This collector is equipped for a maximum flow of 22.8 m3/s, has a total length of 18.3 km, set at an elevation of around 1550m.
At La Fouly, it captures the inflows of the upper Val Ferret and drains the waters of the Treutse-Bo, Planereuse, Saleina and Trient streams along its route.
- The tunnel leads to Esserts into a compensation basin holding useful capacity of 220,000m3 between elevations 1504m and 1516m.
- A reinforced shaft links the basin to the Châtelard-Vallorcine power plant.
- Water from the East Collector can be turbined directly onto the Les Esserts-Le Châtelard waterfall or pumped back into the Emosson reservoir.
Technical file
| Construction year | 1967-1973 |
| Put into operation | 1975 |
| Municipality | Orsières/Trient |
| Altitude | 1574m to 1516m. |
| Max flow | 27m³/sec |
