GIS in Utilities

Utility Networks Modeled in GIS

One of the primary reasons why GIS has been thoroughly integrated into utility operations is the development of vector and network data models within GIS. Topological data models were a revolutionary component of GIS, and many of the most common utilities are structured as networks, comprising of topologically connected sets of edges and junctions. As an example, natural gas transmission systems largely consist of sets of connected pipes, where the connections occur at points where the gas is either split from one pipe to many or collected from many pipes into one. At any point along the network, there may be junctions that contain valves, pressure gauges, compressors, or storage facilities. Of course, there must be a production facility (or facilities) and distribution points (homes or businesses) that act as sources and sinks in the gas distribution network. Each of these network elements may have many different attribute values. In the case of the pipes that compose a gas transmission network, attributes include the pipe diameter, its capacity for flow, the date of its last inspection, and perhaps hundreds of other attributes. Similar network structures exist for most of the other utilities mentioned above. The well-developed topological and network data structures that have been integrated into GIS, the network analytical capabilities that are continually being developed, and the underlying relational database management system have combined to make GIS an essential element of utility operations.

Advantages of GIS for Utility Management and Operations

Beyond the clear correspondence between fundamental GIS data structures and utility network systems, GIS holds several other advantages for utility management and operations. Perhaps most important among these is the ability to analyze systems at a wide range of geographic scales. Utilities operate at local or metropolitan (e.g., water and sewer systems), regional (e.g., cable television providers), national (e.g., some telephone systems), international (e.g., natural gas and oil pipeline systems), and even intercontinental (e.g., undersea cable and pipeline systems) scales. At a microscale, GIS can assist with operations within single facilities, and at a macroscale, GIS can assist in global resource planning. The flexibility of a GIS to operate at all these scales allows utility operations to employ spatial technologies throughout their enterprise.

A second advantage of GIS for utility management is the close correlation between traditional GIS data layers and the data needs of utilities. Utilities manage both their own landholdings and the locations of their customers through the use [Page 1316]of cadastral databases. They manage regulatory reporting in part through the use of administrative boundaries (e.g., city, county, state, national). They target markets through the use of both census data and ZIP codes. They plan access to their facilities through the use of street centerlines, and they manage environmental impacts in part through the use of hydrographic, topographic, and land cover data sets. Orthophotography is used increasingly in the planning of new utility construction or expansion.

...