The views are nothing short of sublime from the decks of almost any of the Seattle metro area’s ferries. Passengers glide by the jagged silhouettes of the Olympic Mountains and past the peaks of Mounts Hood and Rainier looming above Puget Sound. The beauty of the ride “never gets old,” says Jessica Dubey, who has been bike-to-boat commuting for 16 years on the ferry from Bainbridge Island to Seattle. “Sitting outside is so peaceful—the air and the sounds and the scenery,” she says.

Yet not all seats are created equal. Dubey and other locals know to avoid the back of the boats, where smokestacks belch exhaust into the air. The diesel-powered engines take a heavy toll on both passengers’ lungs and the surrounding environment: the Washington State Department of Transportation (WSDOT) ferries account for more than half of the air pollution generated by harbor vessels in Puget Sound, according to the state’s Department of Ecology.

If all goes according to plan, that stat will soon take a nosedive. Some of the biggest boats in the fleet—whose 23 vessels make it the country’s largest ferry fleet, considered part of the state highway system—will be going electric beginning in 2021. The change comes as Washington begins to implement its recently finalized Volkswagen Beneficiary Mitigation Plan, which divvies up the funds received from the auto company’s diesel scandal. As long as the state legislature passes the funding in January 2019, the ferry electrification project will receive about $117 million in support.

As soon as the ferries are converted, air quality will improve. “Diesel pollution poses a triple threat to the health of the communities that are exposed to it,” says Max Baumhefner, a senior attorney at NRDC who focuses on electrifying the nation’s transportation sector. “First there’s direct toxicity, then there’s diesel’s contribution to regional air quality problems and global climate change, which in turn exacerbates local air quality issues,” State officials estimate that repowering ferries can annually eliminate up to 30 tons of smog-producing carbon dioxide pollution per engine.

Stop Climate Change, Save Lives Learn More

It’s not just daily commuters who will benefit from the upgrade to their rides between Seattle and Bainbridge Island, Bremerton, Vashon Island, and the San Juan Islands, among other routes. In the summer, domestic and international visitors double the ridership on some routes. And year-round, the ferries are essential transportation, an integral conduit for local commerce, emergency vehicles, and much more.

Riders will see a phased transition in the ferry fleet: First, three of the largest ferries in the system will be converted to run on a combination of battery-stored electric power and diesel. The boats will eventually go all-electric, but first charging stations need to be built, which will take additional time, says Max von Ruden, director of vessel engineering and maintenance for the WSDOT Ferries Division. In the interim, a 25 percent reduction in these vessels’ diesel fuel use will kick in beginning in 2021. As soon as plugs are installed at each ferry port (planned by 2023), they will be able to run fully on electric power.

“The battery technology is becoming widespread,” says von Ruden, citing the 30-plus ferries in Norway, Denmark, and Sweden that are in the process of being converted to electric-only power. The Tycho Brahe and Aurora, which operate between Denmark and Sweden, have been running on electricity since 2015. By 2023, Norway’s entire ferry fleet will be all-electric, and other countries, including China, are looking to make the same changes to their cargo ships, too. “This is not new or high-risk technology,” von Ruden says.

Ferries aren’t the only big diesel fuel users getting an electric upgrade in coming years. “Because battery prices have declined 80 percent between 2010 and 2017, now we can start electrifying truck, buses, cranes, forklifts, boats, and other, bigger things that are the primary source of dangerous diesel pollution,” says Baumhefner. “That’s happened sooner than anyone thought would be possible.”

These projects aren’t only good for the environment—they’re also a boon to the economy. In Seattle, the once the ferries are running on full electric power, they’ll use 90 percent less fuel than what the current fleet consumes. That means “significant” savings for WSDOT, notes von Ruden, who adds that “initial studies show a projected life-cycle savings of $60 million.” Electrification will also remove some of the uncertainty in the department’s ferry budgets. “Fuel fluctuates in price, and when fuel costs go up it really impacts us,” he adds. In years with high diesel prices, important maintenance and improvement projects have had to be delayed because there wasn’t enough money to balance budgets. Electricity is significantly less volatile in terms of cost, especially since Washington produces so much of it from hydropower.

Puget Sound’s marine life—including its beleaguered orcas—will also benefit from the electric ferries. In 2013, University of Washington researchers studying the soundscape in parts of these waterways found that at least one big, noisy vessel—a container ship, ferryboat, or tug—was traversing the area’s busy shipping lanes at least 90 percent of the time. Like a hybrid car, the electric ferries will be much quieter, reducing the man-made noise that can drown out the sounds marine mammals rely on for foraging, communicating, and other vital functions. Engine sounds, like those produced by large ferries, can make echolocation more difficult for animals that use sound to locate food.

Stop the assault on whales, dolphins, and other marine mammals Take Action

This combination of powerful reasons to go electric was “such a compelling case that the legislature funded us to move forward on the design” of the new ferries, says von Ruden. That design was delivered in late October.

In addition to converting existing ferries to run on electric power, WSDOT has plans to introduce five new ferries—all hybrids—to meet an expected 30 percent increase in ridership over the next 20 years. Sixteen additional new hybrid vessels will be added by 2040 to replace some of the older ships, which have already been in use for nearly 50 years.

Seattle’s piloting of the ferry electrification project may well inspire other cities to follow suit. The San Francisco Bay Area recently unveiled its first plug-in hybrid ferry, a move that will likely be followed by further efforts to upgrade its fleet. The Staten Island ferries in New York and ferries between Long Island and Connecticut could also be candidates for electrification.

Meanwhile, the commuters of Puget Sound are eagerly awaiting the transition. Bike-to-ferry commuter Karl Fritzche was pleasantly surprised by the speed at which the project is set to move forward. “The ferries are cool, and iconic for the area, and it’s nice to see them on the sound,” he says, “but then you see this excess exhaust going into the air and it takes away from that. Switching over to electric power is the right step forward for sure.”