Nearly 5,900 natural-gas leaks have been found under the streets of Washington by a research team from Duke, Boston University, and Gas Safety Inc. Some of the leaks could have posed explosion risks, according to the team.
“Repairing these leaks will improve air quality, increase consumer health and safety, and save money,” says Robert B. Jackson, a professor of environmental sciences, who led the study.
The researchers mapped the gas leaks using a high-precision Picarro G2301 Cavity Ring-Down Spectrometer installed in a GPS-equipped car. Laboratory analyses confirmed that the isotopic chemical signatures of the methane and ethane found in the survey closely matched that of pipeline gas. Methane levels in some leaks were as high as 89 parts per million, about forty-five times higher than normal background levels.
Last year, the team discovered 3,300 natural-gas leaks beneath Boston. Like Washington and Boston, many U.S. cities have aging pipeline infrastructure that may be prone to leaks. the researchers recommend coordinated gas-leak mapping campaigns in cities where the infrastructure is deemed to be at risk.
Nationally, natural-gas pipeline failures cause an average of seventeen fatalities, sixty-eight injuries, and $133 million in property damage annually, according to the U.S. Pipeline and Hazardous Materials Safety Administration. Natural gas also contains methane, a powerful greenhouse gas that can catalyze ozone formation. Pipeline leaks are the largest human-caused source of methane in the U.S. and contribute up to $3 billion of lost and unaccounted-for natural gas each year.