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Dashboard   >   Emissions and Pollution Control

Emissions and Pollution Control

Overview

Transportation plays a major role in reducing regional greenhouse gas (GHG) emissions. By providing more convenient, efficient and appealing transportation options, we can move more people while reducing the negative impact that transportation has on the climate and public health. We understand the urgency posed by climate change, which is projected to affect our riders and employees, as well as our infrastructure and services. Consequently, each of our actions must be a step toward achieving regional and statewide GHG emissions goals, and ultimately achieving a zero-operational emission transportation system by 2050.

However, the impacts of our transportation system and its operations extend beyond GHG emissions. We operate within the most polluted air basin in the United States, and we recognize that our fuel consumption and use of chemicals (i.e., refrigerants) contribute to regional air quality issues. Accordingly, our approach to mitigating emissions includes strategies that reduce the formulation of smog and other air pollution - which is critical to protecting regional public health. These strategies include transitioning to cleaner fuels and engines and ultimately electrifying our buses and fleet vehicles.

Program Highlights

Seamlessly Integrating Low-Carbon Fuels into Metro Operations
Metro Renewable Diesel Renewable Diesel produces 80% less greenhouse gas emissions than conventional diesel.

In 2024, Metro took a significant step toward decarbonizing our operations by transitioning from traditional red dye diesel to Red Dyed Renewable Diesel (RD99) across our operating divisions. This shift reflects Metro's continued commitment to reducing greenhouse gas (GHG) emissions and supporting California's clean energy transition.

Renewable diesel is a cleaner-burning alternative to petroleum-based diesel. Unlike biodiesel, it is chemically identical to traditional diesel but derived from renewable sources like fats, oils and greases. It consequently produces significantly lower lifecycle emissions of carbon dioxide, particulate matter and nitrogen oxides. The transitioning to RD99 translates to an 80% reduction in GHG emissions compared to conventional diesel, as well as to improved air quality for workers and nearby communities, all while seamlessly integrating with existing engines and infrastructure.

This transition to RD99 supports Metro's broader goals to achieve zero-emissions operations and complements other Metro sustainability initiatives, such as our Green Construction Policy (GCP) and our deployment of electric construction equipment on major projects like the D Line Subway Extension Project.

2030 Targets

Note: In 2020, Metro updated its GHG emissions calculation methodology to calculate Scope 2 emissions using both market-based and location-based emission factors. The former reflects the actual emissions intensity of utility purchased electricity based on the source mix of the procured electricity, while the latter reflects the average emissions intensity of the regional grid on which our energy consumption occurs.

Understanding this Target

This target measures the operational GHG emissions produced by Metro's transit operations and non-modal sources like facilities. Transit emissions are directly associated with moving passengers on Metro trains, buses and vanpool vehicles. Non-modal emissions refer to emissions not directly associated with moving passengers, including emissions from support “non-revenue” vehicles, facility electricity, natural gas consumption, water consumption, refrigerant use and employee commuting. We are implementing several actions to expedite the reduction of our GHG emissions, including the electrification of our bus and vehicle fleet, increasing renewable energy sourcing and storage and improving electricity, water and other facility fixtures. By implementing these and other measures identified in our Climate Action and Adaptation Plan (CAAP) and Moving Beyond Sustainability (MBS) Strategic Plan, Metro expects to achieve a 79% reduction in emissions from 2017 levels by 2030.

Target Performance

As of 2024, Metro has continued to steadily reduce its operational GHG emissions, achieving a 67.9% reduction from the 2017 baseline. While Metro's emissions have slightly rebounded in the last five years since their stark decline from the COVID-19 pandemic, Metro managed to reduce its emissions by 7.2% from 2023. This achievement is largely due to the complete transition from fossil diesel to renewable diesel for Metro's non-revenue vehicles in 2024, as well as the procurement of new electric vehicles for the non-revenue fleet that have replaced older gas-powered vehicles. Metro still has work to do to achieve its 79% reduction by 2030, but given our progress to date, we remain on track to achieving that goal.

1This projected increase in GHG emissions due to bus electrification in the short term reflects the fact that the carbon intensity of the electricity grid today (and likely for a few years to come) is higher than the carbon intensity of using 100% RNG in the bus fleet.
Understanding this Target

This target measures tailpipe NOx emissions from Metro's fleet vehicles, including the directly operated and contracted buses, and the non-revenue and vanpool fleets. Recognizing that reducing criteria air pollutant emissions is critical to protecting public health, we have continued to transition our directly operated fleet engines to near-zero emissions engines, which substantially reduced NOx emissions. We have also committed to completely electrifying our bus fleet by 2030, as well as ramping up electrification across our non-revenue and vanpool fleets. These collective shifts in fleet composition are expected to lower overall NOx emissions by 54% by 2030 from 2018 levels.

Target Performance

Metro has significantly reduced its NOx emissions from the 2018 baseline, far exceeding our initial 2030 commitment. Since 2020, Metro's NOx emissions have declined by over 76%, and our 2024 NOx emissions (33,479 pounds) are about 83% lower than the reduction target (197,425 pounds). These remarkable trends can largely be attributed to the ongoing repowering of bus engines at mid-life, transitioning aging engines to near-zero emission engines that have yielded profound improvements in NOx emissions. The ongoing use of electric buses and newly introduced electric vehicles across our non-revenue fleet are also contributing to this positive impact. As of 2024, Metro is exceeding this target and intends to continue building on this achievement through 2030.

Understanding this Target

This target measures tailpipe PM emissions from Metro's fleet vehicles, including the directly operated and contracted buses, and the non-revenue and vanpool fleets. As with Target 3, initiatives to upgrade engines in our bus fleet and electrify both buses and other vehicles are contributing to ongoing reductions in PM emissions. Altogether, we expect these activities to lower overall PM emissions by 62% by 2030 from 2018 levels.

Target Performance

As of 2024, Metro has reduced its PM emissions by 73.6% from the 2018 baseline, exceeding its original commitment of a 62% reduction. PM emissions have remained fairly level since 2021, which speaks to the impact of engine re-powers and newly introduced electric vehicles across our fleets despite increasing ridership and mileage across the agency. In 2024, Metro did reduce its PM emissions slightly by approximately 0.85% from 2023. As with Target 3, Metro is well on track to continue exceeding this target and build on its success over the next five years.

Overview

Transportation plays a major role in reducing regional greenhouse gas (GHG) emissions. By providing more convenient, efficient and appealing transportation options, we can move more people while reducing the negative impact that transportation has on the climate and public health. We understand the urgency posed by climate change, which is projected to affect our riders and employees, as well as our infrastructure and services. Consequently, each of our actions must be a step toward achieving regional and statewide GHG emissions goals, and ultimately achieving a zero-operational emission transportation system by 2050.

However, the impacts of our transportation system and its operations extend beyond GHG emissions. We operate within the most polluted air basin in the United States, and we recognize that our fuel consumption and use of chemicals (i.e., refrigerants) contribute to regional air quality issues. Accordingly, our approach to mitigating emissions includes strategies that reduce the formulation of smog and other air pollution - which is critical to protecting regional public health. These strategies include transitioning to cleaner fuels and engines and ultimately electrifying our buses and fleet vehicles.

Program Highlights

Seamlessly Integrating Low-Carbon Fuels into Metro Operations
Metro Renewable Diesel Renewable Diesel produces 80% less greenhouse gas emissions than conventional diesel.

In 2024, Metro took a significant step toward decarbonizing our operations by transitioning from traditional red dye diesel to Red Dyed Renewable Diesel (RD99) across our operating divisions. This shift reflects Metro's continued commitment to reducing greenhouse gas (GHG) emissions and supporting California's clean energy transition.

Renewable diesel is a cleaner-burning alternative to petroleum-based diesel. Unlike biodiesel, it is chemically identical to traditional diesel but derived from renewable sources like fats, oils and greases. It consequently produces significantly lower lifecycle emissions of carbon dioxide, particulate matter and nitrogen oxides. The transitioning to RD99 translates to an 80% reduction in GHG emissions compared to conventional diesel, as well as to improved air quality for workers and nearby communities, all while seamlessly integrating with existing engines and infrastructure.

This transition to RD99 supports Metro's broader goals to achieve zero-emissions operations and complements other Metro sustainability initiatives, such as our Green Construction Policy (GCP) and our deployment of electric construction equipment on major projects like the D Line Subway Extension Project.

2030 Targets

Note: In 2020, Metro updated its GHG emissions calculation methodology to calculate Scope 2 emissions using both market-based and location-based emission factors. The former reflects the actual emissions intensity of utility purchased electricity based on the source mix of the procured electricity, while the latter reflects the average emissions intensity of the regional grid on which our energy consumption occurs.

Understanding this Target

This target measures the operational GHG emissions produced by Metro's transit operations and non-modal sources like facilities. Transit emissions are directly associated with moving passengers on Metro trains, buses and vanpool vehicles. Non-modal emissions refer to emissions not directly associated with moving passengers, including emissions from support “non-revenue” vehicles, facility electricity, natural gas consumption, water consumption, refrigerant use and employee commuting. We are implementing several actions to expedite the reduction of our GHG emissions, including the electrification of our bus and vehicle fleet, increasing renewable energy sourcing and storage and improving electricity, water and other facility fixtures. By implementing these and other measures identified in our Climate Action and Adaptation Plan (CAAP) and Moving Beyond Sustainability (MBS) Strategic Plan, Metro expects to achieve a 79% reduction in emissions from 2017 levels by 2030.

Target Performance

As of 2024, Metro has continued to steadily reduce its operational GHG emissions, achieving a 67.9% reduction from the 2017 baseline. While Metro's emissions have slightly rebounded in the last five years since their stark decline from the COVID-19 pandemic, Metro managed to reduce its emissions by 7.2% from 2023. This achievement is largely due to the complete transition from fossil diesel to renewable diesel for Metro's non-revenue vehicles in 2024, as well as the procurement of new electric vehicles for the non-revenue fleet that have replaced older gas-powered vehicles. Metro still has work to do to achieve its 79% reduction by 2030, but given our progress to date, we remain on track to achieving that goal.

1This projected increase in GHG emissions due to bus electrification in the short term reflects the fact that the carbon intensity of the electricity grid today (and likely for a few years to come) is higher than the carbon intensity of using 100% RNG in the bus fleet.
Understanding this Target

This target measures tailpipe NOx emissions from Metro's fleet vehicles, including the directly operated and contracted buses, and the non-revenue and vanpool fleets. Recognizing that reducing criteria air pollutant emissions is critical to protecting public health, we have continued to transition our directly operated fleet engines to near-zero emissions engines, which substantially reduced NOx emissions. We have also committed to completely electrifying our bus fleet by 2030, as well as ramping up electrification across our non-revenue and vanpool fleets. These collective shifts in fleet composition are expected to lower overall NOx emissions by 54% by 2030 from 2018 levels.

Target Performance

Metro has significantly reduced its NOx emissions from the 2018 baseline, far exceeding our initial 2030 commitment. Since 2020, Metro's NOx emissions have declined by over 76%, and our 2024 NOx emissions (33,479 pounds) are about 83% lower than the reduction target (197,425 pounds). These remarkable trends can largely be attributed to the ongoing repowering of bus engines at mid-life, transitioning aging engines to near-zero emission engines that have yielded profound improvements in NOx emissions. The ongoing use of electric buses and newly introduced electric vehicles across our non-revenue fleet are also contributing to this positive impact. As of 2024, Metro is exceeding this target and intends to continue building on this achievement through 2030.

Understanding this Target

This target measures tailpipe PM emissions from Metro's fleet vehicles, including the directly operated and contracted buses, and the non-revenue and vanpool fleets. As with Target 3, initiatives to upgrade engines in our bus fleet and electrify both buses and other vehicles are contributing to ongoing reductions in PM emissions. Altogether, we expect these activities to lower overall PM emissions by 62% by 2030 from 2018 levels.

Target Performance

As of 2024, Metro has reduced its PM emissions by 73.6% from the 2018 baseline, exceeding its original commitment of a 62% reduction. PM emissions have remained fairly level since 2021, which speaks to the impact of engine re-powers and newly introduced electric vehicles across our fleets despite increasing ridership and mileage across the agency. In 2024, Metro did reduce its PM emissions slightly by approximately 0.85% from 2023. As with Target 3, Metro is well on track to continue exceeding this target and build on its success over the next five years.