The impact of fixed link projects to islands on accessibility and population development
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Norway has a long coastline, with many islands and fjords. Ferries play a vital role in enabling people to access these islands and to cross the fjords. However, in recent decades, several ferry services have been replaced by bridges or subsea tunnels with the goal of reducing both travel time and the barrier effect of scheduled ferry service. Projects that use bridges and subsea tunnels to replace a ferry service are called fixed link projects. Direct impacts Fixed link projects offer direct benefits to travellers crossing a fjord. For example, travel time is reduced, and capacity is increased; furthermore, unlike a ferry, which is only open for a few minutes around scheduled departure times, the fixed link is open all the time. The benefits for users are calculated based on the number of users and the reduction in the generalised cost of travelling. These user benefits are part of the assessment of new projects in Norway and constitute a large portion of the benefits of a fixed link. The nature of a scheduled service means that travellers dependent on ferries are subject to some inconveniences. These inconveniences may consist of both open and hidden waiting times as well as issues of reliability and punctuality. Open waiting time is the actual waiting time at the ferry quay whereas hidden waiting time relates to the inconvenience of being dependent on a scheduled service. These two factors are assumed to have the greatest impact on the inconvenience of ferries. This thesis includes an analysis of the relationship between open waiting time and frequency. Using linear regression techniques, this study suggests that open waiting time is slightly longer than that shown by today’s assumptions. Furthermore, the study shows that there is a substantial difference between national highway ferry services and local ferry services. The results from the study show that local services have a shorter open waiting time. Compared to national services, the local services included in the study have a larger share of frequent travellers; these travellers might be more experienced than infrequent travellers and thus know how to adjust to the time-tables. Increased knowledge of open waiting time is also important for future studies on hidden waiting time as hidden waiting times for ferries are not addressed in the current literature. Impacts on the housing market and population development It is argued that fixed links strengthen the connection between residential and labour market regions on each side of a fjord. Hence, a fixed link may affect both population development and the labour market in the area where it is located. In this thesis, the impacts on population development and the labour market are investigated through ex-post case studies of the islands connected by a fixed link. The variables included in the case studies are travel demand, housing prices, population numbers, population movement patterns, employees and commuting patterns. The variables are analysed using a difference-in-difference approach to correct for counterfactual development in the variables. The results from the case studies show that fixed links induce growth in traffic volume, population and housing prices on the connected islands. In particular, fixed links close to cities lead to large growth in these variables. The increase in population on the islands to a large extent originates from the mainland. The results indicate that a fixed link makes the connected islands more attractive in terms of residential settlement through both increased prices for residential housing and population growth. Furthermore, population development promotes increased interaction between island and mainland as traffic continues to grow. Rural cases experience less growth than those close to cities, and some cases do not experience any growth related to the fixed link during the tolling period. However, signs of development are also observed for these cases after the tolling period ends. Hence, tolling might restrain development in rural cases, delaying their potential development. The case studies show that a substantial part of the population growth in the islands originates from the mainland which the island is connected to or other parts of the county. This finding suggests that the population effects on the islands are caused by a re-distributional effect rather than net population growth in the influential area. One reason for people moving to the islands might be cheaper housing prices, as they are able to purchase a large detached house for the same amount of money as a smaller apartment in the city. In addition to the case studies, a quantitative analysis of housing prices has been conducted. Through hedonic regression modelling, the internal and external characteristics of residential housing are investigated to determine how they affect housing prices. According to the analysis, distance to the regional centre is an important external characteristic. This finding is consistent with the case studies that are conducted close to cities/regional centres experiencing larger growth than the more rural cases. Implications for Norwegian assessment methods The Norwegian assessment methods used to analyse transport investment projects include the direct impacts of the projects. Nevertheless, these methods have some potential shortcomings. The direct impacts related to ferry services have some potential weaknesses. The travel time estimations, especially the size and value of the inconvenience cost of travelling by ferry, are still under debate in Norway. Some improvements have been made to the transport model used to analyse these factors. However, the analysis of open waiting time in this thesis, along with other new literature on this topic, may suggest that further improvements could be made to the transport model. A distinction between national highway services and local services might also contribute to better estimations of open waiting time. Additionally, more research on other elements of the inconvenience cost should be explored further such as hidden waiting time, reliability and punctuality. Another important element to address in today’s assessment methods is the secondary impacts from projects such as fixed links. The impacts on housing prices/land value and population development are not accounted for in the assessment methods used today. Population prognosis is held fixed among the alternatives. The findings from this thesis show that fixed links have an impact on population development, and that impact is not currently accounted for. Future improvements to the assessment methods should focus on ways in which to include these secondary effects in the present assessment methods. Incorporating these effects might improve accuracy when relating traffic demand to tolling analysis, conducting project and environmental assessments and providing information on regional population development.