Countries around the world continue to privatise the construction, rehabilitation and maintenance of portions of their highway network. A new trend points towards the move from highway infrastructure concessions on a small portion of the network to privately financed network management contracts covering the majority (or the whole) of a country's road network. Governments preparing this type of long-term contracts need to study carefully the implications of privatisation and ascertain whether they yield good value for money before embarking in such contracts. Similarly, companies interested in bidding for network management contracts need to decide whether the project is affordable, bankable and offers a good return to their investment. This paper addresses these issues, discussing the way in which a highway authority or a private company would estimate the long-term pavement rehabilitation and maintenance expenditure profile for the duration of a concession contract. The discussion is based on experiences obtained during the development of the Slovenia Private Roads Maintenance Project, which encompasses the privatisation of the whole of the country's primary road network to a number of concession companies. The study included the definition of the extent and condition of the road network as a starting point, followed by an analysis of its deterioration and maintenance effects from a number of maintenance strategies, resulting in a preferred long-term rehabilitation and maintenance expenditure profile. Probabilistic deterioration prediction models were used in the study. The lack of information on pavement deterioration resulted in the calibration of such models using a panel of local pavement experts and an innovative methodology for the determination of deterioration probabilities. Such deterioration models were calibrated for a combination of traffic levels and climatic conditions. The maintenance strategies included in the study were aimed at achieving the pre-defined level of service in the whole network, while resulting in good value for money to the Directorate of the Republic of Slovenia for Roads. Competing strategies covered a range of prioritisation rules and generic maintenance treatments, all resulting in a different long-term rehabilitation and maintenance expenditure profile. The selection of the most economically viable and financially attractive profile was based on the overall discounted cost of the concession contracts, the phasing of them and the financial costs attached to the various shapes of the expenditure profile. For the covering abstract see ITRD E135448.
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