Purpose
Traffic congestion in central Dublin became severe at the end of the 20th century, with thousands of heavy goods vehicles (HGVs) travelling to and from Dublin port via the city centre. The tunnel relieves surface road congestion in Dublin city centre by diverting HGVs from Dublin Port directly onto the motorway network. This has positive knock-on effects for bus users, pedestrians and cyclists travelling along the city quays, including better air quality and safer travel. To discourage commuters from using the tunnel, vehicles other than HGVs are heavily tolled at peak times. HGVs travelling north and west benefit from the expected six-minute journey time through the tunnel. A tunnel was chosen as it was decided that a surface relief road was not feasible. Dublin Bus routes 142, 33x and 41x use the tunnel to get to the port area of the city from the northern suburbs. Longer distance buses from Belfast, Derry and Letterkenny also use the route.Port tunnel project
The tunnel was first suggested in the 1990s after a number of transportation and engineering studies and was included in the Dublin City Development Plan 1999 – 2005. The project was approved following a public inquiry in 1999. The tunnel formed part of theTunnel specifications
*Length: – total project *Bores: 2 *Bore width: 11.77 m (38 ft 7.82 inches) *Lane width (two per bore): 3.65 m (11 ft 11.70 inches) *Shoulder width (two per bore): 1 m (3 ft 3.37 inches) *Bore height: 4.9 m (16 ft 0.91 inches) *Operating height: 4.65 m (15 ft 3.07 inches) *Lowest point: -30 m (−98 ft 5.10 inches) at Marino It is the fourth longest urban motorway tunnel in Europe after Madrid M-30, Blanka tunnel complex inTunnel design
The tunnel was built in five sections including a pipe-jacked section under the Dublin-Belfast railway line.Cut and cover
The "cut and cover" sections at both ends featured excavations as deep as 12 m into which horseshoe-shaped sections of reinforced concrete were cast in-situ and backfilled. The southern section, at Fairview, is 500 m long while the northern cut and cover channel from Whitehall Church to Shantalla extends over 1500 m. This work was undertaken by theTunnel boring
Both bored sections were initiated from a shaft 33 m deep and 57 m in diameter created at Collins Avenue by Mowlem in a joint venture with Intrafor of France. From here, thePipe jacking
A particular challenge was faced near the southern portals where the tunnel passes under the Dublin to Belfast railway, a line that also carries suburban and commuter services. The railway was constructed on an elevated embankment made up of soft materials resting on alluvial deposits of sand and silt. Because the railway had to remain operational at all times, the cut and cover approach could not be used. Nishimatsu constructed a pipe-jacked supporting structure for the railway 3.5 m below the surface. The tunnel was then constructed in the supported space using horse-shoe sections and backfilled. This 60 m section took 24 months to complete and resulted in the adjoining Alfie Byrne road being raised by 1.5 m. It also resulted in one incident of subsidence that closed the railway for three hours. This closure cost the contractor €300,000 in penalties – €28 per second.Other works
A new entrance and exit for the Dublin port was constructed including a new bridge over the Tolka river that connects to the toll plaza and southern portals. A new junction and underpass facilitates traffic from the East Wall Road towards the tunnel. Citybound traffic approaching the tunnel on the M50 (formerly the M1 at this point) can utilise two tunnel-bound lanes or two surface lanes that continue as the N1 toward Whitehall. Traffic emerging at the southern portal approaches the toll plaza outside the port.Tunnel operation
Following a tender process in 2005, the NRA selected Transroute International, part of France's Groupe Egis, to operate the tunnel for a period of five years with an optional renewal of two years. The service contract provided for operation, maintenance, safety, traffic management and toll collection. A new subsidiary, Transroute Tunnel Operations Ireland Ltd, was set up for the purpose. Tunnel operations, including tolling, employ between 50 and 60 people. The service contract was worth €15 million to Transroute over the five-year period. The tunnel is currently operated by Transport Infrastructure Ireland. Elsewhere, Egis was also selected to provide a central system to enable interoperability between different electronic toll collection systems in Ireland.Tolling
The tunnel is tolled, with funds collected remitted to the Department of Transport. To facilitate the ban on 5-axled HGVs in Greater Dublin, there are no tolls for vehicles in excess of 3,500 kg MLW, or for vehicles capable of carrying 25 passengers or more. The original tolling scheme saw three stages of tolling: *06:00–10:00 (Southbound) and 16:00–19:00 (Northbound) – €12 *10:00–22:00 (Southbound) and 06:00–16:00 - 19:00-22:00(Northbound) – €6 *22:00–06:00, and all day Saturday and Sunday, in both directions – €3 To alleviate congestion and due to extra capacity, these tolls have now been revised. As of 1 January 2010 the tolls are: *06:00–10:00 Monday-Friday (Southbound) – €10 *16:00–19:00 Monday-Friday (Northbound) – €10 *All other times – €3 The toll plaza is located beside the tunnel control building at the southern portal, near Dublin Port. To date, tolls have been payable either on an ad-hoc basis by cash, credit or debit card or electronically by using a tolling tag from a provider such as eFlow. Cash payments are made either to a cashier, or by dropping coins only (5c denomination and above only) into an automatic counter in certain lanes.BGA Fleming award
The project was joint winner in December 2003 of theSafety features
There are 15 pedestrian crossing points (PCPs) situated 250 m apart with emergency telephone and fire fighting niches. Additional fire hose reels are located 125 m from each niche. There are four vehicle crossover points at 1 km intervals comprising a lay-by plus emergency and recovery area. These are located under Shantalla, Collins Avenue (site of the original launch shaft), Marino and Cloisters.Controversies
Safety lapses
RTÉ's Prime Time ran two reportsHouse damage
During the hard-rock boring works vibration caused some damage. Houses in the Marino area were surveyed before and after tunnelling and necessary repairs reimbursed. There were 241 claims and these were adjudicated by a loss adjuster. A fund of €1.5 million was set aside.City centre ban
Dublin City Council's policy was to introduce a ban on trucks in the city centre between 7am and 7pm, but it agreed to delay this ban for a period of two months until 19 February 2007. This was because of opposition from the Irish Business and Employers Confederation (IBEC), the Irish Road Haulage Association and the Dublin Port Company. The hauliers cited unreasonable traffic congestion on the M50, especially during the imminent widening of the northern section while IBEC and the Port Company were concerned about restrictions on free movement of goods. The ''Sunday Independent'' ran a story on 12 November 2006 revealing the ban came into force soon after as the Tunnel opened. The then Taoiseach Bertie Ahern reportedly put pressure on the council to abandon their phased approach and initiate the ban in one go. The plan was criticised by opposition parties who said such a move would simply dump the problem onto an already "dangerously crowded M50". The M50 ring road around Dublin has since been widened to 4 lanes (3 running lanes and 1 interconnecting lane between exits) in each direction and all of the interchanges are free-flow or partially free-flow since the end of 2010. This in effect negates the concerns regarding capacity.East Link tolls
One company located south of the Liffey, Marine Terminals Ltd, considered taking legal action against the Council if it went ahead with banning trucks from the city. This was because a ban would force the company to use the tunnel, which would mean crossing the privately owned and operated East-link toll bridge, incurring a €4.80 charge each way. In response, the council agreed withHeight controversy
Even before the commencement of construction, the tunnel was criticised for not being high enough. Critics argued that it would not be able to accommodate heavy goods vehicles higher than 4.65 m (15 ft) and that it should be built with an operating height of 5.5 m to accommodate virtually all sizes of trucks. Proponents of the chosen design argued that it made best economic sense and that it would be able to accommodate most heavy vehicles with only a minor percentage having to use the surface road network. Construction went ahead as planned, but speaking at the breakthrough ceremony, Jimmy Quinn of the Irish Road Haulage Association stated that a future generation may look back and say (about the tunnel not being high enough for very high trucks): "Maybe they should have done it when they were building it." In its submission to the public inquiry, the Irish Road Haulage Association did not raise the issue of the operating height of the Port Tunnel. Among the 44 countries of the International Transport Forum (covering Europe from the Atlantic to the Urals), the 4.65m operating height of the Dublin Port Tunnel is the highest specified height. Thirty six countries have an operating height of 4m. Three countries (Finland, Iceland, North Macedonia) have an operating height not greater than 4.4m. Four countries (France, Norway, Sweden, UK) have not defined a height. Source: International Transport Forum dated 20 August 2012 https://web.archive.org/web/20150528182525/http://www.internationaltransportforum.org/IntOrg/road/pdf/dimensions.pdfWater leaks
In early 2006, media reports revealed that the tunnel was leaking substantial amounts of water. This was as a result of sub-standard concrete being poured. When the concrete was removed during remedial works, protective membranes were punctured, resulting in leaks. Once the membranes and concrete were re-instated, the leaks ceased.Cost overruns
While it is often claimed that the project went over-budget, this is not actually the case. The tender price at €457 million was for construction only while the total project cost was approximately €752 million. In September 2005, it was reported that NMI was launching a claim for an additional €300 million. The council has stated that this claim will not be met and that the total project cost remains at €752 million.Relocation of Dublin Port
In October 2006, as the tunnel neared completion, theFM radio coverage in Dublin Port Tunnel
The FM radio services rebroadcast in the Port Tunnel are RTÉ Radio 1, Newstalk, 98FM, FM104, Q102, Spin 1038 and Sunshine 106.8. Radio Nova, announced in 2015 that they were initiating legal action to have their service added.Tunnel runs
The Dublin Port Tunnel has been closed to traffic and used for 10k races on three occasions since it opened. The most recent event was held on 26 March 2017, when over 2,400 runners participated in the "Underground Run", with proceeds going to the homeless charityFootnote
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