This paper proposes a new model for design of sustainable bi-modal transportation networks under demand uncertainty, with chance constraints on emission and equity issues. The proposed model is formulated as a bi-level programming problem. The lower level is a reliability-based traffic assignment problem for bi-modal transportation network, in which the transfer waiting time and non-linear bus fares are considered explicitly so that the passengers’ behaviors on mode choice and path choice are simultaneously taken into account under demand uncertainty. The upper-level design objective is to maximize the network reserve capacity in terms of the summation of weighted mean and standard deviation of travel demands. A heuristic solution algorithm...