Capacity share
6.6%
A smaller dam, but every percentage point still counts during tight supply.
Individual dam profile
Wemmershoek
Wemmershoek is currently at 88.8%, holding 52.2 of its 58.8 gigalitres of capacity. That is 1.1% below the same week last year (89.9%). Against the same-week long-run average, it sits 3.4% above. Relative to 2017's drought benchmark week, it is 45.2% higher.
88.8% full · Updated 14 Sept 2026 52.2 / 58.8 GL
Role in the system
Wemmershoek makes up 6.6% of total system capacity and currently holds 7.8% of the stored water — fuller than the system as a whole.
Share of stored water
7.8%
Roughly in line with its share of total capacity.
Location
In the Hawequa / Wemmershoek mountains between Franschhoek and Paarl.
Wemmershoek in the Western Cape supply system
Big Six dams shown; Wemmershoek highlighted.
Outer ring = total capacity · Filled area = current level
Background and reference facts
Wemmershoek is one of the older mountain dams in the Cape Town system, built in the 1950s after decades of planning around the valley's water-supply potential.
Long planning tail
Studied since the 1880s
Hydrographic surveys flagged the valley for water supply long before the dam was eventually built, making Wemmershoek a story of very long-term municipal planning.
Sources: Wikipedia
City project
Built for Cape Town
The dam was constructed specifically on behalf of the City of Cape Town, reflecting the era when municipal augmentation projects were the main answer to growing demand.
Sources: Wikipedia
System share
Smaller but strategic
Wikipedia pegs Wemmershoek at roughly 6.5% of WCWSS storage capacity — not dominant, but still meaningful in dry years.
Sources: Wikipedia
Storage trend and same-week benchmarks
Wemmershoek is tracking above the long-run average for this time of year. It sits 1.1% below the same week last year.
Weekly trend (last 2 years)
Currently 7.1% above the same week last year and 18.5% above the long-run average.
Same-week comparison by year
At 98.1%, this week sits 54.5% above the 2017 drought benchmark.
Recent weekly readings
| Date | Level | Storage | Weekly change |
|---|---|---|---|
| 11 Aug 2026 | 98.1% | 57.5 GL | -0.9 |
| 03 Aug 2026 | 99.3% | 58.2 GL | -0.7 |
| 27 Jul 2026 | 100.0% | 58.6 GL | +0.1 |
| 20 Jul 2026 | 99.9% | 58.5 GL | +0.0 |
| 13 Jul 2026 | 99.9% | 58.5 GL | +0.0 |
| 06 Jul 2026 | 99.9% | 58.5 GL | -0.1 |
| 29 Jun 2026 | 100.0% | 58.6 GL | +0.1 |
| 22 Jun 2026 | 99.9% | 58.5 GL | +0.4 |
| 15 Jun 2026 | 99.5% | 58.3 GL | +1.7 |
| 08 Jun 2026 | 97.8% | 57.3 GL | +1.1 |
| 01 Jun 2026 | 96.7% | 56.7 GL | +1.4 |
| 25 May 2026 | 95.3% | 55.8 GL | +2.5 |