Quantifying methane emissions from orphan oil and gas wells in Canada

Non-producing oil and gas wells are a source of fugitive methane emissions. In Canada, methane regulations for the oil and gas sector are pushing the industry to achieve a 72% reduction in methane emissions by 2030 compared to 2012 levels. To reach this goal, effective monitoring and remediation of non-producing wells is important, as there are >400,000 non-producing wells in the country and they account for 13% of methane emissions from the oil and gas sector. Orphan wells are a subset of non-producing wells that have no responsible party, as such the cost of clean-up falls on the public. Thus far, there have been no quantification studies on methane emissions from orphan wells in Canada, leading to knowledge gaps for policy development and contributes to uncertainties in methane emissions from the broader category of non-producing wells.

To fill this gap, we performed an orphan well specific methane measurement campaign in Western Canada during the summer of 2025. We followed a static chamber methodology paired with laser-based methane sensors with detection capabilities in the ppb scale, an approach that was previously deployed at 561 non-orphan wells across Canada. This method allowed for direct component-specific methane flow rate measurements with detection as low as 10^-3 mg/hr. We measured methane emissions from 143 individual orphan wells across 16 different counties in two Western Canadian provinces where 75% of non-producing and 65% of orphaned wells in Canada are located (Alberta and British Columbia).

Previous literature showed that a small subset of wells dominates emissions, highlighting the need for a faster, larger-scale detection method. While the static chamber approach provides direct component-specific measurements, it is time- and labor-intensive and limited to wells where site-access is possible. To address this, we deployed a helicopter-mounted light detection and ranging (LiDAR) system enabling rapid identification of high-emitting orphan wells. With this method, we surveyed 180 orphan wells, including those in extremely remote locations that are inaccessible by ground vehicle, or limited to winter-only access.

By integrating both ground- and helicopter-measurements, we aim to improve quantification of methane emissions from orphan wells in Canada and deliver a roadmap for prioritizing remediation efforts to effectively reduce national methane emissions.