19 Jun 2012
71 days after drilling started, the island of Shapinsay has a 2km long, 180mm diameter, subsea pipeline connection to mainland Orkney.
Until now, the water supply for Shapinsay’s population of 300 has been from a basic treatment works drawing water from the island’s five boreholes. Problems associated with the basic nature of the treatment works along with the limited amount of water available from the boreholes will soon be in the past and when the project is completed, the island will have a direct water supply from mainland Orkney.
Working from the mainland, the first 350m of the record-breaking drill was undertaken on a radius to a depth of 50m, followed by 1200m of horizontal drilling through rock, approximately 20m below the seabed. Further radius drilling realigned the bore back up for the final ‘punch-out’ on Shapinsay. The 2000m length SDR6, 180mm diameter HPPE pipeline, which had be strung-out, butt-welded, pressure tested and positioned on rollers on the Shapinsay side, was then pulled back through the bore.
Work is continuing with the construction of a new pumping station on the mainland and pipelines on Shapinsay, together with tie-in work at the existing plant before the new supply is finally commissioned and put into service later this year.
Installed by Directional Drilling, it is the longest land-to-land, subsea, utility pipeline in the UK.