The dynamic optimization of large interconnected sets of differential equations in state space form is considered within the context of some civil engineering applications. The theorems of duality for static problems are extended to the dynamic case to provide the basis for an iterative two-level computational algorithm based on price directive dual coordination. Computational results from a number of spatially and time decomposed applications are presented, including production and inventory planning, minumum energy operation of water supply networks, urban traffic transportation systems, and environmental pollution control. These computational schemes may be of more general interest to other areas of civil engineering optimization to which they have not yet been applied.