Peti dam
The Peti dam, a concrete arch 46 m high with an 85 m crest on the Santa Bárbara river, about a hundred kilometres from Belo Horizonte, has fed a 9.4 MW plant since 1946. Its operator monitors expansive-reaction damage in the concrete. Since the September 2022 baseline (4,052 crack traces, 2,023 m in total), we have photographed the downstream face every year at less than a millimetre per pixel, registered the orthophotos on the same benchmarks and recorded new or lengthened cracks: 22 in 2023, 4 in 2024, 6 in 2025. The fourth campaign took place from 22 to 24 September 2025.
Key facts
| Structure | Concrete arch dam in service since 1946: 46 m high, 85 m crest, six 6 × 5 m gates, 43.578 hm³ reservoir over 6.78 km², 9.4 MW plant with two units |
|---|---|
| Campaigns | 26–30 Sept 2022 (baseline), 12–15 Sept 2023, 26–28 Aug 2024, 22–24 Sept 2025 |
| Method | GNSS base on a dam benchmark, flights 5–6.5 m from the faces, face orthophotos on an identical cylindrical projection every year |
| Face resolution | Downstream face: 0.7 to 0.9 mm per pixel; upstream face: 1.2 mm in 2025 |
| 2022 baseline | 4,052 crack traces, 2,023 m in total, 1,400 detailed photos |
| Evolution | 22 new or lengthened cracks in 2023, 4 new in 2024, 6 in 2025: downstream-face stability confirmed |
| 2025 campaign | 2,037 photos, 21 flights, 12.7 km flown, 7 orthophotos (3.9 gigapixels), 68 comparison plates |
| Missions listed | 3 |
On the map
3 missions at this location
Fourth campaign on the Peti dam
From 22 to 24 September 2025: 2,037 photos in 21 flights and 12.7 km flown, 7 orthophotos totalling 3.9 gigapixels, 71 plates including 68 comparison plates; six new or longer cracks since 2024, downstream-face stability confirmed since the 2022 baseline.
- 2 037 photos
- 6 new cracks
Third campaign on the Peti dam
From 26 to 28 August 2024: 1,610 photos of the downstream face and 832 of the upstream face from 5 m away, 2023 and 2024 campaigns registered on the 2022 reference; four new cracks, cumulative length almost unchanged.
- 4 new cracks
Second annual campaign on the Peti dam
From 12 to 15 September 2023: 1,649 photos of the faces from 6.5 m away, face orthophotos registered on the 2022 baseline (4,052 cracks); 22 new or longer cracks and 54 more visible ones recorded.
- 22 new cracks
- 0,8 mm per pixel
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97310 Kourou
French Guiana
Route des Trois-Îlets
97229 Les Trois-Îlets
Martinique
20030-041 Rio de Janeiro – RJ
Brazil