Large distribution networks often need to be modified to meet new demands. Designers use CAD and load-flow simulators to determine the characteristics of gas, liquid, and electric power distribution networks. Running the simulations required to engineer changes to a network is a lengthy process. The number of alternatives which can be explored depends upon the number of simulations which can be fit into the time allotted for design. Removing unimportant detail from a complete network representation results in a shorter per-simulation run time. Leaf pruning and node consolidation are two methods used to remove such details. These methods rely on the characteristics of the graph representation of the network, and so should apply to all steady-state load-flow simulations. Using leaf pruning and node consolidation together, per-simulation time can be cut tenfold, usually without significantly affecting total simulation accuracy. A reduction in per-simulation time translates into a less costly network analysis of the same quality as previously possible, or a more thorough analysis of network characteristics in the time period set aside for design. Steam distribution networks are used to illustrate the methods discussed.