Sustainable Resource Management: WESTERN CAPE WATER SITUATION | JANUARY 2012
Situation as at 30 January 2012
| Dam | Capacity | 01-Dec-11 | 30-Jan-12 | Decrease (-) from 1 Dec '11 | ||
| Storage | % | Storage | % | Mcm | ||
| Steenbras Upper | 31.7 | 31 | 98 | 30 | 95 | 1 |
| Steenbras Lower |
33.5 | 27 | 80 | 21 | 63 | 6 |
| Wemmershoek | 58.6 | 46 | 79 | 42 | 72 | 4 |
| Voëlvlei | 165.4 | 140 | 84 | 108 | 65 | 32 |
| Theewaterskloof | 480.2 | 389 | 81 | 317 | 66 | 72 |
| Berg River Dam | 130 | 123 | 95 | 103 | 79 | 20 |
| Total including BRD | 899.4 | 755 | 84 | 621 | 69 | 134 |
No rainfall was recorded in the catchment areas of the Wemmershoek and Voelvlei Dams during the last week. Rainfall recorded in the Theewaterskloof and Steenbras Dams' catchment areas was 2.7mm and 3.9mm respectively. The gross system storage has decreased from 642 million m3 to 621 million m3 (69%). The total decrease since the 1st Dec 2011 is 134 million m3.
According to the South African Weather Service (SAWS) there is a slight chance of rainfall (<5mm) in the Eastern Areas such as Riversdale on Wednesday. At present the Norwegian Meteorological Institute (NMI) forecast slightly more widespread rainfall in areas such as Robertson, Grabouw and Hermanus. There may also be a chance of rainfall next Monday.
Situation as at 23 January 2012
| Dam | Capacity | 01-Dec-11 | 23-Jan-12 | Decrease (-) from 1 Dec '11 | ||
| Storage | % | Storage | % | Mcm | ||
| Steenbras Upper | 31.7 | 31 | 98 | 30 | 95 | 1 |
| Steenbras Lower |
33.5 | 27 | 80 | 22 | 66 | 5 |
| Wemmershoek | 58.6 | 46 | 79 | 43 | 73 | 3 |
| Voëlvlei | 165.4 | 140 | 84 | 113 | 68 | 27 |
| Theewaterskloof | 480.2 | 389 | 81 | 327 | 68 | 62 |
| Berg River Dam | 130 | 123 | 95 | 107 | 82 | 16 |
| Total including BRD | 899.4 | 755 | 84 | 642 | 71 | 113 |
No rainfall was recorded in the catchment areas of the Theewaterskloof, Wemmershoek and Voelvlei Dams during the last week. Rainfall recorded in the Steenbras and Berg River Dams' catchment areas was 0.5mm and 3mm respectively.
However, right nearby in De Doorns, the hot humid conditions of last week resulted in a severe, localized thundershower. According to the SABC report on the web:
"Farmers in the area have also claimed extensive flooding and hail damage to some of the vineyards. Disaster management spokesperson, Theo Botha says: "The N1 will be closed for a considerable time. Traffic is currently being diverted around the Ceres area. At the moment we cannot say how long the road will be closed but 30 - 40 meters section in both directions has washed away…"
The gross system storage has decreased from 658 million m3 to 642 million m3 (71%). The total decrease since the 1st Dec 2011 is 113 million m3.
According to the South African Weather Service (SAWS) there is a good (60% probability) of showers of about 5mm throughout the South Western Cape Region (Cape Town, Malmesbury, Robertson, Riversdale) on Monday 23 Jan 2011. According to the Norwegian Meteorological Institute (NMI) the showers may persist in Riversdale on Tuesday but after that negligible rainfall is expected until possibly next Monday/Tuesday (30/31 Jan 2011).
Situation as at 16 January 2012
| Dam | Capacity | 01-Dec-11 | 16-Jan-12 | Decrease (-) from 1 Dec '11 | ||
| Storage | % | Storage | % | Mcm | ||
| Steenbras Upper | 31.7 | 31 | 98 | 30 | 95 | 1 |
| Steenbras Lower |
33.5 | 27 | 80 | 22 | 66 | 5 |
| Wemmershoek | 58.6 | 46 | 79 | 43 | 73 | 3 |
| Voëlvlei | 165.4 | 140 | 84 | 118 | 71 | 22 |
| Theewaterskloof | 480.2 | 389 | 81 | 336 | 70 | 53 |
| Berg River Dam | 130 | 123 | 95 | 109 | 84 | 14 |
| Total including BRD | 899.4 | 755 | 84 | 658 | 73 | 97 |
No rainfall was recorded in the catchment areas of the Theewaterskloof, and Voelvlei Dams during the last week. Rainfall recorded in the Berg River, Steenbras and Wemmershoek Dams' catchment areas was 2mm, 2.3mm and 2.5mm respectively. The gross system storage has decreased from 677 million m3 to 658 million m3 (73%). The total decrease since the 1st Dec 2011 is 97 million m3.
The South African Weather Service (SAWS) forecast negligible rainfall for the coming week, with only South Eastern areas such as Riversdale having a 30% chance of < 5mm rainfall. The Norwegian Meteorological Institute also generally forecast negligible rainfall. Less than 2mm is forecast for the Southern and Eastern areas (Hermanus, Robertson and Riversdale) with slightly more at Riversdale on Friday/Saturday.
Situation as at 09 January 2012
| Dam | Capacity | 01-Dec-11 | 09-Jan-12 | Decrease (-) from 1 Dec '11 | ||
| Storage | % | Storage | % | Mcm | ||
| Steenbras Upper | 31.7 | 31 | 98 | 30 | 95 | 1 |
| Steenbras Lower |
33.5 | 27 | 80 | 23 | 69 | 4 |
| Wemmershoek | 58.6 | 46 | 79 | 44 | 75 | 2 |
| Voëlvlei | 165.4 | 140 | 84 | 121 | 73 | 19 |
| Theewaterskloof | 480.2 | 389 | 81 | 346 | 72 | 43 |
| Berg River Dam | 130 | 123 | 95 | 113 | 87 | 10 |
| Total including BRD | 899.4 | 755 | 84 | 677 | 75 | 78 |
No rainfall was recorded in the catchment areas of the Theewaterskloof, Steenbras, Wemmershoek and Voelvlei Dams during the last week. The gross system storage has decreased from 695 million m3 to 677 million m3 (75%). The total decrease since the 1st Dec 2011 is 78 million m3.
According to SAWS and the NMI there is a slight chance of rainfall on Friday (13th January). SAWS forecast a 30% chance of about 4mm, while the NMI intensities vary from 1 to 10mm, with the lighter estimates in the South Eastern areas (Riversdale, Robertson).
