'ChallengingS' evernTunnel electrificationcompleted
GREATWesterRn ailwayClass 80x bi-mode trains are now operatingin electricmode over the entire Paddingtonto Cardiff route after the completionof electrificationin the Severn Tunnel.
Electricoperationthrough the four-mile 628-yard-longtunnel beganofficiallyon June5, markingthe completionof the much-delayedGreatWestern RouteModernisation.However, industry sourcessuggestthe tunnel hasbeen'live'since mid-May.
Upgradingthe 134-year-old tunnel for electrictrains has provedto be even more challengingthan expected for NetworkRail,requiringthe organisationto seekexpert internationalassistance.
Ratherthan standardcatenary with contactwires,25kVpower is suppliedto trainsvia fixed aluminium barsbolted to the tunnel lining.
NR'sengineershavealsobeen facedwith seriouscorrosion issuescausedby the ingress of seawater and the very wet environmentinsidethe tunnel.
Morethan 14million gallons of water are pumped out of the tunnel everydayto stop it being inundatedbythe SevernEstuary above.Sudbrookpumping stationisalsosetto berenewed aspart of the tunnel upgrade.
GWRhasbeenoperatingan improvedtimetable on the South Walesroute sinceJanuaryw, ith moretrainsand accelerated schedulesmadepossibleby the useof electrictrains,with the exceptionof the SevernTunnel section.
Aswell asimprovinginter-city servicese, lectrificationto Cardiff supportsthe WelshGovernment's plansfor a SouthWalesMetro aroundthe capital,an integrated transportsystemacrossthe whole of Wales,and a long-term visionfor a SwanseaBayMetro.
RailMinisterChrisHeatonHarrissaid:"It'sfantasticto announcethe line betweenthe capitalsof Walesand Englandis fully electricat last,benefiting both passengersandthe environment:'
Secretaryof Statefor Wales SimonHart added:"It is crucial that Waleshascutting-edge transport linksto help people travelto work,encourageinward investmentand better connect it to the restof the UKin orderto boost prosperity:'
Electrificationof the South
WalesMain Linewas originally intendedto continueto Swansea, but the line west of Cardiffwas one of severalsectionsshelved to savemoneyin 2016/17after coststripled from £640millionto £1.74billion.
The£Sbillionmodernisation projectwasfirst announcedin July2009and finally giventhe go-aheadin stagesin 2010/11.
It alsoencompasseseveral largeresignalling,enhancement and renewalschemesa, nd wasoriginallyexpectedto be completedin 2016/17.