There are three basic types of natural gas pipelines. "Gathering" pipelines carry natural gas from production wells. "Transmission" pipelines transport natural gas across the country. And, "distribution" pipelines carry natural gas to homes and businesses.
U.S. Department of Transportation, Pipeline and Hazardous Materials Safety Administration (PHMSA) data shows an average 155 incidents happen annually related to distribution pipelines. In 2009, there were 158 natural-gas distribution pipeline incidents reported to PHMSA that killed 10 people, injured 50 and caused almost $32 million in property damage.