Cmc in Algeria: the transfer tunnel and the Tabellout dam

Work is in progress in Algeria on the Cmc site to construct the Tabellout dam and transfer tunnel.

The works involve a number of different sites, the dam is 30km to the south of Jijel, at the point where the rivers Djen Djen and Rha converge, flanked by the RN77 state highway which will have to be deviated because it is below the maximum flood level, and the area in which the TBM will enter the tunnel to be excavated in the direction of the dam, situated 40km from the dam and 80km from Setif.

The construction works are part of the eastern system of the Setif-Hodna project whose aim is to provide drinking water and irrigation to the El Eulma region by drawing water from the Tabellout dam, transferring this by pumping in a north-south direction to a holding facility known as Draa Diss, about 40km as the crow flies.

The volume of water to be transferred amounts to 189 million m3/per annum, 20% of which will be drinking water, the remaining 80% to be used for irrigation. The surface area of the hillside reservoir is 402km2 with a total storage capacity of 294 million m3, 214 million of which can be used.

The Tabellout dam is constructed in RCC with a volume of 975,400 m3, the height from foundations to crest is 121 metres, and at its crest it is 366 metres long and 8 metres wide.

The linking tunnel starts from the lift station that draws water from the Tabellout dam reservoir and then pumps it to up the height of the tunnel entry where gravity sends it flowing down the tunnel to the buffer pool on the river Halib from where a second pumping station delivers it to the Draa Diss holding facility.

Cmc in Algeria: the transfer tunnel and the Tabellout dam