AN IMPRESSIVE PROJECT
This hydraulic dam, the fifth largest in the country by its storage capacity of around 294 million cubic metres, is situated in the wilaya of Jijel, along the east coast of the country, just over 350 kilometres from Algiers.
As an important link in the system for the transfer of water to the tableland, the dam consists of a million cubic metres of roller-compacted concrete. With a height of 115 metres, a crest length of 392 metres and a crest with of 8 metres, it comes with a stepped open channel spillway 60 metres wide and two temporary diversion galleries each 6 metres in diameter and 400 metres long.
USE OF A TUNNEL BORER
The contract also includes the construction of a transfer gallery 13 kilometres long and 4 metres in diameter. This will be made entirely with a tunnel borer driving through different geological formations. Tunnelling will start from an isolated spot roughly 30 kilometres from the site of the dam itself and work its way right up to the dam. The segments will also be prefabricated on site at the entrance to the tunnel.
