With its complex geology, Iceland presents a range of challenges to tunnellers. The desire for new passages to be blasted through mountain ridges comes from the country’s small population seeking improved and safer, transport links over the island’s rugged terrain. Long and exposed winding roads snaking up valleys or round the steep edges present difficult and timeconsuming journeys, especially during the severe winters and long hours of darkness.

Going underground, therefore, can offer benefits both locally and, on a cumulative basis, nationally – even if the traffic volumes are relatively small in general.

The tunnel solutions for the road network have come as single tubes of generally increasing length over the recent decades since the late 1940s, culminating in the longest scheme so far, Hedinsfjordur Tunnel, which has two tunnels of 11km totallength and was opened to traffic in October by the Icelandic Road Administration (ICERA), or Vegagerdin.

Iceland’s road tunnels, including the two that form the Hedinsfjordur project – Olafsfjordur and Siglufjordur – are near the coast and have been excavated by drill and blast, including the first subsea crossing, at Hvalfjordur, which is its only toll tunnel, so far. That financing model is being considered for the 11th tunnel scheme on the island, Vadlaheidi, near Akureyri, the main town in the north of the country and not so far from the latest addition, Hedinsfjordur.

Traditional Nordic excavation by drill and blast has dominated the road tunnel market in Iceland and while no role has been played as yet by TBMs – unlike the construction of hydropower tunnels in Iceland, which are also more inland and generally longer – the possibility is there. At least on one prospective large road tunnel project being studied, at Mid- Austurland, in east Iceland, which could see TBMs involved.

An immersed tube is one of the alternatives for the Sundabraut crossing within the capital, Reykjavik, though it is squaring off against a bridge option and a rock tunnel in a tough economic climate.

Road tunnels – built
The 10 tunnel schemes in Iceland range from the shortest, Arnardalshamar, opened in 1948 near Isafjordur in the northwest of the country at barely 30m long, to the longest, Hedinsfjordur. The most recent addition, though by only a week, the Hedinsfjordur scheme consists of two tubes – Olafsfjordur (7,100m long) and Siglufjordur (3,900m).

Most of the bores in the road network, except for two – Oddsskard (640m, opened in 1977) in the east and Straka (800m, 1967), near Siglufjordur, are well over 1km in length and carry two-lanes. Opened in 2005, the Almannaskard tunnel in the southeast is the shortest double lane tube at 1,300m long.

However, there are longer single lane tunnels (with regular widened sections for passing points), such as Muli (3,395m, 1991), near Olafsfjordur, and also Breididalur (4,150m, 1996) and Botnsdalur (2,900m, 1996) which form two branches out of three in the near T-junction on a major northwest scheme.

The other three double-lane road main tunnels in Iceland are Faskrudsfjordur (5,900m including 200m of concrete portals, opened in 2005), the Hvalfjordur subsea tunnel (5,770m, 1998) and the Oshlid Tunnel (5,400m), which opened in September 2010.

Oshlid Tunnel was built between Isafjordur and Bolungavik in the northwest of the country by a JV of Marti with local firm Islenskir adalverktakar. Excavation of the tunnel – 5,156m of which was in rock – was subcontracted to Slovakian firm Tubau, and 600m of concrete portal was built by a local firm, Vestfirskir verktakar.

There is also another double-lane tube, which is part of a larger scheme mentioned before and is the third tunnel of the three in the northwest T-junction scheme – Tungudalur (2,100m, 1996).

Road tunnels – Planned
Iceland has had a number of potential road tunnel projects under study for years and is gradually completing them in order, and while the weakened national economy presents a challenge for financing at present and the near future, the country has strategic plans to develop further schemes.

Despite the funding challenges to foreign travel, for the time being, this strategy needs the Icelandic tunnellers to stay active and linked with the peers internationally, to discuss the experiences and lessons of tunnelling with mainly basalts, tectonically active areas, groundwater problems and rapidly changing sequences of strata.

Hreinn Haraldsson, director general of Vegagerdin and also the current president of the Icelandic Tunnelling Society, says: ‘We not only want to, but we must continue to be involved in the international community because we will construct a lot of tunnels in future.’

Key road tunnel projects in preparation or in studies, for development in the near future, in Iceland, include: Vadlaheidi, Nordfjordur, Arnarfjordur-Dyrafjordur, Sundabraut, Mid-Austurland, and another tunnel under Hvalfjordur.

In the longer-term, Vegagerdin is examining road tunnel projects at Lonsheidi and Vopnafjordur-Herad.

Vadlaheidi Tunnel
Vadlaheidi road tunnel is planned to be built through the mountain ridge forming the east side of the fjord at Akureyri, the main town of north Iceland. The tunnel is designed as a single tube approximately 7,800m long. The tunnel is to be 9.5m wide and maximum clearance for vehicles is a standard 4.6m for Iceland.

The scheme was envisaged in 2007 on a BOT model and then the planning anticipated tendering possibly in 2008. However, the project has yet to go ahead due to the tightened financial climate, of the last couple of years.

Talks are now underway with pension funds about loans to fund the project. As the state can’t take the loan, Parliament has decided to establish a special purpose company, 51 per cent held by Vegagerdin and the balance by local interests, to undertake the project. Once the pension funds involvement is determined then it will become clear if an open call for international funding will also be made.

If funding agreement is reached with the pension funds before the end of the year then Vegagerdin would expect a prequalification call to contractors in early 2011 and tendering shortly after for award around mid-year and work starting by the third quarter. The project is expected to take three years to complete.

Vadlaheidi is projected to attract 1200 vehicles per day, and traffic is estimated to increase 8 per cent in first year of operation and 3-4 per cent annually afterwards, in the short-term.

Nordfjordur Tunnel
In the east of Iceland, a single tube road tunnel is being studied in the area between Eskifjordur and Nordfjordur. Plans in 2007 envisaged a 6,200m long tube with a T-8 profile and the project going to tender in late 2009 for award for construction to start in 2010. Geology is basalt with interbedded sedimentary layers.

Still in planning, the tunnel is now planned to be 7,800m long including the concrete portals, with a width of 8.5m and the standard 4.6m maximum height clearance. The project is almost ready to tender and bid call is expected in late 2011 for construction to start in 2012. However, due to the challenges facing the public funding route this three-year project may be postponed even further.

Arnarfjordur-Dyrafjordur Tunnel
Located in northwest Iceland, between the fjords of Arnarfjordur and Dyrafjordur, slightly south of the Oshlid Tunnel and also the T-junction of the Breididalur, Botnsdalur and Tungudalur tunnels, this project has been examining different alternatives at lower and higher altitude. The present plan is for a 5,300m long single tube with a T-8 profile. Geology is basalt with interbedded sedimentary layers.

Sundabraut Tunnel
The intended project site is the northern part of Reykjavik but the proposed 4,400m long, undersea double tube (T-9.5 profiles) scheme is competing against a bridge option and an immersed tube in the current difficult financial climate. The project is to be jointly developed by Vegagerdin and city. The geology in the area is basalt and palagonite – altered volcanic basaltic glass.

Mid-Austurland Tunnel
The project is located in east Iceland and could involve a series of road tunnels between the town of Egilsstadir and others on the coast, to the east and southeast. Studies have identified up to 14km of tunnel across the various alternative routes and tube combinations.

Depending on the elevation above sea level and number of links, there could be a single tunnel that is 11-14km long, or two tunnels with a combined length of 10- 14km, or further alternatives. The scheme envisages a single tube with possibly an additional escape tube.

Hvalfjordur – expansion
The subsea toll crossing, which is slightly north of Reykjavik and provides a fast link to Akranes, was conceived as a possible scheme in the 1960s. Development finally got underway in the 1990s under a special purpose company, Spolur, which has public and private interests and was authorised by Parliament.

Almost two-thirds – 3,750m – of the tunnel is below the sea bed and at its lowest point the tube is 165m below sea level. The contractor was a JV of Istak, Skanska and Pihl & Son. Excavation was done over 1996-7 and achieved a best monthly advance of 517m.

A second, parallel subsea tunnel is being examined to meet safety requirements in future when traffic volumes approach 10,000 vehicles per day. No decision has been made on the financing structure. The tunnel might be built within the next 10 years.

Works at Muli and Straka
The Muli and Straka tunnels are the original tunnels in north Iceland that precede Hedinsfjordur Tunnel, and in fact were the coastal, single tubes – to the south and north – that eased access to Olafsfjordur and Siglufjordur, respectively. Increased traffic volumes and public demand following the recent opening of Hedinsfjordur Tunnel will determine how much of a bottleneck the older, shorter and smaller tubes may represent and which alternatives there are to improving traffic capacity into the area.

Talking Tunnels
In holding the presidency of the Nordic Road Association (NVF) and as a member of the Executive Committee of PIARC (World Road Association), Haraldsson is intensely involved, as he has been throughout his career, in the benefits of constructing and operating roads in Iceland.

In 2012, Reykjavik will host NVF’s Nordic Road Congress for the first time.

Iceland will benefit from, and continues to seek and need, good contact with the tunnelling community abroad, he says.

Location of the key road tunnels built and in planning in Iceland Ranking of built road tunnels in Iceland, the longest being the most recently built – Hedinsfjordur Tunnel Project, which includes the Olafsfjordur and Siglufjordur tunnels The newest road tunnel in Iceland – Hedinsfjordur Tunnel – was built by Metrostav-Hafell JV and consists of two single tubes, Olafs and Siglu, together make the scheme the longest in the country Hreinn Haraldsson, director general of Icelandic Road Administration, Vegagerdin, and president of the Icelandic Tunnelling Society Hedinsfjordur Tunnel was opened on 2 October 2010, and links communities separated by long, often impassable roads in winter on the coast of north Iceland Difficult geology and groundwater ingress were significant aspects of drill and blast construction of Hedinsfjordur scheme, particularly on parts of Olafsfjordur Tunnel