Use of Treated Wastewater in the Construction of Base Course Layers for Sustainable Pavement Structures

Abstract

This study was conducted to investigate the potential of using treated wastewater in the compaction of base course layers in pavement structures. Three different types of base course material and two sources of treated wastewater in addition to tap water were considered. Chemical analysis tests were conducted on the treated wastewater (TWW) to evaluate the suitability of their use in construction. Modified Proctor compaction and California bearing ratio tests were conducted on the prepared road base samples. In addition, pavement analyses were performed using the Mechanistic-Empirical Pavement Design Guide (MEPDG) to evaluate the effects of using TWW on the pavement performance. The economic and environmental impact of using TWW in pavement construction was also evaluated. The results of this study indicated that TWW can be a suitable replacement for fresh water in base course layers in pavement construction. The cost and environmental impact analyses showed that using TWW in base layers can result in up to 68% reduction in water cost and can have a clear positive impact on the environment.