The Stord Bridge () is a suspension bridge which crosses Digernessundet between the islands of Stord and Føyno in Stord Municipality in Vestland county, Norway. The bridge is long, has a main span of and a clearance below of . It carries two lanes of European Route E39 and a combined pedestrian and bicycle pathway. It is part of the Triangle Link, a fixed link which connects Stord to Bømlo, and both to the mainland. In 2010, the bridge had an average 5,021 vehicles per day. The bridge and the link was a toll road from the opening until 30 May 2013.
Plans for a crossing arose in the 1960s; and until the 1990s proposals were for a pontoon bridge further north. The Stord Bridge was conceived after the decision to combine the crossing with the Bømlafjord Tunnel. The project was resisted both by local environmental groups and the Norwegian Public Roads Administration, the latter because the new plans would delay completion. Construction was undertaken by a joint venue between NCC and HBG Steel Structures. Construction started in 1999 and was the first bridge in Norway to have the cables spun on-site. The bridge cost 442 million Norwegian krone (NOK) and was taken into use on 27 December 2000.
Background
The motivation for the Triangle Link was the desire to have a fixed link between the islands of Stord and Bømlo. The first documented proposals were made in the 1960s and involved building a pontoon bridge across Stokksundet, 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 the shipping industry, who wished to continue to use the strait for ship traffic. The islands were connected with a network of five ferry services: Skjersholmane–Valevåg connected Stord and Sveio, Skjersholmane–Utbjoa connected Stord and Vindafjord, Sagvåg–Siggjarvåg connected Stord and Bølmo, and Bømlo was connected to the mainland both by the Mosterhamn–Valevåg Ferry and the Langevåg–Buavåg Ferry.
In the early 1980s, plans for Stord Airport, Sørstokken were launched. Thus, the plans for a bridge crossing Stokksundet were again raised in 1982, this time by the industry on Bømlo, who would have to travel by ferry to reach the new airport. A committee was established in May 1983, which gave Engineer Harald Møyner the assignment of producing a new report. He launched three proposals: a pontoon or suspension bridge between Foldrøyholmen and Litlaneset; a suspension bridge between Setraneset and Sokkbleikjo, which would terminate just south of the new airport; and a combined fixed link between Spissøy and Digernes, without passing via the Fitjar Archipelago. The latter proposal was the first time a fixed link to the mainland was proposed. The Norwegian Civil Aviation Administration protested against a possible suspension bridge near the airport, but stated that one further away would be fine.
Surveys of traffic patterns on Bømlo were undertaken by Vestland Public Roads Administration in 1984. Based on it and other feedback, the agency stated that it preferred a pontoon bridge between Foldrøyholmen and Sørstokken, north of the ferry between Bømlo and Stord. It was estimated to cost NOK 190 million, in addition to auxiliary roads for NOK 40 million. In 1982, plans were launched for a fixed link to the mainland further south, which would include a bridge over Digernessundet, a causeway and low bridge across Spissøysundet and a low bridge over Gassasundet. In addition, a tunnel would have to be built from Føyno to Sveio. This proposal was similar to the finalized Triangle Link. In 1985, an all-tunnel proposal, following the same route, was proposed. Hordaland Public Roads Administration stated that the proposals were unrealistic. The limited company Ytre Sunnhordland Bru- og Tunnelselskap AS (SBT) was founded in October 1986 by the municipalities of Bømlo, Stord, Fitjar and Sveio, Hordaland County Municipality and five banks.