The aim of this study is to examine further the new capacity-reliability index recently proposed for the design of a new reserve capacity model for a signal-controlled road network. This new reliability index explicitly accounts for the probability that all network links would be operated below their capacities when serving different traffic patterns deviating from the average condition. Specifically, the reserve capacity model is reformulated by using the new reliability index in a bilevel optimization framework. In addition, the reliability-based design is compared with that of the reserve capacity model to gain insights between the deterministic and stochastic network design problems.