Asphalt pavement performance is profoundly impacted by the presence of water and moisture in the road, resulting in substantial costs to society. Research showed that significant portion of the road sections need early maintenance measures regardless of traffic volume due to moisture-related damages. Monitoring moisture conditions, preferably using a non-destructive continuous method, is thus vital to the decision-making and selecting appropriate maintenance intervention. Furthermore, understanding moisture conditions is critical for accurately interpreting automatic road condition measurements, especially during the spring (thawing) when the roads exhibit the lowest load bearing capacity due to increased levels of moisture. This study employed a multi-receiver Ground penetrating radar (GPR) and a Falling weight deflectometer (FWD) measurements to assess moisture levels and structural condition of an indoor full-scale test road. The groundwater level of the test road was varied by introducing water to the system. The results revealed a good correlation between the FWD and the average GPR velocity measurements. The GPR measurements provided a relative water content of the test roads. Further exploration of other GPR parameters, such as frequency, magnitude, and amplitude of the GPR signal is recommended, as these may offer an even better correlation to moisture content.