Annual Gas Distribution Survey

Annual Gas Distribution Survey
February 2011, Vol. 66 No. 2

A sizeable number of the recipients cited the following as contributing to the increased costs: Documentation and record keeping and the requirement for Excess Flow Valves (on all new and replaced service lines serving single family residents if practical), which was cited as adding cost to service.

A gas utility in Florida sees the integrity management legislation as creating a need for additional tracking and reporting burdens and associated costs to document actions. The respondent also indicated that the additional cost to comply with a standardized government format, for most companies, would far exceed any benefits.

With older systems blamed for several recent explosions, companies say they are continuing with long-term programs to replace unprotected steel service lines installed in the 1960s, 70s and 80s.

Atmos Energy has been replacing the steel service lines in its Mid-Tex Division since it acquired the gas distribution system from TXU Corp. in 2004. In July 2010, the company reported it had 57 contract crews dedicated to doing this work and replacing, on average, 500 steel service lines a week. The steel service lines are being replaced with polyethylene lines and are joined with modern fusing technology.

According to the company, the Mid-Tex Division replacement program typifies the preventive maintenance and continual renewal that Atmos has carried out on its gas distribution system in all 12 states in which they operate. The company has reportedly completed, or has under way, similar pipe replacement programs in other states they serve.

As to survey results, 66 percent of survey indicated they have replacement programs in progress while 16 percent indicated they had no cast iron or unprotected steel in existing system. Of the 15 percent reporting bare steel in existing system, the following was the most cited as the risk assessment used to select main and service lines for replacement each year: leak history, pipe materials, maintenance history and location. Only 3 percent of this year’s respondents indicated they had not yet started a long-term program to replace bare steel and cast iron in existing systems.

Respondents reporting on the use of contractors indicate that contractors continue to provide a major portion of new distribution construction to install gas utilities. Although about 10 percent of those reporting indicated they did not rely on contactors at all, approximately 80 percent rely on contractors to carry out 85 – 100 percent of all new construction on projects, while 10 percent rely on contractors to perform 20 to 73 percent of this work.