thumb|[[Stord Bridge with Stord in the background]]

The Triangle Link () is a fixed link with three branches connecting the islands of Stord and Bømlo to each other and the mainland at Sveio, Norway. It consists of the underwater Bømlafjord Tunnel from Sveio to the island of Føyno, the Stord Bridge from there to Stord, and a road including the Bømla Bridge and the Spissøy Bridge to Bømlo. The section from Sveio to Stord is part of European Route E39, while the branch to Bømlo is part of County Road 542.

The Bømlo Tunnel is long and reaches below mean sea level. It is the longest subsea tunnel in Norway and was the deepest in the world when it opened. The Stord Bridge and Bømla Bridge are both suspension bridges, with lengths of and main spans of . The Spissøy Bridge is a beam bridge. The link is long toll road with a toll plaza on Føyno. The section from Stord to Bømlo has a pedestrian and bicycle path.

Plans for a link between Bømlo and Stord were first launched as a pontoon bridge in the 1960s. In the late 1980s, the plans evolved into a triangular project. There was controversy surrounding the project, in particular from environmentalists. The Parliament of Norway passed the plans in 1996, and construction started the following year. The bridges and link between Stord and Bømlo opened on 28 December 2000, while the tunnel opened on 30 April 2001. The link cost 1.8 billion Norwegian krone (NOK) after substantial cost overruns and remained a toll road until 30 April 2013.

Route description

thumb|Overview of the Triangle Link, with the Stord Bridge to the left, the Bølmo Bridge in the middle, Spissøy Bridge to the right and the Bølmafjord Tunnel below the fjord up to the right

The Triangle Link is part of two routes, European route E39 and County Road 542. The section from Stord to Sveio, including the Stord Bridge and the Bømlafjord Tunnel, is part of the E39 highway (the Coastal Highway) which runs along the west coast of Norway. The section from the interchange on the island of Føyno, including the Bøla Bridge and the Spissøy Bridge, is on County Road 542. The link acts both as a mainland connection for Stord and Bømlo to the mainland at Sveio, as well as a link between the two island communities, which have a combined population of 30,000.

The Bømlafjord Tunnel is a long subsea tunnel which crosses Bømlafjorden. It is wide, tall and reaches below mean sea level. The tunnel has three lanes, one downhill and two uphill, with the direction of the extra lane switching at the bottom. When it opened, it was the longest and second-deepest subsea tunnel in Europe. The pylons were built in concrete, while the deck is built as 19 in steel sections, each long and weighing . It has the fifth-longest span in Norway.

The tolls are collected at a toll plaza located on Føyno. The plaza is constructed as a grade-separated intersection, so that any car passes through the plaza once. However, traffic only traveling between Føyno to Bømlo does not have to pay. Cars driving along E39 drive straight ahead through the plaza, while cars to or from Bømlo need to use the interchange. There is also an intersection allowing access to the island. The plaza has six lanes, of which two in each direction have a toll booth and one in each direction has an automatic collection. The toll station uses the Autopass toll collection, which allows passage without stopping, in addition to manual collection. Passengers, pedestrians, bicycles, motorcyclists and mopeds are free. After a restructuring of the toll costs in 2006, the fees were NOK 85 for cars and NOK 270 for trucks, having previously had two separate fees for small and large trucks. Frequent travelers can prepay for at least 40 passings to the toll company, and receive a 40 percent discount.

A new route was launched by Bømlo Mayor Malvin Meling, who proposed a pontoon bridge which would cross Stokksundet. He was inspired by the plans to build what would become the Nordhordland Bridge north of Bergen. In 1973, the municipal councils of Bømlo, Stord and Fitjar decided to launch a planning process, which concluded that a pontoon bridge between Sørstokken and Foldrøyholmen would be optimal. The report also considered bridges across the Fitjar Archipelago and a crossing via Spissøy and Føyno. There were protests from Wichmann Motorfabrikk who were concerned about their operations if the sound was closed for shipping traffic. The shipping industry received support from Norwegian Coastal Administration and the plans were abandoned in 1974.

Mapping of traffic patterns on Bømlo was undertaken by Hordaland Public Roads Administration in 1984, and based on this and other feedback, a pontoon bridge between Foldrøyholmen and Sørstokken was recommended. It was estimated to cost NOK 190 million, in addition to auxiliary roads for NOK 40 million. Following the opening of the Vardø Tunnel in 1982, the first subsea tunnel in Norway, Engineer Finn Nitter d.e. proposed a fixed link which involved a combined bridge, road and tunnels between the islands, including a suspension bridge over Digernessundet, a causeway and low bridge onwards to a subsea tunnel under Spissøysundet and a low bridge over Gassasundet. In addition, a long tunnel would have had to be constructed from Føyno to Ulveråker in Sveio.

A new master plan for the project was completed by the Public Roads Administration in December 1986. It proposed four main routes: via the Fitjar Archipelago; via Foldrøyhamn with a pontoon bridge to Sørstokken; a suspension bridge from Søtreneset to Stokkbleikjo; or via Spissøy, Naustøy and Føyno to Digernes. They recommended choosing the pontoon bridge. SBT stated that this was only to be a first stage, and that a second stage should involve a tunnel to the mainland. In a meetingbetween SBT and representatives for the shipping industry at the end of 1986, it was decided that SBT would start working for a mainland connection that would not hinder sailing.

A report published by SBT in 1987 looked at details for a subsea tunnel to the mainland. It was the first official document to use the "Triangle Link" term, although this had previously been used by the press. A delegation traveled to Washington state in the United States and British Columbia in Canada to look at their seven pontoon bridges, while seismic surveys were undertaken in Bømlafjorden. SBT changed its name to Sunnhordland Bru- og Tunnelselskap and a majority of the board shifted towards being in favor of a fixed link. The issue became the subject of major local debate and was supplemented by a demand from residents in southern Bømlo that they did not want to lose their ferry service, which would be faster than driving via the fixed link.

Opposition

The Coastal Administration stated that they would not allow a pontoon bridge. SBT decided on 26 June 1987 to work towards receiving permission to collect advanced tolls on the ferry services. On 16 September, they unanimously supported the triangular proposal, which was estimated to cost NOK 660 million. This was criticized by Hordaland Public Roads Administration, who stated that it would take longer time to plan—and thus complete—the Triangle Link. A poll from January 1988 showed that 78.6 percent of the population of Bømlo wanted the Triangle Link, while 8.6 percent wanted the pontoon bridge. On 6 January, SBT started negotiating loans with various banks to receive financial guarantees for the Triangle Link, and by February sufficient funding had been secured.

From 1988, environmentalists started actively opposing the Triangle Link. The most active was the local chapter of the Norwegian Society for the Conservation of Nature, which stated that the road would have serious consequences for the local boat traffic to the recreational islands of Føyno and Nautøy. Instead, they recommended that the municipalities chose a pontoon bridge. An action group was established. Hallgeir Matre stated that Stord had a lack of beaches and that the two islands "were the last low, forested islands in the area after the paradise<!--naturperle--> Eldøyane had been converted to an industrial area for Aker Stord during the 1970s". He further stated that environmentalists were skeptical to floating bridges, but that in this case it would be the lesser of two evils. The Stord Society for the Conservation of Nature applied for municipal grants to make a critical report, but this was rejected by the majority of the municipal council. By June, a new chapter had been established on Bømlo, and the group stated that it was irresponsible to build a link which would result in a massive increase in car use. Future In Our Hands started a petition Gisle Tjong was another opponent, who stated that the risk in the project was large and that it was uncertain how long the tolls would last: they could just as well last 60 as 15 years. Instead, he wanted to use advanced tolls and fuel fees, place the income in the bank and then pay the whole fixed link with the accumulated funds. Most of the opposition against the project was from Stord, while in Bømlo there was overwhelming support. However, in southern Bømlo there were concerns that they would lose their ferry, as they would have a much longer rout to Haugesund via the Triangle Link. Some also stated that it was necessary to keep a ferry for people with fear of tunnels.

Political processes

thumb|Entrance to the [[Bømlafjord Tunnel from the mainland]]

Bømlo Municipal Council voted unanimously in favor of the Triangle Link on 22 February 1988. Hordaland Public Roads Administration still supported a pontoon bridge, and stated that two and a half years of work on a master plan had been wasted. A new master plan for the Triangle Link was published in early 1989, estimating the costs at NOK&nbsp;890 million. It recommended that the Langevåg–Buavåg Ferry remain, but the other four ferry services be terminated. The report concluded that the maintenance costs of the fixed link would be lower than the subsidies of the ferry, that the project would be economical of society and would reduce emissions.

During late 1989, advance tolls on the ferries were approved by the municipal councils and the county council, who recommended that collection start from 1 July 1990, but this was not immediately supported by the government.

In 1991, the master plan was appealed by the Norwegian Society for the Conservation of Nature to the Ministry of Transport and Communications. The appeal was seconded by the Norwegian Directorate for Nature Management. In the 1991 municipal election, the Socialist Left Party was the only party which was opposed to the fixed link, and they received a large increase in votes, increasing for 7 to 21 percent in Stord. The same year, Dag Hareide in the Norwegian Society for the Conservation of Nature started lobbying up towards national politicians in an attempt to stop the issue in Parliament. High-profile people who were opposed to the project included Per Ståle Lønning, Herborg Kråkevik and Kenneth Sivertsen. In the council meeting on 18 June 1992, a proposal to waiver prioritization was rejected. The council then, with 44 against 30 votes, chose to prioritize the Hardanger Bridge, which received most votes from the Labour and Centre Party. The Conservative Party was the only party for which all the votes were cast in favor of the Triangle Link. The Socialist Left Party's proposal to build neither received 11 votes.

In July, the master plan was passed by the Council of State. On 10 December 1992, Parliament approved advanced payment of tolls on the ferry, which were made effective from 1 January 1993. Ticket prices increased with between NOK&nbsp;10 and 12. This resulted in protests from the ferry employees who stated that they would have to collect the tolls which would remove their jobs; Norwegian Seafarers' Union representatives stated that they considered suing the state. Work on the development plan started in 1992. It included safety and environmental improvements which increased the project's cost by NOK&nbsp;200 million. Opseth subsequently stated that in his opinion, the Triangle Link should be prioritized. In 1995, a report on the Coastal Highway (E39) was presented, which recommended that the Skjersholmane–Valevåg Ferry be removed.

Particularly within the Labour Party there was disagreement about whether or not to build the Hardanger Bridge. In addition to crossing the Hardangerfjord, there were concerns that the bridge would increase the traffic through Hardangervidda National Park, and that it subsequently would result in an all-year road being built with subsequent negative impact on nature and wildlife. Prime Minister Gro Harlem Brundtland of the Labour Party stated on 10 October 1995 that the government was in favor of the Triangle Link and opposed to the Hardanger Bridge.

Construction

Construction started on 15 February 1997. Before the first blast could be taken by County Mayor Magnar Lussand, representatives for Vestlandet Nature and Youth, and The People's Movement Against the Triangle Link had to be moved. The only police officer at the festivities was Sheriff Reidar Færestrand, who was not dressed in his police uniform and had not brought with him his badge. The demonstrators did not move until a police boat had been sent with the necessary documentation and Færestrand could prove his identity as a law enforcer. Elin Lerum Boasson of Nature and Youth stated that it was "a day of sorrow".

thumb|left|[[Stord Bridge with Stord to the left]]

Core samples showed that the tunnel would have to be built deeper than originally planned to avoid deposits. The tunneling was undertaken by NCC Eeg-Henriksen from the Føyno side and by the Norwegian Public Roads Administration from the Sveio side. Construction from Sveio started on 16 September 1997 and from Føyno on 6 March 1998. The tunnel was built at an average speed of per week, with the record being . The lowest point was reached on 5 May 1999 and the breakthrough took place on 2 September, five months before schedule. When it opened, the tunnel was the longest and second-deepest subsea tunnel in Europe and Norway, after the Hitra Tunnel. Construction started on the Stord Bridge on 20 February 1999. After the pylons were completed, two catwalks were erected between them, with the constructors choosing a continual catwalk instead of three separate ones. The two bridges were the first time that on-site spinning was used in Norway. The decks were produced in Schiedam, Netherlands, for the Stord Bridge and in Italy for the Bømlo Bridge. These were sent by barge to Sunnhordland. The section length was different between the two bridges, the Stord Bridge having them in lengths of and the Bømla Bridge in sections of . This was to accommodate the latter's smaller vertical curvature.

The entire project cost NOK&nbsp;1,814 million. The costs were distributed to NOK&nbsp;476 million for the Bømlafjord Tunnel, NOK&nbsp;433 million for the Stord Bridge, NOK&nbsp;336 million for the Bømla Bridge, NOK&nbsp;46 million for the Spissøy Bridge, NOK&nbsp;36 million for the Digernes Tunnel, NOK&nbsp;325 million for roadways and NOK&nbsp;172 for administration and common costs. The investment cost was split between state grants and NOK&nbsp;1,036 million in debt taken up by the toll company. When the project was passed by Parliament it had a budget of NOK&nbsp;1,260 million. The Office of the Auditor General of Norway criticized the Western Norway Public Roads Administration in 2001 for a total cost overrun of NOK&nbsp;900 million in three projects, the Triangle Link, the Lærdal Tunnel and parts of National Road 555. The majority of the cost overruns were tied to the Triangle Link. As a consequence, Minister of Transport Torild Skogsholm stated that future large road investments would have an external quality assurance before being presented to Parliament.

Opening and operation

thumb|[[Bømla Bridge]]

The first part of the link, between Stord and Sveio, including the Stord Bridge and Bømlafjord Tunnel, was taken into use on 27 December 2000. The official opening and the National Road 542 opening took place on 30 April 2001. The opening of the first stage allowed two ferry services to be replaced, the Skjersholmane–Valevåg Ferry, which connected Stord to Sveio, and the Skjersholmane–Utbjoa Ferry, which connected Stord to Vindafjord Municipality. With the opening of the Bømlo connection, the two remaining ferries could be closed: the Sagvåg–Siggjarvåg Ferry, which connected Stord with Bømlo, and the Mosterhamn–Valevåg Ferry, which connected Bømlo to Sveio. The Langevåg–Buavåg Ferry, which connects the southern part of Bømlo to Sveio, was not closed. In 2000, the four closed ferry services transported 884,216 vehicles and 1,935,875 people.

From the start the toll plaza used Autopass, a standard which allows automatic passage through the toll plaza without stopping. The system was launched by the Norwegian Public Roads Administration in 2001 and the Triangle Link was the first to take the system into use. The tollway was also the first in the country to allow subscriptions to be made via the Internet. Along with the company for the Osterøy Bridge, SBT received the harshest criticism in the report. Especially a trip made by Chairman Harry Herstad and his wife to San Francisco to participate at a conference was criticized, as it cost the toll company NOK&nbsp;118,000. Also annual board member fees of NOK&nbsp;200,000 and excessive trips for the board were commented as wasted money. The internal audit concluded with that there were costs of NOK&nbsp;300,000 in 2002 and 2003 which were not properly documented or were not used in line with regulations. Pål Kårbø was elected new chairman. At the same time the annual meeting demanded that the company withdraw from its various tasks related to establishing toll projects on Bølmo and Halsnøya as well as administrative work of the Norwegian Road Financing Companies Association. In a 2007 report from the Public Roads Administration, SBT was one of seven toll companies which was criticized for too high administration costs. The toll changed the operator of the toll plaza from Bru- og Tunnelselskapet to Vegamot in 2010. The same year the toll plaza had 1,910,280 passing vehicles and a revenue of NOK&nbsp;142 million. The toll collection was scheduled to be completed on 30 April 2013.

References

;Bibliography

;Notes

  • Official site