Pipelines
Pipelines provide a vi
tal transportation service. Approximately half of the nation’s supplies of crude oil and petroleum products and virtually all of its natural gas supplies are transported through a network of 1.7 million miles of pipelines.
The materials carried by pipelines are flammable, explosive, or toxic, which means that pipelines pose a danger to people and property should their failure result in release of these materials to the environment. The development of residences, workplaces, and shopping areas near once-isolated transmission pipelines, which carry gas and liquids at high pressure from producing areas to refineries or distribution networks, threatens to increase the risk of pipeline failure due to inadvertent excavation damage. Historically, such excavations have been a major cause of pipeline accidents. Accidents in the future could also be more severe because new development has exposed more people and property to risk in the event of a failure.
Pipeline safety was addressed initially by a TRB committee in 1998, many of whose recommendations were adopted by government and industry after release of the committee’s report (Special Report 219: Pipelines and Public Safety; TRB 1988). The recommended measures include collaboration on damage prevention and public awareness programs, land use measures, and emergency preparedness programs. The committee stopped short of recommending specific development setbacks that would provide more uniform land use control across the nation. Instead, it pointed out a number of procedural changes in land development review and regulation that would reduce the risk of inadvertent damage. Although more uniform public policies on land use near pipelines might be desirable, differences in local conditions argue against establishing definitive standards or limits on specific land uses near pipeline rights-of-way.
A second committee was convened in 2004 to addresses the risk of population encroachment around transmission pipelines (Special Report 281: Transmission Pipelines and Land Use; TRB 2004). Projected increased demand for natural gas and petroleum products shipped by pipeline indicates that many more miles of transmission pipelines—much of it in areas with high population growth—will be required. Fortunately, pipelines are the safest mode for moving such volatile materials. Even so, and although fatal accidents are rare, incidents occur almost daily.
The second committee assessed the feasibility of developing risk-informed guidance that state and local governments could use to manage land development near transmission pipelines. Although the data needed to develop such guidance are imperfect, the committee’s report concluded that it is feasible to develop risk-informed estimates, which would vary by type of pipeline, product carried, and other dimensions. The committee urged the USDOT Office of Pipeline Safety to work with stakeholders and risk-assessment experts to develop such guidance. This guidance should address the siting and width of new pipeline corridors, the range of uses compatible with pipeline rights-of-way, development setbacks and other measures, and model zoning ordinances. It should be sufficiently flexible that local governments and states could tailor their responses to account for local conditions.