged Area ...... ….. 16,83 km2 Depth of Water: At Barrage...... 7,65 m At River Intake Pumping Station, Vereeniging …… 5, 185 m

Like many South African rivers, the Vaal carries large quantities of silt during flood periods. In the course of an average year, about 453 916 m3 - equal to one million two hundred thousand tons - of silt are carried down the rive r past the Barrage (Rand Water, 1923). With a view to avoiding the accumulation of silt in the reservoir area, the barrage type of structure, consisting of a series of sluice gates, was selected for damming the river. This design also affords the greatest measure of control in regards to the passage of large floods through the reservoir and avoids the attendant risk of damage to private property along the banks of the river within that area.

8.1.2 The Barrage Structure

The original width of the river at the Barrage site was 189,1m, but the length of the Barrage is 429m. The object of cutting into the banks of the river to such an extent was to increase the waterway so as to compensate for the area taken up by the concrete piers and gate area in case of injury to the gates, so that no question could arise in future in regard to the obstruction of the natural flow of the river during high floods. The additional waterway is approximately 40 percent greater than the largest flood area.

A concrete apron covers the river bed for the entire length of the Barrage and for a width of 30,5m. This apron is necessary to prevent erosion of the foundations, and is carried for a distance of 13,7m down-stream of the piers. The velocity of the water, with a full reservoir, when a gate is raised 80

130cm is about 11,6m per second, and the erosive effect of such a velocity is exceedingly great.

On the down-stream edge of the apron a dwarf wall, 1m high, has been constructed to form a water cushion at the back of the gates, so as to break the velocity of the water when the gates are being opened. Cross walls have also been built at every fourth pier to prevent cross currents.

The Barrage consists of a series of piers with large mild steel sluice gates erected between the piers. There are thirty-five piers and two abutments, thus giving thirty-six openings, which are closed by thirty-six gates.

8.1.3 The Barrage Gates

The steel sluice gates closing the openings are 7,625m high and 10m in width, closing a 9,15m opening between the piers.

Provision has been made to raise the gates about 1,936m above the highest known flood level, which occurred in November, 1917, when a depth of 8,08m was recorded at the Barrage site.

The principal particulars of the Barrage are listed in Table 14.

Table 14: Particulars related to the construction of the Barrage.

Excavation ...... 210 375 cubic metres (m3) Stone cruhed for concrete ...... 32 895 m3 Sand ...... 15 759 m3 Concrete ...... 31 365 m3 Cement ...... 11,000 tons Material transported to the Barrage from Vereeniging ..... 21,000 tons Length of reservoir ...... 64 km Contents ...... 61,900 Ml 81

Number of gates ...... 36 Depth of water at Barrage ...... 7,65 m Net size of gate opening ...... 9,15 m wide by 7,625 m deep Weight of each gate ...... 26 tons Total weight of each gate and appurtenances ...... 100 tons Length of Barrage ...... 427 m

8.1.4 Technical Information

Surface Area of the water : ± 1 240ha Average Depth : 4 m

1 296 000 Ml/year enter Barrage reservoir. 845 000 Ml/year are abstracted 450 000 Ml/year are released 432 000 Ml/year do no t reach reservoir due to irrigation and other abstractions Catchment of barrage = 4,5% of total Vaal River catchment, contributes 7,8% of total MAR

8.2 Management activities aimed at achieving the fitness for use of water in the Barrage reservoir.

8.2.1 Routine monitoring of the Barrage Reservoir

The purpose of the routine monitoring programme is for Rand Water to keep informed of the status of the water quality and to collect enough data to allow for the effective statisitical analysis of the data for the production of water quality audit reports and to make predictions about future trends in water quality (See 6.2.1 and 6.2.2).

8.2.2 Problem Centered Sampling

Apart from routine samples, special samples are also taken on an ad-hoc basis. Staff have to rely on their specialist knowledge and experience to determine the need for special samples to be taken. Special samples are collected as a result of pollution incidents such as spills, or as an investigative measure where foul play is suspected. Result s of analyses are usually returned to the relevant industry and measures to improve the situation are discussed with senior personnel. In certain cases legal action may be taken.

8.3 Development control

8.3.1 The Vaal River Complex Guide Plan / Urban Structure Plan

The land use provisions of Chapter 5 and the development requirements of Annexure C (Appendix 3) of the Guide plan, have been drawn up with the purpose of regulating and controlling development along the shores of the Vaal Dam and the banks of the Vaal River. It is essential that, as a protective measure to lessen the risk of possible pollution, population densities in the area should be controlled.

The Guide Plan was not intended to be a detailed planning document (see 5.5). It was aimed at formulating an overall planning policy to serve as a framework for further planning action at provincial or local government level. In this regard the emphasis fell mainly on the identification of those land uses which have a decisive influence on the future spatial structure. Guide Plans thus serve as the framework within which physical planning must take place at urban and regional levels, and within which development priorities will be determined.

Annexure C of this Guide Plan provides some protection against pollution by setting specific statutory enforceable requirements in respect of riparian development along both the Vaal Dam and Vaal River Barrage reservoir. Rand Water performs a valuable function in the enforcement of these guidelines through regular patrols and inspections along the banks of both these water bodies.

The prescriptive method of limiting development on the banks of the Barrage reservoir has been applied for many years and has successfully protected the reservoir against pollution and flooding. 83

As the reservoir is essentially a potable water storage reservoir, the importance of water quality and at the same time responsibility to the property owners along the banks of the Vaal River Barrage with respect to flooding are paramount.

Amongst the requirements of Annexure C, the provisions of clauses 2.1, 2.2 and 2.10 are viewed as the most important insofar as Rand Water is concerned. Clause 2.1 in essence restricts development by not allowing habitable buildings or structures within the 100m open space area.

In addition, clause 2.2 restricts development by not allowing habitable buildings or structures below the 1975 flood control line. These are illustrated in Figure 16.

Vaal River Vaal River

1975 flood line

100m 100m

1975 flood line

Figure 16: Existing Guide Plan Restrictions.

Clause 2.10, however, affords Rand Water the discretion to consent to the relaxation of any provisions of Annexure C. For this reason, Rand Water, in 1987, developed internal guidelines to assist officials in cases where Rand Water had to exercise its discretion to relax the requirements of Annexure C of the Guide Plan. A copy of these guidelines, with amendments, is attached as Appendix 4. 84

Rand Water’s present policy on raising floor levels of habitable structures (on stilts) to above the 1975 flood level is limited to situations where there is no building site available above the 1975 flood control line on which suitable habitable structures can be built. Construction nevertheless must take place on the highest possible point on the property involved. Furthermore, in terms of the existing policy, structures below the 1975 flood control line may be enlarged by up to 15% of the floor space or up to a maximum of 50m2, whichever is the least.

· Proposed new policy

Insofar as the development of structures within the 100m open space area is concerned, Rand Water has for a number of years been faced with increasing pressure from developers and local authorities to change its development policy as set out above. Pressure has been mounting as to why ha bitable structures may not be allowed at a distance of 60m from the water’s edge, which from an assessment by Van Wyk (1996) would appear to provide an adequate cordon sanitaire. Pressure is also mounting to permit buildings raised on stilts above the flood level on all properties, regardless of the availability of ground in the erf above the flood control line. New guidelines along these lines suggested would not prejudice Rand Water in any way insofar present or previous legal action against any developers are concerned.

What has to be balanced against the pressure from developers is the long term interest of all who live in the vicinity of the Vaal River in this reach. It is common cause that the present flood line is for a recurrence interval of 34 years, which is less than the national guideline of a 1:50 year flood line for development purposes. A study by Stephenson (2000) also determined that the flood line is now actually corresponding to a 1:18 year flood line, due to development in the catchment.

The proposed changes to the policy would enable Rand Water to; · Approve of habitable buildings or structures at a distance of 60m from the water’s edge, and · Approve of structures raised on stilts with the floor level raised above the 1975 flood level.

In such as scenario the following criteria would be applied; 85

· Development be not less than 60m from the water’s edge · The floor level of the structure be raised on stilts to above the 1975 flood level · The sanitation or sewage removal system be approved by Rand Water · The structure should have no impact on floodwater, i.e no back-up is caused · The structure poses no pollution hazard, and · The developers provide Rand Water with a suitable indemnity registered against the title deed of the land.

A benefit from the implementation of the proposed policy would that existing legal structures situated below the 1975 flood line are demolished and replaced by structures on stilts above the flood level, but below the 1975 flood control line. This would increase the flow of waters, since obstacles would be partly removed.

The proposed new policy is illustrated in Figure 17.

Vaal River Vaal River

1975 flood line

60m 60m

100m

1975 flood line 100m line

Relaxation No Change

Figure 17: Proposed Guide plan restrictions.

8.3.2 Flood line protection. 86

The Vaal River and Wilge River which flow into the Vaal Dam upstream of the Barrage are the main contributors of water and the main source of floods. There are however other tributaries downstream of the Vaal Dam, namely the Taaibos spruit, the Suikerboschrant, the Klip, and the Riet spruit. Some of these rivers take return flow from Gauteng and the Vaal Triangle area so that the flow through the Barrage and downstream is considerably different to flow entering the Vaal Dam (Stephenson, 2001).

The Barrage backs up water past Vereenigin g, Vanderbijlpark and Sasolburg. Water levels along the river are controlled by the Barrage gates as well as inflow from the tributaries and the Vaal Dam. Flows, particularly in time of flood, are liable to spill onto the banks of the river and there is development along a considerable length of river, which could be affected by floods. There have been occasions where property has been flooded owing to high water level in the river (Stephenson, 2001).

Buildings along the banks of the Vaal and trees tend to obstruct flow during floods and cause the water to back up behind those obstructions with consequent hazardous effects on other property upstream. A backwater is created, i.e. the blocking of the flow path increases water depth upstream and this effect can be felt for a few kilometres upstream (Stephenson, 2001).

To ensure safety of riparian owners in flood events and minimise pollution of the reservoir, Rand Water has been pro-actively developing measures to ensure that the implementation of the Guide Plan is done consistently without compromising property owners’ rights to develop their properties for their own convenience. In this regard international flood management policies are studied and compared, and the most applicable aspects are built into Rand Water’s own management system. During 1996 and 2001 a comprehensive study was undertaken to enhance Rand Water’s decision- making capacities based on recent applied research, and a new policy regarding development within flood lines were developed.

Paragr aph 2.2 of Annexure C of the Structure Plan (Appendix 3) restrictions on development reads as follows; 87

“Except with the written consent of Rand Water Board no habitable buildings or structures, toilets, french drains, conservancy or septic tanks, sewage pumping installations or sewage works shall be permitted below the flood control line, as defined.”

The flood which occurred in 1975 was the highest recorded and was originally estimated to have a recurrence interval of 34 years. That is, from a statistical analysis of flood flows in the Vaal River, it was found that there was approximately a 3% chance that that flow could be exceeded in any one year (Stephenson, 2001).

As the Vaal catchment becomes developed with towns and industries, flood flows will tend to increase. This is because the construction of impermeable roads, roofs and reduction of natural ground cover, act to reduce infiltration and increase the proportion of rainfall which runs off to the rivers. In addition, the smoother roads and storm water conduits concentrate the water faster and therefore a higher flood peak can be expected (Stephenson, 2001).

In an attempt to ensure that valuable land is not isolated from development due to the position of the flood line, an integrated approach is followed by Rand Water. This implies that a trade-off could be made between the implications of flooding and the implications of prohibiting development within the flood zone.

The cost of not permitting development in the flood zone will increase over the ye ars as attractive river bank land becomes scarcer. An economic balance between the average hazard cost and the availability of land is needed (Stephenson, 2001).

The decision as to the level of development on the banks of a river and how close to the river depends on what the effect of the development will be on the flood as well as what the effect of the flood is on development. The following factors will affect the decision (Stephenson, 2001);

· What the effect of development will be on flood levels · What a flood will do to the development · How the value of the new and existing development is affected 88

· What the damage cost will be · What pollution threat there is to the water · The risk of adverse effects.

Stephenson and Hoge (1999) and Stephenson (2001) proposed the method to adopt is to define different zones, each with different limitations in terms of development. These zones are proposed as;

· Waterway: no development permitted, except possible channel improvements · Flood Plain: development only if it is advantageous and proved not adverse · Flood Fringe: development allowed at developers risk.

The definitions of the various zones are attached as Appendix 5.

Through its involvement in the enforcement of the Guide Plan, which focuses strongly on development within the flood line, Rand Water has become a highly valued body and source of information to other authorities as well as the general public residing within the Vaal Triangle. The implementation of the Guide Plan has been highly effective, although often opposed. Flood damage was minimal during the 1995/96 flood, mainly as a result of the proper, consistent application of the Guide Plan.

During the 1995/96 flood, an information center was also established at a local shopping mall and manned for more than a week. Staff were in contact with the SAPS, Traffic Department, DWAF, Civil protection, River Property Owners’ Association, the media etc., and were commended by the general public as well as a number of formal organisations on the efficiency of the information center.

Information regarding water levels in the Vaal Dam and Barrage, as well as the outflows from the reservoirs are obtained on a daily basis throughout the year, and disseminated as requests are received.

Recommendations for improved flood line Management (Figure 18). 89

i Development in the waterway should be prohibited as it is dangerous to developers and will obstruct floods. The waterway corresponds to the 10 year frequency flood lines. ii Restricted development may be permitted on the flood plains , i.e. between the waterway and the 1975 flood line, currently estimated to correspond to a 25 year flood line (during the 1975 flood, the flood corresponded to a 1:34 year flood). Restricted development includes construction on stilts to raise floor level above the 50 year flood level. iii At-risk development may be permitted on the flood fringes, i.e. above the 25 year flood line.

Vaal River Vaal River

1975 flood line

60m 60m

100m

On Stilts 100m 1975 flood line No Change

Figure 18: Proposed new policy for development within flood line.

8.3.3 Sanitation systems evaluation

In accordance with Clause 2.2 of the Guide Plan, Rand Water inspects all building operations and in fact, needs to approve building plans to ensure no pollution emanating from septic tank and french drain systems riparian to the reservoir will pose a threat to the water quality in the reservoir. The Guide Plan introduced a cordon sanitaire of 100m but research by Van Wyk (1995) indicated that a distance of 60m would suffice. This implies a distance of 50m from the water’s edge to the lowest point of the sewerage system, plus 10m to allow for the actual space occupied by the sewerage system (to the lowest point of the house).

Rand Water’s existing guidelines for sanitation systems are attached as Appendix 6.

8.4 Reservoir Maintenance .

8.4.1 Project Barley

The occurrence of unsightly and foul smelling masses of blue -green algal scums on the surface of the Loch Vaal is an annual occurrence offending riparian property owners, the general public using the area for recreational purposes, and Rand Water.

Limiting the cause, which implies the removal of plant nutrients such as phosphates and nitrates from the water, is not always feasible, especially in a highly industrialised and urbanised catchment such as that of the Rietspruit, which is the main source of raw water of the Loch Vaal. Treating the symptoms is equally difficult in that it would imply the application of an algicide on an area of 191 ha, which, in addition to being prohibitively costly and difficult to apply, may also affect no n-target species. The solution therefore lies in a combination of the two possibilities.

Based on laboratory research, it was determined that a dosage of 2.7g of barley straw/m3 of water would result in a 95% growth inhibition of blue -green algae. This dosage is equivalent to 2.4 bales of straw per hectare. As one bale weighs ± 20 kg, this is equal to 48 kg/ha in water that is on average ± 1m deep (IACR, 1997).

Since the summers of 1994/95 and 1995/96, Rand Water has been implementing the project on the Loch Vaal section of the Vaal River Barrage reservoir. Bales of straw in specially made steel baskets are strategically placed throughout the Loch along the original channel of the Riet spruit so as to obtain optimum exposure of the ambient water. Bales are loosened before being placed in the baskets to ensure aerobic conditions for active decomposition. To ensure efficient dosages, the baskets are filled during September, November and January, as it takes approximately 4 - 6 weeks for the barley to decompose properly. 91

Large vegetable bags are also filled with straw and tied to the undersides of the jetties of riparian property owners to augment the exposure ratio of straw to water.

Samples are collected by Rand Water on a two-weekly basis for chlorophyll-a and algal identification analyses. Chlorophyll-a concentrations remained typically high, although a definitive improvement in the aesthetic quality of the water was observed, indicating a shift in algal composition of the water. In this regard only, the exercise is a hugely successful public relations effort and is well worth the effort.

8.4.2 Rand Water property (marginal strip) management

When the Board constructed the barrage in 1923 it bought out the land to be inundated, as well as additional land on either side of the reservoir for possible future inundation and to enhance its control over the reservoir. Property owners pay a nominal fee of R 50 (plus VAT) to obtain the rights of access over and use of the marginal strip. Control over recreational structures constructed on the Board’s land (marginal strip) is one of the functions of the catchment management section (Appendix 7).

8.4.3 Aquatic Weed Control

Water hyacinth (Eichornia crassipes) and other plants such as Kariba weed, parrot’s feather and historically presented a problem in the Barrage and lower Vaal River as early as 1972 when considerable sums of money were spent to eradicate the problem. The hydrologically wet years from about 1975 to 1979 caused large floods in the lower Vaal River and this presumably exerted some control over the overabundant development of water hyacinth (Bruwer, 1986).

The water hyacinth, which is a floating plant, is pushed towards the banks of the river in flood where it gets trapped in the branches of trees or is deposited in the river banks. Large floods thus appear to dramatically reduce the visible biomass of water hyacinth. Some plants, however, must still be left as the hyacinth becomes re-established in watercourse again with time (Bruwer, 1986). 92

Natural low flows during the summer season of 1982/83 caused hyacinth to spread some 15km downstream of Orkney in the lower Vaal River. Man-made releases during the summer of 1983/84 caused hyacinth to spread a further 40km downstream. Subsequent releases and small natural floods from June 1984 to January 1985 caused hyacinth to spread a further 100km downstream, infesting Bloemhof Dam (Bruwer, 1986).

Problems caused by aquatic macrophytes.

· Interference with water supply

Eichornia has caused blocking of pump intakes, and systems have had to be redisigned to divert the hyacinth from intakes. If the hyacinth mat becomes so dense that it completely covers the river for large areas for extended periods, a lowering of the dissolve oxygen levels could occur. Bruwer (1986) reported a dissolved oxygen reduction from 8,1 to 4,2 mg/l under a hyacinth mat of 700m long.

Under these anaerobic conditions increased dissolved iron, manganese and ammonia concentrations would arise, resulting in treatment problems of water to pota ble standards.

· Interference with recreational water use.

Recreational use of water can be classified as full- (swimming, skiing), semi- (sailing, fishing) or non- contact (picnicking) use. Macrophytes have interfered with all three types of recreation along the Vaal. They obstruct access to, and movement through, the water. This can result in a loss of revenue generated from river associated recreational areas.

· Control

The adequate herbicidal control of infestation in 1985 was estimated to cost between R3,6 and R4 million, with annual follow-up costs of R 1 million (Bruwer, 1986). 93

A team of eight River Cleaners is responsible for clearing of exotic weeds, clearance of reeds where access to the river is restricted, removal of debris and drowned animals, clearing weirs and bridges from stuck trees and branches etc. and assistance with all other projects where manpower is required. Approximately 15 488 man hours are spent annually to remove trees from the reservoir, clean weirs, repair access codes, bury dead animals and assist with scientific project work.

8.5 Recreational activities control.

8.5.1 Boat density control

The fitness for use of a water body for recreational purposes can be described in terms of the effect on the health of the users, as well as in terms of aesthetic aspects. In both cases the eventual water quality objectives will depend on the nature and the level of the activity (Van Veelen and Venter, 1996).

Rand Water’s policy is to minimise the pollution risk related to recreational use of water, and to maximise the accessibility of use of the water for recreational purposes in the safest possible way for all. Management systems are therefore developed with the above as the main objective.

In 1987 Rand Water introduced a boat permit sys tem to limit recreational activities on this water body. The purpose of the permit system is to control the orderly and safe use of boats on the water, and to protect the water source against pollution and erosion. The water is made available to the public for their recreational use in an orderly, safe and secure manner. Care has to be taken at all times by the users of water craft that they do not endanger the lives of any other users of water craft, or swimmers in the water, and not to act to the annoyance of others. Boating is therefore allowed subject to certain rules (Appendix 8). Rand Water’s legal rights are explained in Appendix 9.

The total water surface area of the Vaal Barrage is 1240,35 hectares and the estimated boating portion is 882 hectares. A permit quota of 3350 power boats and 1800 "non-power boats" (sailboats, canoes) ensures that boating densities on the reservoir are kept within acceptable norms. 94

In addition, twenty commercial permits are available for operators with pleasure cruisers. Each local authority have five permits to allocate, while Rand Water retains the other five for allocation at its discretion.

Boat permits are sold on a first come first serve basis. Density figures are based on a factor of 1,2 ha per boat, assuming that no more than 20% of all permit holders will be at the Barrage at any one time. Day permits also sold at public slipways by part-time employed pensioners. Three officials patrol the river over weekends, inspecting boats for safety and permit validity.

The procedures to apply for a boat permit are attached as Appendix 10.

In terms of the rules, a permit is; · “valid for a period of twelve months from date of issue and will be renewable on each ensuing anniversary of such date …” · “issued in respect of a boat operating on the reservoir and shall attach to the owner of the boat …”

Outboard motors and water pollution.

A literature survey undertaken by Haynes (1984) concluded that there are completely divergent views as to the damaging effects of outboard motor products on the aquatic environment. Based on the findings various researchers concluded that outboard motors seem to run more inefficient at lower engine speeds than they do at higher speeds.

All substances emitted by outboard motors are derived from a fuel mixture that consists of gasolines with or without its additives and lubricating oil. Over 100 compounds have been identified in gasoline, these include normal and branched alkanes, cycloalkanes, and alkylbenzenes.

Jackivicz (in Haynes 1984) states that of all the possible oxidation products that could be formed from the partial oxidation of fuel in both two and four stroke engines, phenolic compounds would possibly be the most troublesome from a pollution point of view. 95

The EPA concludes that if 3 000 rpm is selected as the speed at which most boat usage occurs and the values of total condensable aromatics as a percentage of fuel is averaged over all engines tested, a figure of 2,5 percent condensable aromatics is obtained. Thus it is concluded that the “average” engine will contribute about 2,5 percent of its fuel to the water, exclusive of drainage, during most of the time it is in use.

The EPA found, in test ponds stressed at levels far in excess of normal boat usage that no significant evidence of fish tainting was observed during the study. They also observed that there were no significant variation in zooplankton or in phytoplankton species richness, caused by outboard engine operation in the test ponds under study. Furthermore evaluation of macrophyte communities with regard to productivity was done and they state that no statistical difference in gross productivity was observed.

The EPA found that the aromatic constituents condensate to have an evaporation half life of about eleven days in a lake. They also found that under field conditions of aeration of the water body that the majority of the aromatic hydrocarbon remained in the water column for a relatively short time – less than a day – before being removed by natural physical (evaporation), chemical (absorption) and biological (bio-oxidation) processes.

The estimated density for the extreme critical situation, according to English et. al (in Haynes, 1984) was one boat per surface area of 61m X 61m, with a volume of water per gallon of fuel consumed to be approximately 16 000 gallons (4 224 liters). For the critical situation a density of one boat per 152m X 152m and volume of water per gallon of fuel consumed to be 2 million gallons (528 000 liters).

The EPA considers saturation boating to be at the following boating densities: Water skiing = 12,14 hectare per craft Pleasure boating = 1,21 hectare per craft Fishing (static) = 0,4047 ha/craft Fishing (trolling) = 1,21 ha/craft. 96

Authorities in both Germany and the UK concluded that overall a boating density of one craft per hectare would be permissible.

8.5.2 Special sporting events control

Due to the high density of boating on ther reservoir, any organising body wshing to stage a sporting event on the reservoir has to apply for approval from Rand Water three months in advance. This is to allow Rand Water opportunity to inform all relevant authorities, boat clubs, the River Property Owners’ Association, SAPS etc. This done to ensure no double bookings of events take place, as well as to ensure that the water level and flow velocities are fit for the intended event.

The organising body must supply Rand Water with the necessary indemnity, and disclose all information required in the application form, which is attached as Appendix 11.

8.6 Conservation

The Vaal River barrage is essentially a potable water storage reservoir, and it is therefore imperative to protect the quality of the water at all cost. As the Barrage also supports a diverse ecosystem, it is only logical to combine nature conservation and pollution control efforts in an integrated environmental management approach to protect this invaluable body of water.

Following an integrated approach, Rand Water, endeavors to: i) achieve a continuing overall improvement in the water quality of streams, rivers and dams under its control. ii) manage water resources to try and obtain a balance between the needs of the environment, financial constraints and industrial pollution abatement technology. iii) protect the natural environment for the beneficial use of the community at large and to sustain and improve a healthy source of raw water. 97

As the owner and custodian of the VRBR, every attempt is made to protect sensitive areas such as bird nesting and roosting sites and some of the tributarie s of the barrage have been closed off and no speeding or water skiing is allowed to provide nature lovers to idle up these creeks, enjoying the surroundings to the full.

The boat permit rule book also provides for the considerate use of water craft so as not to disturb the natural environment

In view of the above and realising the recreational potential and the need to conserve the Vaal River Barrage reservoir for all, the concept of a VAAL RIVER BARRAGE CONSERVANCY was born. Various options and alternatives were investigated to obtain the most suitable management structure plan.

Although a conservancy does not have the legal standing of a nature reserve, it is envisaged that by encouraging riparian property owners to voluntarily participate in the manage ment of the conservancy, the same or even higher standards of control can be achieved than by legally enforcing regulations upon them in which they did not participate in formulating.

9. WATER QUANTITY CONTR OL MEASURES.

9.1 Weirs

A total number of six weirs are maintained on tributaries entering the Barrage reservoir. These weirs are visited at weekly intervals to service the flow recorders and carry out general inspections on the condition of the weirs. All weirs are equipped with flow recorders, and readings are returned to the laboratory for electronic capturing of the recordings. Continuous recording to assist with maintaining normal operating levels and planning in flood situations.

The total flow over all six weirs are used in combination with the volumes released from Vaal Dam to calculate the amount to be released from the Barrage.

Daily outflow from Barrage

600

500

400

300 FLOW Flow (cumec)

200

100

0 01-10-00 15-10-00 29-10-00 12-11-00 26-11-00 10-12-00 24-12-00 07-01-01 21-01-01 04-02-01 18-02-01 04-03-01 18-03-01 01-04-01 15-04-01 29-04-01 13-05-01 27-05-01 10-06-01 24-06-01 08-07-01 22-07-01 05-08-01 19-08-01 02-09-01 16-09-01 30-09-01 14-10-01 28-10-01 Date

Figure 19; Daily outflow from the Barrage for the period October 2000 to October 2001.

9.2 Normal operating procedures for the Barrage gates.

100

The operating procedures for the Barrage are attached as Appendix 12. 101

10. INFORMATION MANAGEMENT.

To aim of all management activities is to ensure quick and effective decision-making, to minimise impacts of pollution and to allow proactive planning based on determined long term trends in water quality.

As the Barrage reservoir is bordered by three local authorities, and is used by industries, the public, riparian owners etc. for a variety of purposes, Rand Water needs to be in a position where information can be disseminated to interested parties as quickly and effectively as possible in an effort to educate the public and consumers regarding aspects relating to water conservation.

10.1 Modeling

The development of mathematical models as management tools in the prediction of floods, interrelated chemical reactions as a result of pollution incidents etc. can be invaluable when important decisions have to be made. Through these models, anticipated effects of various events can be simulated in advance, greatly enhancing the efficiency of effective decision making.

10.2 Geographic Information System and Catchment Information Decision Support System

The data/information generated by the monitoring program has little value if it is not related to a physical location in the catchment. This is especially true when managers have to make informed decisions, but are not familiar with the actual situation on the ground. The development of a GIS overcomes this problem as water quality information can be linked to other information such as land uses, rainfall, flow measurements, population statistics, effluent discharges etc. in a geographical context, allowing for the capacity to make quick and low- risk decisions without necessarily having to rely on a site investigation. The GIS enables one to place water quality information in a geographical context with other catchment related information.

102

Water quality information is downloaded to the CIMDSS and data for a specific sampling point can then be manipulated and evaluated. A vast variety of analytical queries and manipulations can be performed. Some examples are illustrated in Figures 20 and 21.

A complete record of each property and sub-division riparian to the reservoir is kept by means of digital aerial photographs, with the 1975 flood line and Rand Water’s property boundaries, pipelines etc indicated as overlays (Figure 22).

This technology enables Rand Water to make timeous and well-informed decisions based on recently updated information.

103

104

Figure 20: Example of CIMDSS Statistical Report. 105

106

Figure 21: Example of CIMDSS Time Series graph. 107

108

Figure 22: Example of riparian property GIS database. 109

11. CUSTOMER FOCUS INITIATIVES.

11.1 Education

Catchment staff are well equipped to address members of the public, the media, schools, universities, internal staff and other organizations requesting specific information from time to time.

11.2 Community Involvement.

Rand Water plays a major role in the activities of the following public bodies and organisations;

11.2.1 Vaal River Safety Association (VRSA) This association consists of the boat clubs, RPOA, the SAPS Water Wing and Rand Water, and has as it’s mission the promotion of safety on the river. 11.2.2 River Property Owners' Association (RPOA) The RPOA involves al owners of property riparian to the reservoir, and addresses issues such as safety, development, conservation. 11.2.3 Save the Vaal Environment (SAVE) A body established in the mid 1990’s to fight development along the Barrage reservoir that was seen as a threat to property values, quality of living and conservation of the area. 11.2.4 SAPS Water Wing A close working relationship has develop over the years with the Water Wing of the South African Police Services. The Water Wing assists Rand Water by patrolling the reservoir over weekends for normal law enforcement purposes. 11.2.5 Boat Clubs & Hotels The clubs and hotels situated on the banks of the reservoir play a crucial role in the control over boating on the reservoir. The rules of the clubs are complimentary to Rand Water’s boat permit system, and club committee members act as river wardens on the water in front of their respective clubs. 110

The clubs and hotels also form important links in the communication chain. Any information sent out regarding organised sporting events, flood dangers etc., are sent to these institutions who in turn inform their members and guests accordingly. 11.2.6 The Barrage reservoir Forum The Forum holds public meetings to inform stakeholders of developments in legislation, water quality , upcoming events etc. It also forms part of the CMA process and is represented on the Vaal Barrage Catchment Executive Committee. 111

12. CONCLUSIONS.

The Vaal River Barrage reservoir is essentially a potable water storage reservoir, and it is therefore imperative to protect the quality of the water at all cost. As the reservoir also supports a diverse ecosystem, it is only logical to combine nature conservation and pollution control efforts in an integrated resource management approach to protect this invaluable body of water. Rand Water is the most suitable body to implement the various acts and regulations.

13. RECOMMENDATIONS.

A Vaal River Barrage catchment management structure is required which Rand Water believes should not exceed three tiers - a National Authority (DWAF), a Catchment Co-ordinating Agency (CMA) and Regional Authorities. The national authority would ensure raw water supply, establish goals and water quality norms, as well as methodologies to determine receiving water quality objectives and waste allocation loads.

The co-ordinating agency would be responsible for providing potable water, the strategic planning of wastewater reclamation, the maintenance of a monitoring system and a GIS, aimed at supplying water quality data, issue permits for abstraction and discharges, and the approval of all development plans within the catchment to ensure wastewater plants and receiving water bodies can absorb the load.

Regional authorities (eg Local Authorities) would be responsible for supplying potable water, collecting and treating wastewater, monitoring compliance with standards and monitoring and preventing pollution.

Due to the strategic importance of the Vaal River Barrage catchment and the impact of activities in the catchment on water resources, it is seen as of the utmost importance for the above mentioned authorities to make a joint effort and co-ordinate action to solve problems in the catchment. In doing so, the proposed management structure should be set up, all shortcomings in each of the three 112 management tiers identified and prioritised and all existing catchment related information within the three tiers should be collated .

The promulgation of the Water Services Act during 1997 and the National Water Act during 1998, influenced the institutional setup responsible for the management of the Barrage reservoir, although it is not expected to change significantly, if at all, in the short to medium term.

The following issues are critical; i Continue blending ii Actively drive Forums = increased focus on problems, evoke Best Management Practices iii Initiate and drive a concerted move towards CMA establishment to ensure proper integrated management iv Preserve wetlands v Implement new flood policy vi Assess relevance of the various Acts, and ensure all management aspects are properly covered by empowering legislation.

“Perhaps our greatest salvation is that water, though used and used again, is indestructible – use it, pollute it, mix it with many compounds, bury it, evaporate it, it remains stubbornly water fortunately” (Laburn, 1979c).

Rand Water should ensure that adequate resources are available to implement the relevant legal requirements and strategies. Due to the complexities involved, staff should be multi-skilled to deal with the high technical level, the high level of public involvement, and media awareness. 113

REFERENCES.

1. Affidavit by F.P. du Plessis. RWB, VRSA, Eligwa club vs S.W. Ottens. In the High Court of South Africa (Transvaal Provincial Division). 2001.

2. Braune, E. 1986. Foreword. The Vaal River Ecosystem: Status and Problems . Proceedings of a joint symposium convened by the Foundation for Research Development and the Vaal River Catchment Association. CSIR, Pretoria.

3. Bruwer, C. 1986. Macrophytes in the Vaal River. Proceedings of a joint symposium convened by the Foundation for Research Development and the Vaal River Catchment Association. CSIR, Pretoria.

4. Department of Water Affairs & Forestry, 2001. Upper Vaal Water Management Area. CMA establishment. Status report. Gauteng Regional Office, Pretoria.

5. Department of Water Affairs & Forestry & Rand Water, 1993; Management Structure and Project Proposal for the Vaal River Barrage reservoir catchment. Pretoria.

6. Department of Water Affairs & Forestry, 1993. The South African Water Quality Guidelines. Pretoria.

7. Department of Water Affairs and Forestry & Rand Water, 1993. Management Structure and Project Proposal for the Vaal River Barrage Reservoir Catchment.

8. Department of Water Affairs and Forestry, 1999. A framework for implementing non-point source management under the National Water Act. Department of Water Affairs & Forestry, Pretoria.

9. Du Plessis, F. Personal Communication. 2001.

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10. Haynes, R.E., 1984. A review of outboard motor effects on the aquatic environment and pollution potential of water based recreation activities and riparian development along the Rand Water Board’s Barrage reservoir. Rand Water Board Internal Report.

11. Heath, R. et. al (1999). A synthesis of the sampling programme of the Vaal Dam, Vaal River Barrage and Loch Vaal and future monitoring recommendations . Rand Water. Scientific Services.

12. Heath, R.G., Steynber, M.C., Guglielmi, R., and Maritz, A. 1998. The Implications of point source phosphorous management to potable water treatment. Water Science & Technology, Vol. 37, No.2.

13. IACR . 1997. Information Sheet 3: Control of Lagae with straw. Centre for Aquatic Plant Management. UK.

14. Laburn, R. J., (1973); Some aspects of Water Management in the PWV Metropolitan Region. The Institution of Certified Mechanical and Electrical Engineers, South Africa. Kelvin House – 18 October 1973.

15. Laburn, R. J., (1978); Rationalization of water management in the Pretoria-Witwatersrand- Vereeniging complex, the Republic of South Africa’s most important urban, industrial and commercial region. S.A. Edition of WPCF Journal.

16. Laburn, R. J., 1979a; A Treatise on the Rand Water Board with special reference to its Responsibilities, Achievements and Policies during 75 years of operation. Rand Water.

17. Laburn, R. J., 1979b; Rand Water Board. IMIESA, May 1979.

18. Laburn, R. J., 1979c; Water Management in the Pretoria – Witwatersrand – Vereeniging -Sasolburg area. Keynote address to the University of Pretoria Summer School. January 1979. 115

19. Pieterse, A.J.H., 1986. Aspects of the ecology and significance of algal populations of the Vaal River. Proceedings of a joint symposium convened by the Foundation for Research Development and the Vaal River Catchment Association. CSIR, Pretoria.

20. Quibell, G. 1991. An investigation of a new operating strategy for the Vaal river system. Vol 2. The potential effects on the eutrophication of the middle Vaal River. Report number: N: C200/00RPQ2790. Dept of Water Affais & Forestry.

21. Rand Water & Department of Water Affairs & Forestry. Joint Venture. 1996; Vaal Barra ge Catchment. Water Quality Management Plan. Phase 1: Scoping Study.

22. Rand Water, 1923. Souvenir of the opening of the Vaal River Scheme.

23. Rand Water, 2001a. Annual Report 2000.

24. Rand Water, 2001b. Vaal Barrage Water Quality Objectives. Result of a workshop held on 29 June 2001.

25. Steffen, Robertson & Kirsten, 1993. Assessment of the feasibility and impact of alternative water pollution control options on TDS concentrations in the Vaal Barrage and Middle Vaal.

26. Stephenson, D. 2001. An integrated management strategy for the Vaal Barrage Area. University of the Witwatersrand, Johannesburg.

27. Steynberg, M. C. 1983. Algae and their consequences. Rand Water.

28. Steynberg, M. C., 1986. Aspects of the influence of eutrophication on the Vaal River barrage . Rand Water.

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29. Swart, M.C., 1999. A GIS solution for industrial problems in catchments. SSAG conference, Windhoek.

30. Van Baalen L., and Maritz, A. (2001) Report on the chlorophyll-a and algal idntification at the Vaal Dam, Vaal River Barrage reservoir and weirs for the period October 2001. Report nr: 01/10/26 P10 (H3). Rand Water.

31. Van der Merwe, S.W. 1984. The economic implications of water quality in the supply of potable water by the Rand Water Board. Proceedings of a symposium presented by the Vaal River Catchment Association. Pretoria.

32. Van Der Schyff, M. 2001. Personal Communication.

33. Van Rynefeld, M On-site sanitation survey of Barrage ????

34. Van Veelen, M. and A. J. Venter, 1996. Jukskei River Water Quality Management: Development of Water Quality Management Objectives. BKS Incorporated. Report number 104/97.

35. Van Wyk 1996: Onsite sanitation and groundwater pollution. Discussion document. Rand Water.

36. Viljoen, F. C., 1984. The necessity of phosphate restrictions in the Vaal River barrage catchment. Rand Water.

37. Water Research Commission. 1979. Water pollution and effluent reclamation in the Pretoria – Witwatersrand – Vereeniging – Sasolburg complex. Options for improving the mineral quality of the water supply. Volume 1. Pretoria.