L’Anse au Diable & Dowden’s Point Electrode Sites
southern labrador & conception bay south, newfoundland & labrador
|CLIENT:||Labrador-Island Link Limited Partnership|
|CONTRACT TYPE:||Unit Price|
|Project SIZE:||Total rock required approx. 300,000 tonnes|
H.J. O’Connell (HJO), a division of Bird, has completed the contract to supply and construct shoreline electrodes at L’Anse au Diable in Labrador, and Dowden’s Point in Newfoundland. Each electrode site location will be connected to a converter station at Muskrat Falls and Soldiers Pond respectively, as part of the Muskrat Falls hydroelectric project. The electrode sites are high-capacity grounding systems that are installed at each end of a high voltage direct current (HVdc) transmission system.
HJO completed the civil and marine portion of the electrode sites on time and on budget. Each electrode system was comprised of 80 perforated HDPE wells (approximately 15 m long) placed vertically, to accept electrode element rods and buried in porous rocks of a breakwater for protection against ice and ocean waves. Major components of the civil scope included rock drilling, blasting and hauling over 150,000 t of rock materials to each electrode location, construction of access roads, 80 electrode wells, buried cable duct banks, pull boxes, trenches and junction boxes.
Each electrode location involved the construction of the breakwater structure, which required approximately 90,000 t of core material, 10,000 t of filter and 50,000 t of six to eight ton armour stone in the Atlantic Ocean, in water depths up to six metres.