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UK—Channel Islands No 7 submarine cable system

In 1986 there was a visit to the Stoke Fleming telephone exchange for the Doomsday Reloaded project.  This is probably the old telephone exchange in Mill Road, which is now a cold store for a fish merchant.

    Just outside Stoke Fleming is a    
 large building looking like a stone   
 walled bungalow.Actually it is the    
 telephone exchange. It has been built 
 to blend in with its beautiful area.  
    It is very big because it is not   
 just the village's phone lines which  
 go there. From Blackpool Sands a cable
 goes under the sea to the Channel     
 Islands.  It can carry 500 telephone  
 calls at once.                        
   In our visit to the Exchange we saw 
 where it joins the national phone     
 system. In the exchange they have     
 their own enormous generators to keep 
 the phones working if there is a cut  
 in the electricity supply.            
    The exchange is automatic and we   
 watched the numbers being dialled.

Poldhu Cable Landing for TAT-9

The TAT-9 cable entered service in 1992 and was retired in 2004.

It is understood that at least a section of the cable near the coast has been recovered from the seabed to reduce the hazard to vessels which fish the area.  It is not known what length was recovered.  Further information

Modern maps have not been found which show the route of the cable, but a mariners chart dated 2003 (prior to the decommissioning)  shows the landing point on the south side of Poldhu beach near Mullion in Cornwall.

The map below is further confirmation of the TAT-9 landing point (taken from this document).

Information on the internet generally confirms that the cable landing station for TAT-9 was Goonhilly.

There is interest in the reuse of the remaining portions of the TAT-9 cable for ocean monitoring. Further information and significant technical details of the cable and its repeaters can be found in this review pdf.

Isles of Scilly 33kV Cable Exposed (Due for Replacement)

Isles of Scilly 33kV Undersea Cable

Due for replacement sometime after 2015, the existing 33kV undersea cable to the Isles of Scilly from the mainland has been exposed by the 2013/14 winter storms.

The 55km cable installed in 1988 as part of a project to reinforce the supply to the islands, and to interconnect the outer islands, is at the end of its economic life.

The cable has a capacity of 7.5MW (maximum demand is currently approximately 4.5MW on the islands), and can be used to backfeed to the mainland 4MW if required from the 5.7MW primarily from the power station at St Mary’s.

Interestingly, the installation of the cable reduced electricity prices for islanders and allowed the introduction of Economy 7 using electricity from the mainland.

Isles of Scilly 33kV Undersea Cable

Isles of Scilly 33kV Undersea Cable

Isles of Scilly 33kV Undersea Cable

Isles of Scilly 33kV Undersea Cable

Isles of Scilly 33kV Undersea Cable

New Submarine Cable for the Isles of Scilly (ex Rioja 1)

As announced earlier this year, BT is planning to reuse redundant submarine cables to improve connectivity for the Isles of Scilly.  It was said that cables running from UK to Ireland and UK to Spain would be reused.

It now emerges that this is thought the redeployment of the out of service Rioja 1 cable which linked Porthcurno to Santander, Spain which has been redundant since 2006.

The cable was cut 15km from shore, and an 85km section recovered from the seabed using cable ship CS Resolute.

The cable was landed at Portcressa beach on the Isles of Scilly on 23rd July 2014 and relaid back to the mainland for reconnection approximately 15km offshore.

Isles of Scilly Roija 1 Cable Redeployment

Isles of Scilly Roija 1 Cable Redeployment

Isles of Scilly Roija 1 Cable Redeployment

Further information in the Kingfisher Bulletin (iss 12, 2014) here.

BT Press release: here.

 

Kingfisher Bulletins

Kingfisher Bulletins have been produced every two weeks for the past 15 years and are produced to improve the safety of fishing activities in the vicinity of offshore developments, or activities.

They can be found here.

Terrestrial Segment Repeater Stations


From the TyCom cable landing stations at Pottington and Highbridge, the land segment of the cable travels through Wiltshire, Berkshire and Buckinghamshire to Stratford in London.

From here it travels through Herefordshire, Bedfordshire and Northamptonshire, and then through Leicestershire, Nottinghamshire and then in to Yorkshire, terminating at Hunnamby.

Along the way, the signal requires regeneration every 73km approximately (with a tolerance of approximately +/-3500m) and so building to house the repeater equipment is necessary.
The photos here are of one example site.

New Scottish Inter-Island Submarine Cables

BT announces 20 new fibre optic submarine cables.

Largs – Millport
Kilchattan Bay – Millport
Rothesay – Toward
Kilfinan – Lochgilphead
Campbeltown – Shiskine
Corrie – W. Kilbride
Jura – Port Askaig
Glenbarr – Port Ellen
Jura – Ormsary
Kilchoan – Tobermory
Craignure – Oban
Ardgour – Onich
Stornoway – Ullapool
Lochmaddy – Leverburgh
Carnan – Dunvegan
Ardvasar – Mallaig
Dervaig – Scarinish
Lochboisdale – Eriskay
Eriskay – North Bay
Evie – Westray

St Margaret’s Bay Cable Landing Station – Ulysses-1 Cable

The image above is thought to be the Ulysses Cable landing station close to St Margaret’s Bay.  This is quite small compared to other cable landing stations, probably due to the interconnection point of Ulysses-1 and Ulysses-2 (which lands at Lowestoft), being in London (see: http://en.wikipedia.org/wiki/ULYSSES_%28cable_system%29) where users of the cable can connect to either leg.