All electric utilities serve power to their customers through a variety of functional levels, notably substations. The majority of these components consist of distribution substations operating at lower voltages while a small fraction are transmission substations. There is an associated geographical area that encompasses customers who are served, defined as the service area. Analysis of substation service areas is greatly complicated by several factors: distribution networks are often highly interconnected which allows a multitude of possible switching operations; also, utilities dynamically alter the network topology in order to respond to emergency events. As a result, the service area for a substation can change radically. A utility will generally attempt to minimize the number of customers outaged by switching effected loads to alternate substations. In this manner, all or a portion of a disabled substation's load may be served by one or more adjacent substations. This paper describes a suite of analytical tools developed at Los Alamos National Laboratory (LANL), which address the problem of determining how a utility might respond to such emergency events. The estimated outage areas derived using the tools are overlaid onto other geographical and electrical layers in a geographic information system (GIS) software application. The effects of a power outage on a population, other infrastructures, or other physical features, can be inferred by the proximity of these features to the estimated outage area.