Australia's Largest Dam: Gordon Dam, Tasmania
Gordon Dam** on the **Gordon River** in **southwestern Tasmania** is **Australia's largest dam by storage capacity** and one of its tallest arch dams.
Key Specifications
| Parameter | Value |
| Type | Double-curvature concrete arch dam |
| Height (crest) | 140 m (459 ft) |
| Crest Length | 198 m (650 ft) |
| Base Width | 18 m (59 ft) |
| Reservoir | Lake Gordon |
| Gross Capacity | 12,492,934 ML (12.5 km³ / 9.95 million acre-ft) |
| Active Capacity | 11,316,000 ML |
| Catchment Area | 1,280 km² |
| Power Station | Gordon Power Station (432 MW, 3 × 144 MW Francis turbines) |
| Annual Generation | ~1,800 GWh (~13% of Tasmania's electricity) |
| Construction | 1974–1978 (Hydro-Electric Commission) |
Why It's the Largest
- Storage volume exceeds all other Australian dams (next: **Lake Eucumbene / Eucumbene Dam**, Snowy Scheme — 4,798,000 ML).
- Height is 2nd after **Tumut Pond Dam** (161 m, Snowy Mountains) but Gordon's *arch* form in a narrow gorge is more dramatic.
Engineering Significance
- **Double curvature** (arch + crown cantilever) transfers load to abutments — efficient for narrow gorges.
- **Construction innovation:** Cableway placement, pre-cooled concrete (ice), grout curtain 120 m deep.
- **Seismic design:** Tasmania is low-seismicity; but dam meets modern criteria.
Environmental Controversy
Gordon Dam was the **flashpoint of Australia's first major environmental campaign** — the **Franklin River dispute (1979–83)**. The proposed **Franklin-below-Gordon Dam** would have flooded the Franklin River wilderness. **High Court (1983)** upheld federal World Heritage legislation, stopping it. Gordon Dam itself flooded Lake Pedder (1972) — earlier controversy.
Tourism & Access
- Location: 2.5 hrs drive from Hobart via Lyell Highway (A10).
- Viewing: Dam wall walkway (guided tours summer), Gordon River Rd lookout.
- Gordon River Cruises: From Strahan (West Coast) — traverse Lake Gordon, enter **Gordon River** (World Heritage wilderness).
- Pedder Wilderness Lodge (nearby) — accommodation.
Other Notable Australian Dams
- Eucumbene Dam (Snowy) — largest *mainland* storage.
- Tumut Pond Dam — highest (161 m).
- Warragamba Dam (Sydney) — largest *urban supply* (2,031,000 ML).
- Ord River Dam (Lake Argyle) — largest *tropical* storage (10,760,000 ML).
Gordon Dam is a **monument of mid-century hydro-industrial ambition** — now operating within a World Heritage Area that almost wasn't. Its waters power Tasmania's clean grid while the Franklin runs free beside it.