Ferry Hamnavoe sails on the 'Short-sea Route' to Orkney during summer months ... for the first time in living memory
25th June 2017
The 8,780 tonne ferry Hamnavoe, which normally plies directly 28 miles from Scrabster in Caithness to Stromness, Orkney, sailed over the weekend on the Pentland Firth's 'Short Sea Route'. It is the seaway that is used on a daily basis by her 'rival' ship Pentalina.
It was all because of strong un-seasonal Westerly gales that swept over the North 'half' of Scotland, causing several West Coast ferry services to be cancelled.
The 112 metre Hamnavoe sailed on a 'roundabout' route to Stromness to 'escape' the worst of the sea-conditions when she left Scrabster at 14:20 on Saturday afternoon; putting in a crossing to the Orkney port that took her well over two hours and involved nearly double her normal mileage. A strong West-flowing 'spring tide' ebb-stream was running through the Pentland Firth at the time.
From Scrabster, Hamnavoe sailed parallel to the Caithness coast for nearly 20 miles including a transit of the Pentland Firth's Inner Sound that took her within one mile of Gills Harbour ... Pentalina's Caithness terminal.
On Saturday afternoon, when Hamnavoe was in a position just East of Stroma island, the big ferry turned Northwards and entered Scapa Flow via Hoxa Sound; the seaway followed by 2,382-tonne Pentalina on her daily multiple crossings from Gills Bay to St Margaret's Hope.
From there, Hamnavoe set her course North Westwards to Stromness, arriving there around 16:40.
The Stromness-based ship's unusual voyage through to Inner Sound ... between Gills Bay and the isles Stroma ... was spotted from the North Coast by at least four members of Gills Harbour Ltd, who are alert to 'out of the ordinary' sea occurrences in the Eastern Pentland Firth.
It is thought to be the first occasion during the Summer months that a Scrabster-terminus Orkney-bound vessel had used the Firth's 'Short Sea route' since the normal direct sailings to Stromness was introduced in 1945: in earlier years the trans-Pentland service used to terminate at Scapa Pier, near Orkney's Kirkwall Crown Post Office, as a small Royal Mail subsidy was paid then.
Direct sailings to the West of Hoy ... with views of mighty St John's Head and the Old Man of Hoy sea-stack ... commenced after a decision was taken in 1945 to re-route 'First Class' post by air to Kirkwall.
The 'secret' to Saturday afternoon's unusual outward bound trip from Scrabster lies in the ebb-tide phenomenon The Merry Men of Mey, the ferocious tidal race ... known locally and to mariners as a 'roost'.
It spans the entire width of the Pentland Firth from just West of Caithness's St John's Point .. c. 1.5 miles West of Gills Harbour ... to off Torness, the SW tip of the island of Hoy, during the twice-daily 6.5 hourly ebb-tide cycle.
With the powerful West-flowing ebb opposing a Westerly gale ... which peaked at over 40 mph during the afternoon ... the roost's multi-directional breaking waves were approaching winter levels, when up to 10 metre-high breakers there are 'commonplace'.
But, as is pointed out in the notes accompanying navigational Admiralty Charts for the Pentland Firth, during such conditions The Merry Men of Mey acts to absorb incoming swells from the Atlantic Ocean. Those were driven by the atmospheric 'deep depression' ... large area of low air pressure ... that moved slowly eastwards over the weekend of 24/25.06.2107, bringing the 'disturbed' weather in its wake over the the Scottish Highlands & Islands.
The Merry Men of Mey ... where white-water breaking waves are seen on a year-round basis ... acts as a kind of 'floating breakwater', calming to near-zero the sea-surface disturbance to the East of the roost, as was the case on Saturday afternoon
This was only the third recorded occasion during the present decade that Hamnavoe has used the Inner Sound and the 'Short Sea Route', both previously were during winter; once in January 2012 and again during February, 2016.
When heavy incoming Atlantic Ocean-origin Westerly swells are rolling into the Pentland Firth, Hamnavoe diverts from her usual direct route for around 30 trips per annum, but that is usually via Cantick Sound and then through the sheltered waters of Scapa Flow.
She used this 'regular diversion' seaway on her late evening return trip from Scrabster on Saturday 24th ... and again on both legs of her return morning crossings of Sunday 25th June, 2017.
The use of the Short-sea Route on Saturday afternoon prevented the risk of a potential cancellation at a busy time of the year, whilst it also ensured a smoother voyage for her on-board passengers.
Hamnavoe managed to complete all three scheduled return trips on Saturday. Her operators SERCO NorthLink Ferries had given advance warnings that there could be some delays due to actual and forecast weather conditions.
Pentalina does four return trip on summer Saturdays and all were completed as planned on June 24th.
Westerly gales in late June are very uncommon in the Far North of Scotland, but not unknown. One is 1897 caused a loss of life amongst small-boat fishermen off the North Sutherland coast.
PHOTO by Mr Mark Gibson of MV Hamnavoe passing though the Pentland Firth's Inner Sound on Saturday afternoon 24.06.17. The photo is from near (to the East of) John O'Groats in foreground with Stroma island in the background.