TRAC were engaged to install two new beacons on isolated rocks in the Sound of Harris to ensure the continued safe passage of shipping through the Strait.
The Sound of Harris provides the main sea passage through the Outer Hebrides from the Atlantic Ocean to the Minch. There are many islands and numerous rocks and skerries in this stretch of water making it potentially treacherous to shipping. As well as merchant and recreational shipping passing through there is a regular daily ferry from Harris to Berneray. The Northern Lighthouse Board must ensure its Aids to Navigation; beacons, lights etc. are suitably positioned and functioning to allow safe passage for all mariners. Recent surveys had highlighted two such waymark beacons were in need of renewal.
TRAC engaged the assistance of a work-boat operator to provide the transport for materials and personnel to the marine sites.
TRAC’s team were deployed to carry out the following work items to suit tides, sea state and weather conditions:
- Clear rocks of seaweed, break out and level areas to receive new beacons
- Drill 60mm holes to a depth of 1.5 metres
- Grout in holding down bolts
- Position new 5 metre stainless steel beacons in situ
- Post tension all bolts
- Install GRP day-mark sleeves and top marks
- Remove and dispose of existing beacons
Works completed in a realistic timeframe, within budget. No accidents on site, no disruption to shipping and no damage to sites that are within a National Scenic Area and Marine Special Protection Area.