Rail transport in Swedish wood supply – seasonal variation, system risks and mitigation costs

ABSTRACT This study examines the potential for reduced risks in roundwood transport by rail. The study quantifies seasonal variation and system risks under boreal conditions, as well as practical routines for managerial response to these. The study case is based on an integrated forest company with 11 supply terminals supplying coastal mills in mid-Sweden. The terminals were distributed from south to north Sweden, with six core terminals located in the interior- and mid-supply zones for coastal mills. The monthly flows ranged from 75 to 118% of the annual average and the monthly variability of terminal inflows was 67% higher for the interior than the mid-zone terminals. Comparing inflows between assortments, the lowest variability was for coniferous pulpwood (8%) and pine sawlogs (18%), increasing thereafter to deciduous pulpwood (28%) and spruce sawlogs (53%). Regarding rail system disturbances, the frequency of deviations from scheduled routes for the core terminals was 16–17%, resulting in canceled routes for 53–65% of deviations. Two mitigation scenarios were tested to reduce supply risks (scenario 1) and a combination of supply and system risks (scenario 2). These risk mitigation scenarios had only marginal effects on system costs (< 1%). The optimal solutions, however, involved a 4–5% reduction of truck transport output (m3km per period) and 7–8% increase in rail output. From the perspective of rail operations, interviews with service buyers and providers showed that the mitigation scenarios were fully feasible on an annual planning horizon. Further options are provided for quarterly, monthly, and weekly horizons.