Air quality in Torrance

How is the air quality in Torrance, CA?

The city of Torrance is located in the southwestern region of Los Angeles County, about 20 miles from the city of Los Angeles. It’s a coastal city with a 40-acre beach neighboring Redondo Beach and Malaga Cove, with a population of roughly 145,000 over an area of about 21 square miles. The city’s geographic location and its proximity to emissions sources, such as local refineries and the ports of Long Beach and Los Angeles, affect the region’s air quality. Cold air blowing in from the coast frequently traps emissions from local traffic, the ports, and the refinery in the L.A. Basin, where pollution can stagnate for days at a time.

The average air quality index (AQI) in Torrance is 42, considered “good” by US Environmental Protection Agency (EPA) standards. Fine particulate matter, or PM2.5, is often the “main pollutant” that determines Torrance’s overall AQI due to its prevalence and relatively high risk to health. In 2019, annual PM2.5 levels in Torrance were 11.6 μg/m³, just barely meeting federal targets set at 12 μg/m³ but exceeding the more stringent World Health Organization target set at 10 μg/m³.

Air quality concerns in Torrance gained public attention after an explosion on February 18, 2015 at the Torrance Refinery (owned by ExxonMobil at the time). The accident (caused by pent-up gases) triggered a massive eruption, which registered as a magnitude 1.7 tremor.¹ Ash and soot rained over an area of about a mile of area, while gases and fine particulates were emitted over a much wider area. The initial shock was so strong it caused a 40-ton piece of equipment to fly into the air. The disaster could have been worse, however. The explosion narrowly missed hitting a tank containing tens of thousands of pounds of hydrofluoric acid (HF), an extremely toxic gas capable of corroding bone. The refinery has since increased safety measures to prevent future accidents.

Since the Torrance Refinery explosion in 2015, wildfires have dominated headlines as the most frequent severe air pollution event. Although Torrance is urban, wildfire smoke frequently blows in from the hills surrounding Los Angeles County, Long Beach County and Orange County. The 2020 Silverado Fire, for example, caused elevated pollution levels for days at a time.

According to the American Lung Association (ALA) State of the Air report, Los Angeles County, of which Torrance is a part, has never met federal attainment levels for ozone and PM2.5 pollution. On average, the region experiences 124.8 unhealthy air quality days a year, 111 of which are attributed to ozone pollution and 13.8 of which are attributed to PM2.5 pollution.² For reference, Los Angeles County would need to reduce the frequency of unhealthy PM2.5 and ozone days to no more than 3.2 days per year in order to meet EPA targets.

With roughly one in every three days deemed “unhealthy” to breathe, it may be of little surprise that the region ranks among the worst in the United States for key pollution metrics:

• #1 for high ozone days out of 229 evaluated metropolitan areas
• #6 for high particle pollution days out of 216 evaluated metropolitan areas
• #4 for annual particle pollution out of 204 evaluated metropolitan areas

Why is Torrance, California so polluted?

Torrance’s air pollution comes from a combination of emission sources, including:

• gas-powered motor vehicles (cars, trucks, and heavy duty equipment)
• industrial activity
• the Torrance Refining Company
• Port of Los Angeles and the Port of Long Beach
• domestic wood burning and barbecuing
• nearby wildfires

While vehicular traffic represents the leading cause of city-wide emissions, many are quick to point to the Torrance Refining Company as a major source of industrial emissions. While the Torrance Refining Company has set a SO_x emission target at 54,800 pounds, it has never met this goal.³ In 2018, the refinery recorded releases of 323,546.4 pounds, nearly 6 times the target. More recently, in 2019, the refinery released 124,826.9 pounds through June 30.

Torrance’s location near the Port of Los Angeles and the Port of Long Beach represents another significant emission source. Trucks traveling to and from the ports as well as exhaust from trains and ships sharply increase the amount of ambient PM2.5 and ozone precursor pollutants (nitrogen dioxide and volatile organic compounds). When sunlight is abundant and temperatures are warm (conditions common in Torrance), these ozone precursors form ground-level ozone, a key component of smog.

When is Torrance air quality the best?

Late winter and spring tend to be the best months for air quality in Torrance. Cooler temperatures and increased rain during this period allow emissions from local traffic, the ports, and the refinery to be tamped down and washed away. Meanwhile, lower temperatures prevent ozone formation by depriving ambient precursor pollutants the heat they need to react. These combined effects produce a lower average AQI in Torrance than that of the summer and fall seasons.

Climate change has resulted in warmer months on average in recent years. This effect has had a direct correlation to the increased frequency of wildfires in the area, which have had devastating effects on the air quality of the region. Wildfire season in California runs from July through November. During these months, unpredictable and usually short-lived wildfires can cause temporary but significant spikes in pollution levels.

Daily commutes affect the hourly AQI rating in Torrance. Early mornings before rush hour and late evenings tend to have better air quality as a result of fewer cars and trucks on the road.

How much pollution in Torrance comes from the Port of Long Beach?

The Port of Long Beach is the second busiest port in the United States behind the Port of Los Angeles.⁴ Each year, the Port of Long Beach handles more than 7.6 million 20-foot container units (78.5 million metric tons), with cargo valued at approximately $170 billion. The ports account for about 1/3 of all loaded containers moving through California ports, with 1/4 moving through West Coast ports and about 20 percent moving through U.S. ports.

The ports of Los Angeles and Long Beach together emit 100 tons of smog daily.⁵ Diesel trucks traveling to and from the ports, as well as exhaust from ships, trains and cargo-handling equipment all emit deadly particulate matter into the air that reduces visibility.

On October 5, 2020, a new 6-lane bridge opened to traffic, replacing the 52-year-old Gerald Desmond Bridge.⁶ The old bridge needed repairs and was considered too narrow and too low to meet the needs of current cargo traffic. The Gerald Desmond Bridge carries about 15 percent of the nation’s imported container cargo. The 6-lane bridge allows for more traffic flow and less congestion into the Port of Long Beach. Increased use of the bridge, however, may result in increased vehicular emissions. It is yet to be seen how this will affect net emissions in the area.

What is being done to improve air quality in Torrance?

State officials are working to combat the possible negative effects of air pollution produced by traffic flowing to and from the ports through the implementation of the San Pedro Bay Ports Clean Air Action Plan (CAAP) in 2006.⁷ The plan features strategies for both the Port of Los Angeles and the Port of Long Beach to significantly reduce pollution without impeding operation, port development, and job creation efforts.

Among action items in the CAAP is the Clean Truck Program, which limits the age of trucks signing up for the Port Drayage Truck Registry (PDTR) to 2014 or newer. Other action items include vessel pollution reduction programs and advancements in port-related technology, including the world’s first hybrid tugboat.

A large focus of the Clean Air Action Plan is to cut the emissions of sulfur oxides (SO_x), nitrogen oxides (NO_x) and diesel particulates. Compared to levels in 2005, joint efforts by the ports have resulted in a reduction of SO_x by 97 percent, NO_x by 48 percent, and particulates by 84 percent.⁸ Additional efforts are being made by the ports to transition to near-zero emission (NZE) and zero-emission (ZE) equipment by 2030 as well as NZE and ZE vehicles by 2035.

An expansive contribution to improved air quality in Torrance came after the 2015 Torrance Refining Company explosion. The South Coast Air Quality Management District (SCAQMD) sponsored the Torrance Air Quality Monitoring and Notification Project (Torrance Air) project, which provides Torrance residents with near real-time information about air pollutant concentrations in and around the community. Prior to the implementation of the project, air quality monitoring for Torrance was largely unavailable. The nearest monitoring stations were in Long Beach, approximately 15 miles away from the Torrance city limit.

The Torrance Air project uses two methods to monitor air quality. The first is an air monitoring system along the northern and southern fence lines of the Torrance Refinery. The second is a series of community-based air quality monitoring stations throughout the city of Torrance.

In addition to creating the Torrance Air monitoring system, SCAQMD is also working with environmentalists to block BNSF Railway’s Southern California International Gateway project from building an intermodal railway in Wilmington adjacent to West Long Beach.⁹ Residents and local officials fear the railyard would exacerbate emissions near homes and schools by adding millions more truck trips per year.

At the federal level, the US Environmental Protection Agency (EPA) has set a 2021 deadline for California to reach acceptable PM2.5 levels, but the state is seeking an extension to 2025 by classifying itself in “serious” rather than “moderate” nonattainment of air quality standards. However, California is making great strides toward improving its air quality. The state passed assembly bills 617 and 134 in 2017, which will provide more than $1 billion in clean vehicle incentives and community air monitoring programs to help cities meet EPA goals. The bills also stipulate that officials must find new ways to reduce PM2.5 emissions and ozone levels below federal standards while also installing community air monitors statewide.

+ Article Resources

[1] Zou JJ (2017, February 15). The ExxonMobil near-disaster you probably haven’t heard of. The Center for Public Integrity.
[2] American Lung Association. (2020). State of the Air – 2020.
[3] Nahigyan P. (2019, May 6). Environmental health hazards impacting the City of Long Beach. Long Beach Business Journal.
[4] Port of Long Beach (2020). Port facts and FAQ’s.
[5] Mazza S. (2018, August 7). Investigation finds LA Harbor-area smog challenges grow as new health threats emerge. University of Southern California Annenberg Center for Health Journalism.
[6] Port of Long Beach (2020) About the Bridge.
[7] Clean Air Action Plan (CAAP). (2020). About the plan.
[8] Clean Air Action Plan (CAAP). (2017, October 23).Plan update fact sheet 10-23-17
[9] Torrance Air. (2020) Torrance air.