It’s not always about vehicles on wheels. California’s ports and harbors are a large source of air pollution too: tugboats, ferries, and excursion vessels that dock in California’s ports and cram our harbors are pumping toxic fumes into our air, dirtying our waterways, and contributing to the climate crises plaguing California.

The dark plumes of smoke from these polluting vessels, which are fueled by dirty diesel fuel, have burdened communities living near ports with rising health and cancer risks for too long. In the South Coast Air Basin, a region with some of the country’s worst air quality, emissions from harbor boats have increased by 40 to 60 percent. In the Ports of Los Angeles and Long Beach, harbor boats are one of the top three contributors to cancer risk from diesel particulate matter exposure—falling only slightly behind container ships and locomotives. And harbor boats are expected to contribute a larger share of pollution in the future as oceangoing vessels and locomotives get cleaner over the next decade.

The California Air Resources Board has an opportunity to address these grim statistics and protect public health by strengthening the existing commercial harbor craft regulation, a well-intentioned but too-weak rule that was first adopted in 2007 to reduce toxic emissions from boats and other harbor vessels. Earthjustice, along with a coalition of dozens of environmental groups, is calling on CARB to make the rule more stringent in this fall’s rulemaking process. We’re asking the Board to:

• Require a 100% zero-emission transition for the majority of harbor boats by 2034/2035, including tugboats and barges, which are excluded from the current rule
• Add language to allow the Board to revisit the rule as the zero-emissions boat market evolves to ensure the regulation achieves more emission reductions
• Increase funding for zero-emissions boat pilots and retrofits to spur innovation

Innovation in the maritime industry is lagging behind other industries in the transportation sector, like passenger vehicles and trucks, largely because regulators haven’t held the shipping and boating industry accountable. Without significant pollution and air quality standards and regulations, we’ve provided manufacturers with little reason to innovate and begin producing cleaner boats. Instead, they’ve been given a free pass to continue with business as usual while frontline communities pay the price with their health.

And though some insist that zero-emissions boats and vessels aren’t ready to hit our harbors, we’ve already seen technological progress. Last month the Port of San Diego announced plans to test the first zero-emissions tugboat, which would replace a diesel-fueled boat that uses over 30,000 gallons of fuel a year. That’s the equivalent of removing 267 metric tons of carbon dioxide from our atmosphere. And that’s from one boat alone.

With new data from the Intergovernmental Panel on Climate Change showing that planet warming is likely to rise around 1.5 degrees Celsius within the next two decades, and with regions in California experiencing some of the worst smog in years, we need urgent action from CARB. By implementing a stronger commercial harbor craft rule, CARB can send a signal to manufacturers that it’s time to invest in zero-emission boat technology and take a significant step in protecting the health of portside communities and our climate.