Natural disasters and calamities are virtually unavoidable. Due to increasing occurrences and severity, organizing relief operations have become increasingly difficult to conduct. With many similarities in its components and activities, the difficulty of relief operations may be tackled through a supply chain approach birthing the application of Disaster Supply Chains. The biggest concern in disaster supply chains is the assurance that relief goods are supplied at the right location and at the right time. By using a two-stage deterministic linear programming model, the amount of inventory allocations and deliveries are optimized throughout a three-echelon system. The proposed model decides on the optimal quantity to deliver and uses a binary function to route it through the appropriate transportation modes with respect to varying lead times, capacities, and costs at key locations. This proposed model is validated through different scenarios with varying input parameters which determine sensitive points in the model.