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Universal Bridging Consortium (UBC) has published a proposal to develop a 14km bridge linking Kangaroo Island to the South Australian mainland potentially through a public-private partnership (PPP). If built, it would be one of the longest overwater vehicle bridges in Australia.

Located 110km south-west of state capital Adelaide, Kangaroo Island is home to around 4,700 people. Over a third of the island is protected in nature reserves, making it a key eco-tourism destination, attracting around 250,000 visitors a year. However, the island is only accessible by air and sea.

UBC has proposed a multi-span cable-stayed bridge, with 400m-long  spans and four lanes, estimating capital costs between AUD4 and 5 billion (US$2.96 and 3.70 billion). The bridge would follow ferry routes, linking the Fleurieu Peninsula of South Australia to Kangaroo Island south-east of Penneshaw.

The consortium projects that this would reduce travel time to and from the island from around 1.5 hours by ferry to about 15 minutes. The bridge would make the island a two-hour car drive from Adelaide’s CBD.

The project has already received significant political support. One of the members of the South Australian Legislative Council, Frank Pangallo, has added his voice to UBC's call on the state government to authorise AUD100,000 (US$74,000) public funds for a pre-feasibility study. However, it faces considerable opposition from others. 

The Mayor of Kangaroo Island has publicly voiced his hostility to the plan, citing concern for the effect on ferry businesses and opposition to the island becoming a mass tourist attraction. More tourists could potentially spoil the island's natural beauty and community focus on preservation. There are also key economic concerns, with the island's population thought to be too small to handle a large increase in visitors.

UBC argues that access to Kangaroo Island currently makes it available only to tourists with high disposable incomes, which is not fair to residents of South Australia and visitors. Thus, the bridge proposal has highlighted interesting questions regarding tourism strategies.

For now, the Minister of Infrastructure of South Australia has said that the bridge is not a priority, meaning that it is unlikely to gain government funding in the near future.

UBC is a registered subsidiary of a local consulting firm, JNC. Technical planning and design work on the proposal was carried out by Adelaide-based firm The Space Laboratory.