Kahramaa (Qatar general Electricity & Water Corporation) had appointed Prysmian Cavi è Sistemi Energia SrL for a power transimission system expansion project, which was to develop the country's first ever submarine power link serving Qatar.

The project in general required the engineering, construction, installation and commissioning services for high and extra high voltage underground and underwater power cables  for a total of 131km of 220kV and 77km of 132kV cables and other relative products.

The contract between Prysmian and Assodivers involved the installation and protection of six underwater cables accross the Doha's port. Each cable was installed on parallel route of each other and had a continous total length of 6.2km.

As the project was executed in two campaigns on 2010 and 2011 respectively, each campaign was representing a circuit of three cables each. In addition, two FO cables were attached with a power cable on the central route of each circuit.

The power and optical cables were produced in Prysmian factory at Arco Felice, Italy. The six cable lengths were loaded on the cable laying barge 'Atalanti' and transported to Doha. The vessel was also used for the cable laying, since with its low draft it could pass all over the laying route.

Conduits were present at both landing areas, through which the cables were pulled during the landing activity; polyethylene pipelines, about 150 m long, were preinstalled at West Bay shore, while at Ras Abu Aboud shore end 50 m long pipes were preinstalled in trenches.

At sea the cables were buried to a target burial depth (coverage depth) of 1.0 m, using either 'AssoTrencher VIII' trenching vehicle or 'AssoJet II' jetting vehicle, depending on the soil features. Further additional protection by mattresses was also implemented on specific crossings with other services.

Project Specifications

Kahramaa Project - Phase 2

Year:
2011
Contractor:
Prysmian Cavi è Sistemi Energia SrL
Cable Type:
Power 3x220KV XLP AC & 1 FO bundled
Cable Weight:
Power: 60.45kg/m FO: 3.4kg/m
Cable Diameter:
146.9mm
Service Provided:
Cable Transportation - Installation - Protection
Laying Length:
21,000m
Owner:
KAHRAMAA
Trenching Length & Cover Depth:
13,200m @ 1.0m
Jetting Length & Cover Depth:
8,530m @ 1.0m
Alternative Protection:
Mattresses: 160m
Location:
Doha Bay, Qatar
Max Water Depth:
12m