Mayor Jenny Durkan released her proposed 2019-2020 budget on Monday, and there are a lot of headlines there on homelessness spending (more permanent funding, but not a huge increase in overall funding), policing (an additional 40 officers), and job cuts (150 fewer jobs across departments). But Durkan also signaled a continued commitment to an idea she first floated during her campaign: congestion pricing, or targeted tolls to reduce car traffic on city streets.

Durkan did not specifically mention the proposal in her speech detailing the budget on Monday. If implemented, Seattle could be the first United States city to have such a program.

Back in April, Durkan announced a slate of action items that included congestion pricing to help the city combat climate change. At the time, the tolling plan—“improving mobility through pricing”—was vague: The document says the plan will combine pricing to drive on certain streets with expanded investment in “transit and electrification in underserved communities.”

As part of the package, Durkan said Seattle Department of Transportation (SDOT) would conduct a study to look into what this could look like in Seattle, including possible pricing plans, and examine how a system would affect congestion from State Route 99 tunnel tolling, a growing population, ride-hailing, and freight vehicles.

In the budget, the mayor’s office acknowledges that SDOT has already “started work to assess the potential benefits of establishing a congestion pricing program” and adds $1 million to the budget to “support the second phase of this work.”

“Congestion pricing can be an effective strategy for reducing greenhouse gas emissions and improving mobility,” reads the budget section.

While a program like this hasn’t been implemented yet in the United States, we’re not the first U.S. city to have this conversation—and similar programs have seen success in Europe. In 2003, London started congestion pricing in many of its central neighborhoods, charging around $15 USD to drive a vehicle through between 7 a.m. and 6 p.m. The program raised around $1.6 billion USD in the first 10 years. That money has gone toward mobility improvements that don’t rely on single-occupancy vehicles, including the city’s bus network and bike infrastructure. Other cities have gone so far as to ban certain types of vehicles from downtown streets altogether.

Still, the issue is bound to bring up questions of the tolls’ impact on the poor; Seattle has one of the most regressive tax structures in the country, and flat-rate tolls have a disproportionate impact on people with lower incomes. Proponents of congestion pricing argue that free roads have a disproportionate benefit to the wealthy.

“Free roads function like a matching grant for drivers: the more money people can invest in driving, the more benefit they get from unpriced streets,” UCLA urban planning professor Michael Manville told KUOW back in April. “If, conversely, you can’t afford to drive at all, free roads don’t help you.”

Fuel savings also factor into Durkan’s budget, which comes at the same time as an executive order to reduce 10 percent of the city’s car fleet. “We found that we are spending way too much [on fuel],” said Durkan during her budget address, “so we cut it.”

Durkan proposes funding more bus service hours and a greater investment in “micro-transit” to ”support and increase mobility in areas where there are service gaps.” The budget also doesn’t call time of death on the downtown Center City Connector streetcar project, which the mayor’s office put on the chopping block earlier this year.

Other budget items proposed to reduce car congestion includes addressing “block-the-box” incidents, where vehicles don’t leave an intersection clear, keeping other cars from crossing an intersection, blocking emergency vehicles, and escalating unsafe conditions for pedestrians and cyclists. Seattle would lobby the State Legislature to clear the way for enforcement.

But while Durkan’s budget seems to prioritize clearing cars and making more room for transit, it also proposes cuts to programs that open streets up to non-car uses—and don’t cost much.

Under the budget proposal, both the Pavement to Parks and Play Streets programs would be cut. Pavement to Parks takes underutilized streets and turns them into permanent, or at least long-term, parks—like the park with the Pac-Man design on Capitol Hill. Play Streets temporarily blocks off traffic for community events. The cost for both programs is minimal on a city budget scale (Durkan’s whole budget is $5.9 billion): The Play Streets cut adds up to $183,975, and the Pavement to Parks cut saves $285,600.