Sustainable Infrastructure Is a Two-Way Street: Balancing Environmental and Condition Performance Goals

Abstract

Transport agencies are under increasing pressure to mitigate the global warming impact of our pavement systems. This objective, however, must be carefully balanced with other performance metrics of interest (e.g., pavement condition) for federal and state agencies. This paper details a network-level tool aimed at supporting transport agencies in achieving two competing objectives: (1) maximizing the number of pavement segments in a good state-of-repair; and (2) minimizing the global warming impact of the network. The stochastic optimization model follows a two-stage bottom-up approach, where optimal policies are learned for individual facilities, and those decision-rules are subsequently used to guide the allocation of resources across the network. The model is applied to a realistic roadway network composed of 159 miles of pavement segments based on data made available via the Highway Performance Monitoring System. The case study results highlight that, over a 20-year analysis period, maximizing the condition of pavement assets across the network increases its expected global warming impact by 1% to 8%. The results also highlight that, invariant to the selected objective and/or available budget, increasing the allocation of funds toward rehabilitation activities rather than reconstruction treatments improves the overall condition of the network by as much as 25% and reduces its global warming impact by up to 7%. The results of the case study provide decision-makers with important insights around the impact of pavement management performance goals and budgetary policies on the global warming impact of pavement systems.