Most concerns about environmental impacts and other risks from leaking natural gas have focused on the fast-expanding production end of America’s vast system of wells, compressors and pipelines. But the urban maze of (often ancient) pipes that carries gas to furnaces and stoves has long been known to be leaking, as well.

Earlier this year, to take a snapshot of this problem, scientists from Boston University and Duke University took equipment that detects methane — the main constituent of natural gas — on a 785-mile van ride through Boston’s streets. The result, published today in the journal Environmental Pollution, is a map showing more than 3,300 spikes in gas concentrations representing leaks of various sizes. [I’ll add a direct link soon.]

via Mapping Gas Leaks from Boston’s Aging Urban Pipes – NYTimes.com.