By Abbas Nazil
California is exploring new regulations to directly reduce methane emissions from dairy and livestock operations, marking a shift from its previous reliance on voluntary grants and incentives.
The California Air Resources Board (CARB) issued a request for feedback as part of its effort to meet the requirements of Senate Bill 1383, a 2016 law mandating a 40% reduction in methane emissions from 2013 levels by 2030.
While rules for methane emissions from organic waste and landfills have been in place for years, dairy and livestock operations were exempt until 2024.
Environmental advocates view the call for information as an opportunity to implement more effective strategies for tracking and reducing methane from the state’s largest agricultural emissions source.
Dairy and livestock operations generate over half of California’s methane emissions, primarily from cow burps and manure. Current programs, combined with declines in animal populations, are projected to reduce emissions by about five million metric tons of carbon dioxide equivalent by 2030, roughly half of the sector’s required reductions to meet the 40% goal.
Much of these reductions come from anaerobic digesters that capture methane from manure lagoons to generate electricity or renewable natural gas. These systems are supported by state funding through the California Department of Food and Agriculture and CARB’s low-carbon fuel standard.
However, critics argue that digesters create incentives for herd expansion, increasing local pollution such as nitrogen, phosphorous, and ammonia. Environmental justice groups have also raised concerns that dairy biogas is over-credited in the state’s carbon accounting, diverting resources from cleaner fuels.
CARB is now beginning the rulemaking process for livestock methane, with public comments due by March 30, aiming to implement regulations that are technologically and economically feasible while preventing farms from relocating to avoid compliance.
Alternative practices, such as separating solid and liquid manure and pasture-based management, are being considered to reduce methane without expanding herd sizes.
California’s rulemaking represents a critical step toward ensuring the state meets its methane reduction targets while balancing economic and environmental considerations, and advocates hope it will realign incentives toward more sustainable dairy practices.
