Abstract Manager

The Billy-Diamond Highway (BDH) is a 620 km asphalt road built in the 1970s that crosses the Jamésie region located in northwestern Quebec and is managed by the Ministère des Ressources naturelles et des forêts (MRNF) and the Société de Développement de la Baie-James (SDBJ). In addition to linking the towns of Matagami and Radisson and providing overland access for machinery and workers to forestry, mining and hydroelectric work sites, it is the unique road link providing access to this part of Quebec's territory, which includes many First Nations communities.

Faced with the deterioration of the RBD, which is mainly attributable to the heavy vehicles using this road, SDBJ is carrying out a series of major repairs to restore the pavement's level of service. In order to protect these investments, SDBJ analyzed the impact of establishing various load regulations on the RBD. The study consisted in assessing the impact of the four load regulation scenarios, pre-established by SDBJ, listed below.

▪ Scenario A - Status quo: maintenance of the current situation, i.e. no load restriction at any time during the year.

▪ Scenario B – Loads restriction are imposed during the thaw period only, with start and end dates determined by decree in the same way as on the Ministère des Transports et Mobilité durable Québec (MTMD) network.

▪ Scenario C - Year-round load regulation identical to that in force on the MTMD network

▪ Scenario D - Year-round load regulation as described in Scenario C, as well as the authorization of a winter period surcharge.

The analysis was carried out on the economic side of road transport and on the pavement damage aspect.

The study was based on all the data provided by SDBJ and public historical data. The methodology was based on theoretical models, assumptions and values recognized in practice.

Economic analysis has shown that all load restriction scenarios have a certain impact on transport costs and on changing carrier’s behavior.

The pavement damage analysis demonstrated the weakening of the pavement during the thaw period, which justifies the impact of load restrictions during this period on pavement conservation costs and thus on pavement life extension. The results of this analysis showed that the scenario, with year-round load restrictions, is the most favorable in terms of pavement preservation costs.