Rand Water | Integrated Annual Report 2025

Quality of Water in the Vaal Barrage Reservoir

Date Sampled 25 June 2025

Riviera Hotel

Vosloo Park

3

Klip River

Suikerbosrant

Dickinson Park

1

Riviera Aquatic Club

FW De Klerk Bridge

2

VEREENIGING

SEBOKENG

Rietspruit

Railway Bridge

N

4

Vaal River

Village Manor

R59 Bridge

VANDERBIJLPARK

Ascot Bridge

Emfuleni Park

Eligwa Club

9

Lochvaal Club

Riverside Sun Hotel

5

Lethabo Weir

Upstream to Vaal Dam

6

Vaalview Aquatic Club

8

Vaal River

10

Baddrift Bridge

Vaal River

Clavadel Caravan Park

7

Abrahamsrust Resort

Downstream to Parys

Luciana Country Club

Taaiboschspruit

Not to Scale Toll Free No: 0860 10 10 60 Sample Point

Leeuspruit

SASOLBURG

E.coli counts per 100ml at sample points

Escherichia coli (E.coli)

1

2

3

4

5

6

7

8

9

10

Predicted symptoms include: Skin irritations, infections &

1,300

2,420

46

172

3,590

1,986

39

145

1,299,700

64

This

Week

intestinal disorders

11,780

1,300

15

8

4,870

16,240

105

161

312,300

15

Last

Week

Low risk gastrointestinal disorders E.coli ‹ 130 counts/ 100ml Slight risk of gastrointestinal disorders E.coli 130 - 200 counts/ 100ml

Significant risk of gastrointestinal disorders E.coli 200 - 400 counts/ 100ml High risk of gastrointestinal disorders E.coli 400 counts/ 100ml

Blue Green algea counts at sample points

Blue Green Algae Predicted symptoms include: Skin irritations, infections &

1

2

3

4

5

6

7

8

9

10

1,689

7,964

40

9,050

724

6,516

10,860

4,300,562 11,854

114,995

This

Week

10,860

24,737

483

26,547

40

79,399

46,457

93,396

8,504

41,871

intestinal disorders

Last

Week

Low risk Blue Green algae ‹ 20,000 cellls/ 100ml

Moderate risk Blue gren algae 20,000 - 100,000 cells/ ml

High risk Blue Green algae › 100,000 cells/ ml

Algal pigments expressed as Chlorophyll-a levels at sampl points

Algal Pigments Predicted nuisance conditions include: Scums & Smells

1

2

3

4

5

6

7

8

9

10

40

22

9

19

9

110

34

1,436

28

181

This

Week

13

29

68

19

12

200

108

316

42

79

Last

Week

Low risk Chlorophyll-a ‹ 15ug/l

Moderate risk Chlorophyll-a 15 - 30ug/l

High risk Chlorophyll-a › 30ug/l

Figure 22: Microbiological water quality of the Vaal River Barrage Reservoir

In line with its Water Quality Management System, Rand Water continuously monitors the catchment and informs Rand Water operations and stakeholders of raw water risks. Restoration of the Vaal Barrage Reservoir natural habitat The Vaal River Barrage Reservoir (VRBR), a 64-kilometre-long managed segment of the Vaal River System, is a vital part of South Africa’s natural capital. The VRBR covers a surface area of 168.35 km² and holds 63 million litres of water. The VRBR forms an essential ecological asset, providing habitat for aquatic species and supporting biodiversity. As a water body of strategic importance, its health and sustainability are directly linked to the wellbeing of communities and economic sectors reliant on this water system. In line with Section 116 of the National Water Act, an integrated plan consisting of the Integrated Biological Remediation Programme and the Local Resource Management Plan has been developed and is being implemented to preserve and restore this natural resource with reference to listed alien invasive macrophytes.

156

Rand Water | Integrated Annual Report 2025