Transmed

This 2,200 km gas pipeline links Northern Italy to one of the world's biggest natural gas reservoirs, located in the algerian desert. The project presented many technological challenges:  the most important was the laying of the subsea pipeline in the Sicily Channel at a depth of more than 600 meters.
Construction of the first pipeline was completed in 1983. The doubling of the pipeline was realized in 1997.

Algeria has one of the largest natural gas reservoirs in the world at Hassi R'Mel. It was discovered in 1955 and has proven reserves of around 2,000 billion cubic meters of recoverable natural gas.
In 1972 Eni signed the first agreements to import gas into Italy with Sonatrach, the Algerian state authority that manages all the activities related to natural gas once Algeria obtained its independence. The final contract with Eni was signed in 1977 after details had been settled with Tunisia governing the construction of the gas pipeline across its territory and its operation. A flow of 12.3 billion cubic meters was set for a period of 25 years.
Construction of the first line, named Transmed was completed in 1983. At the end of 1990 Eni signed another agreement with Sonatrach for the importation of another 7 billion cubic meters per year. To handle this extra volume, a second line was built.

A 550 km long pipeline carries the gas from the Hassi R'Mel reservoir in Algeria up to the border with Tunisia where it is fed into the Transmed line. The arrival point in Italy is Minerbio, near Bologna in the Po Valley, where the gas enters the national gas distribution system.
The line is 2,220 km long of which 370 km is in Tunisia with a diameter of 1,200 mm, 380 km is on the seabed with a diameter of 650 mm, and 1,470 km in Italy with a diameter of 1,200 mm. The new line runs mostly parallel to the existing gas line.

The six compression stations built for the first Transmed line have been expanded and revamped so that only 2 new stations have had to be built.
The construction of the new Transmed called for 1,100,000 tons of steel and along its course the pipeline had to cross 850 rivers or streams, 67 railway lines, 181 roads or highways and 1,640 provincial roads. In the course of the six years required to build the new pipeline, more than 40 construction sites were opened employing over 2,500 men.