Vargafon Sample Book 2

Water system in the Nelson Mandela Metropole A Photographic Documentation

by Dirk Moggee

Water system in the Nelson Mandela Metropole A Photographic Documentation

by Dirk Moggee

Contents Introduction Page 1 Churchill Dam Page 2 Bulkrivier Dam Page 20 Sandrivier Dam Page 26 Groendal Dam Page 38 Lower Van Stadens Dam Page 52 Kouga Dam Page 64 References Page 83

Introduction The demand for natural resources increases daily to provide for a growing population. The most common and most essential resource, water, needs to be preserved and cared for to ensure a sustainable future. Therefore the lack of development in infrastructure, in the Eastern Cape specifically, has become a reason for concern.

As quoted in Water Scarcity- The Food Factor (2007), by an Indian rural development worker, Salunkhe: “Water is the divide between poverty and prosperity”. This statement is not only valid in India, but worldwide, as no community can or will survive without water. Climate change together with a growing population puts stress on the current water system in South Africa. These factors ultimately put stress onto other natural resources. Without water, agriculture cannot provide food for humanity.

Water scarcity for food states: “The water people need for drinking is essential, but it is only about 0.01% of the water people require to produce their food”. (Molden et al: 2007). Therefore educating the public on water is as essential in solving water issues as the upgrading of water structures. Looking at upgrading of structures specifically, alternative ways of gathering and treating water needs to be looked at to ensure a sustainable water future.

Six dams was photographed as a documentation of the existing and working water supply in South Africa.

These Dams will include: Churchill Dam, Bulkrivier Dam, Sandrivier Dam, Groendal Dam, Lower van Stadens Dam and the Kouga Dam. All of these systems are situated around the Nelson Mandela Metropole in the Eastern Cape. Together with the documentation of Dams, the water treatment plants was also photographed, this includes the Churchill treatment plant and the Groendal treatment plant. These two systems are currently the main water treatment works for the city.

1

Churchill Dam The Churchill Dam, originating from the Kromme river, first completion date was in 1943, thereafter the buttresses of its multi-arch wall were strengthened and completed in 1961. Otherwise known as the Jan Christiaan Smuts Dam, is situated near Humansdorp in the Eastern Cape, South Africa. The Churchill Dam was the only buttress, multi-arch Dam visited during this project. This buttress Dam is built in a wide valley, this is however not the only situation buttress Dams are built in as research suggests that buttress Dams are suitable in both narrow and wide valleys, where the ground is of acceptable load bearing capacity. South African Dams states: “Forces placed on the wall by hydrostatic pressure are transferred to the buttresses which in turn transfer the force to the earth” (NA: 2013). Therefore this wall type is seen as safe and strong, however, this does depend on the stability of the ground built on.

Because of the wide valley this Dam is built in, the height of the wall is only 40 meters; the length thereof is 213 meters. This is considered as a large Dam and high-risk wall when considering the Dam walls volume of 75 000 m3.

Churchill Dam has its own water treatment works and sends treated water to the Nelson Mandela Metro.

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

Bulkrivier Dam Bulkrivier Dam, originating from the Bulkrivier was first completed in 1905, after realizing the potential of the Dam having a bigger capacity, the Dam wall was raised. These developments were completed in 1929. This gravity-arch wall Dam situated near Uitenhage in the Eastern Cape South Africa consists of an overspill section, reducing the pressure on the wall during overflow of the Dam. The name ‘gravity wall’ suggests that the wall relies on the gravity of the wall to support itself, and not allow the volume of the reservoir to push the wall over. A good foundation in this case is crucial for a long lasting low risk Dam. “Gravity Dams are suited to sites with either wide or narrow valleys, but they do need to be built on sound rock” (NA: 2012). The type of wall built for specific Dams, does make a direct comment on the soil and rock structure of the area. These decisions are made during the selection process of the Dam sites and thus be measured up as to high risk and low risk of the possible construction sites.

The Bulkrivier Dam is small in infrastructure, as it does not consist of a water treatment plant, nor is it open to the public. The area is remote and can be described as untouched as the area is reserved.

20

21

22

23

24

25

Sandrivier Dam The Sandrivier Dam, originates from the Sandrivier, also known as Palmiet river. This medium sized Dam was first completed in 1906, by 1929 the wall was raised for extra capacity. The Sandrivier Dam has a standard gravity concrete wall construction with hard sandy shale as foundation. This Dam handles flooding with a mere overspill section from the wall- being sufficient for a Dam of this volume and capacity.

Sandrivier, has a maximum height of 26 meters and width of 153 meters. The Dam holds a volume of 18Â 000 m3.

This Dam is situated in a part of untouched nature where controlled permit holders may fish. These fishermen work on a strict barbless and catch and release policy.

This Dam, like the Bulkrivier Dam, does not have a big infrastructure and sends their water to Port Elizabeth for treatment.

26

27

28

29

30

31

32

33

34

35

36

37

Groendal Dam Groendal Dam, originates from the Kwazunga river. The Groendal Dam is situated situated near Uitenhage in the Eastern Cape and was first completed in 1934, in 1974, the gravity arch wall was strengthened.

According to the British dam society (NA: 2011),the general shape of a gravity ach Dam, provides good sta-bility against the forces a Dam faces, but given a bad foundation, this structure will be unsuccessful and a hazard. Especially with a Dam wall of the height and capacity of the Groendal Dam, this Dam has a wall height of 51 m and a crest length of 125 meters. This could therefore be seen as a large Dam, with a natural high danger factor. An ogee slipway reduces the pressure on the wall during times of heavy rains and floods.

Groendal has its own water treatment works; however, these treatment works are several kilometres away from the Dam itself. The Dam is situated on a privately owned reserve. This Dam is not open to the public at all and special permits and permissions are required to enter the area. There is however, a walking trail close by in the reserve, but this will not lead you to the Dam structure.

38

39

40

41

42

43

44

45

46

47

48

49

50

51

Lower Van Stadens Dam In the Nelson Mandela Metropole, there are two Dams named the Van Stadens Dam. This often raises confusion; the one however, is called the Lower Van Stadens- and the other the Upper Van Stadens Dam. This refers to its position in the river, whether upstream or downstream. The Dam concentrated on for this project was the Lower van Stadens Dam, which consists of an 18 meter Dam wall and a weir. This Dam was completed in 1929, and is situated in a picturesque gorge, accessible only by a walking trail. The walking trail mentioned does require permission and substantial fitness.

This medium sized Dam consists of a gravity concrete wall and makes use of an overspill section in case of overflow of the Dam. The Lower Van Stadens Dam is by far the smallest Dam visited during this project with a mere 6500 m3 on the Dam wall volume itself, the smallest Dam other than the Lower van Stadens Dam is the Bulk rivier Dam with 14700 m3 wall volume. However, one needs to take into account that there is another Dam originating from the same river. Two smaller Dams then, hold a good amount of water and do involve less risk, because of the size of the structure.

52

53

54

55

56

57

58

59

60

61

62

63

Kouga Dam The Kouga Dam, also known as the Paul Sauer Dam is situated near a small farm town in the Eastern Cape, named Patensie. This Dam was first completed in 1969, Gamtoos tourism website states (NA: 2008): “Provision was made in the design to allow for a future raising of the water 1ev by some 15.2 meters.”

Mr. Pierre Joubert, Chief executive officer of the Gamtoos Irrigation Board, stated that the development to strengthen the Dam wall would possibly commence in 2014 or 2015. Joubert also states: “The raising of the wall is just a possibility in the future. No decisions have been taken as yet” (Joubert: 2013).

The Paul Sauer Dam started the era of double curvature arch Dams in South Africa, and thus received an award in 1970, for outstanding engineering by the South African Institution of Civil Engineers.

The Kouga Dam provides water for irrigation; this canal is 97 km long and reaches the Loerie balancing Dam. This water is bought by farmers and forms a critical part of agricultural development in the Gamtoos Valley. This Dam also boasts with a small hydroelectricity plant, according to the Gamtoos tourism website, this plant is not yet economical but definitely a step in the right direction.

64

65

66

67

68

69

70

71

72

73

74

75

76

77

78

79

80

81

82

References: Joubert, P. 2013. Fotografie Projek. 28 October. Email to P. Joubert. [Online]. Available email: pierre.j@gamtooswater.co.za [28 October 2013].

Molden, D.,De Fraiture, C & Rijsberman, F. 2007. Water Scarcity- The Food Factor. 29 October [Online] Avaialble: EBSCOhost database Academic Search Premier, item: 25742937 [28 October 2013].

NA. 2008. Gamtoos Tourism- Kouga Dam. [Online]. Available:http://www.baviaans.net/index. php?page=page&menu_id=3&submenu_id=6 [30 October 2013].

NA. 2013. South African dams- Reservoirs in South Africa: Dam Construction. [Online]. Available: http://www. southafricandams.co.za/ [28 October 2013].

NA. 2011. The British Dam Society: Caring for dams, people and the environment. [Online]. Available: http:// www.britishDams.org/BDS_Leaflet_2012.pdf [30 October].

83