Dam · North West · South Africa · DWS
Kosterrivier Dam
100.8% full
Total capacity
12.42 Mm³
River
Koster River
Basin
Unknown
Primary use
water supply
Operator
DWS South Africa
Coordinates
-25.700°S, 26.904°E
Last updated
2026-10-05
Current fill
100.8%vs 7 days ago
0.0%stable
vs 1 year ago
N/A7-day trend
→stable
Drought context
Rain over the last three months · 21 September 2026
Moderately wet
In the three months to 21 September 2026 the area around Kosterrivier Dam had more rain than normal for the season. Rainfall compared with the long-run record for the same season at this point (Copernicus Global Drought Observatory, SPI-3 index +1.42). Rain, not storage. South Africa drought figures →
Weekly storage
Fill history — multi-year
About this dam
Data source
official
Storage data: Department of Water and Sanitation (DWS) Weekly State of Dams report, South Africa.
Catchment Weather
Past 30 days + 14-day forecast · Open-Meteo
About Kosterrivier Dam
As of October 5, 2026, Kosterrivier Dam is filled to 100.8% of its total capacity, holding roughly 13 Mm³ of water out of a maximum 12 Mm³. At this level the reservoir is effectively full.
Over the most recent week on record the fill level has held broadly steady (+0.0 pts).
Across the readings we hold for Kosterrivier Dam — 17 data points between May 31, 2026 and October 5, 2026 — the level has ranged from a low of 100.6% (August 31, 2026) to a high of 102.9% (May 31, 2026). On average the reservoir is fullest around May and at its lowest around August.
It is operated by DWS South Africa primarily for water supply. It lies within the Unknown basin at 25.700°S, 26.904°E.
Key facts
- Current fill level
- 100.8%
- Water stored
- 13 Mm³
- Total capacity
- 12 Mm³
- 7-day change
- No change
- Primary use
- Water supply
- River
- Koster River
- River basin
- Unknown
- Operator
- DWS South Africa
- Coordinates
- 25.700°S, 26.904°E
- Last updated
- October 5, 2026
Recent readings
| Date | Fill level | Volume (Mm³) |
|---|---|---|
| 5 Oct 2026 | 100.8% | 13 |
| 28 Sep 2026 | 100.8% | 13 |
| 21 Sep 2026 | 100.8% | 13 |
| 31 Aug 2026 | 100.6% | 13 |
| 24 Aug 2026 | 100.8% | 13 |
| 17 Aug 2026 | 100.8% | 13 |
| 10 Aug 2026 | 100.8% | 13 |
| 3 Aug 2026 | 100.8% | 13 |
| 27 Jul 2026 | 100.8% | 13 |
| 29 Jun 2026 | 100.8% | 13 |
| 22 Jun 2026 | 100.8% | 13 |
| 16 Jun 2026 | 100.8% | 13 |
Nearby reservoirs
See also: South Africa dam levels, explained — how the DWS Weekly State of Dams report becomes the national and provincial figures.