High Island Reservoir
New Territories · New Territories · New Territories catchments
Capacity
281.11 hm³
Coordinates
22.375°N, 114.355°E
Operator
Water Supplies Department (WSD)
83.6% full
Current fill
83.6%vs 7 days ago
0.0%stable
vs 1 year ago
-0.5%year-over-year
7-day trend
→stable
Drought context
Storage vs October average
110%of normal
83.6% full on 2026-10-01, against an average of 75.9% for October across 8 years of readings (+7.7 points).
Rain over the last three months · 21 September 2026
Near normal
In the three months to 21 September 2026 the area around High Island Reservoir had rain close to 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 +0.38). Rain, not storage. Hong Kong drought figures →
Catchment Weather
Past 30 days + 14-day forecast · Open-Meteo
Technical specifications
| Total capacity | 281.11 hm³ |
| Usable capacity | 281.11 hm³ |
| Year built | 1978 |
| Primary use | water supply |
| Operator | Water Supplies Department (WSD) |
| Province | New Territories |
| Autonomous community | New Territories |
| River basin | New Territories catchments |
Satellite imagery: Esri, Maxar, Earthstar Geographics. 22.375, 114.355 · Open in Google Maps
About High Island Reservoir
As of October 1, 2026, High Island Reservoir is filled to 83.6% of its total capacity, holding roughly 235 hm³ of water out of a maximum 281 hm³. At this level the reservoir is high.
Over the most recent week on record the fill level has held broadly steady (+0.0 pts), and it sits close to where it was a year earlier.
Across the readings we hold for High Island Reservoir — 184 data points between January 16, 2019 and October 1, 2026 — the level has ranged from a low of 51.5% (May 1, 2022) to a high of 84.8% (September 16, 2019). On average the reservoir is fullest around October and at its lowest around April.
The dam at High Island Reservoir was completed in 1978. It is operated by Water Supplies Department (WSD) primarily for water supply. It lies within the New Territories catchments basin at 22.375°N, 114.355°E.
Key facts
- Current fill level
- 83.6%
- Water stored
- 235 hm³
- Total capacity
- 281 hm³
- 7-day change
- No change
- Year-on-year
- ▼ 0.5 pts
- Primary use
- Water supply
- River basin
- New Territories catchments
- Year completed
- 1978
- Operator
- Water Supplies Department (WSD)
- Coordinates
- 22.375°N, 114.355°E
- Last updated
- October 1, 2026
Recent readings
| Date | Fill level | Volume (hm³) |
|---|---|---|
| 1 Oct 2026 | 83.6% | 235 |
| 16 Sep 2026 | 84.0% | 236 |
| 1 Sep 2026 | 83.4% | 234 |
| 16 Aug 2026 | 81.8% | 230 |
| 1 Aug 2026 | 77.7% | 218 |
| 16 Jul 2026 | 71.6% | 201 |
| 1 Jul 2026 | 67.8% | 191 |
| 16 Jun 2026 | 65.0% | 183 |
| 1 Jun 2026 | 62.4% | 176 |
| 16 May 2026 | 62.8% | 176 |
| 1 May 2026 | 63.9% | 180 |
| 16 Apr 2026 | 64.9% | 182 |