Photo: Liz Hafalia / The Chronicle Photo: Carlos Avila Gonzalez / The Chronicle

With Market Street purged of cars, San Francisco Mayor London Breed now seeks to unclog the surrounding arteries and curbs. Her solutions would require drivers to open their wallets.

For some, a little relief may be worth a price. Downtown traffic is intolerable: cars, ambulances, Muni buses and delivery trucks get stranded in jams so bad, it can take 45 minutes to move a block and a half. Packages are late, cyclists jostle among angry drivers, and pedestrians get cut off by vehicles that barrel through intersections. Motorists orbit the blocks to find parking.

As the city’s economy booms, the streets will only get more choked.

Breed is pressing for two controversial measures to alleviate the crush of downtown traffic. One is congestion pricing — tolls to drive on the busiest roads at peak times. The other is Sunday and evening parking meters.

“San Francisco needs to be bold as we rethink and invest in our transportation infrastructure,” the mayor wrote in a letter to the San Francisco Municipal Transportation Agency’s Board of Directors, a draft of which was obtained by The Chronicle.

“Our population is growing yet our roads cannot get any wider,” Breed continued, “nor can we add additional curb space for parking.”

City and county transportation officials are already knee deep in discussions about these policies. The San Francisco County Transportation Authority is studying the possibility of charging a fee to drive downtown and through SoMa during rush hour, and its staff expects to release proposals early next year.

The logistical hurdles are daunting. San Francisco would need the state to pass legislation allowing the city to tack fees on the use of public roads.

So far the mayor has offered little information about where the tolls would be enacted, how much they would cost or how much money they would raise. In her letter, she cites SoMa and the downtown core as areas most in need of intervention.

At the same time, the Municipal Transportation Agency is considering ways to free up parking spaces, including a proposal to extend meters until 10 p.m. in some bustling commercial districts. Because parking is free after 6 p.m. on most streets, people swarm in at 6:05 p.m. and stow their cars until the next day.

“On a street like Valencia, it’s just maddening,” said Sharky Laguana, president of the city’s Small Business Commission. “There are a million restaurants and no spaces. You don’t want a busy commercial corridor being used for car storage.”

Sunday metering has been a point of contention for years. The city tried it in 2013, predicting the fees would help parking turnover in front of restaurants, shops and offices, while generating $9 million year from both the meters and Sunday parking tickets. But the SFMTA reversed the policy the following year under pressure from then-Mayor Ed Lee. He said the charges unfairly “nickeled and dimed” his constituents.

Churches and other religious groups were among the most vociferous opponents to Sunday meters, saying people shouldn’t have to run out of a house of worship to pump money into a machine.

“At that time ... the messaging and communication wasn’t great,” said Michael Pappas, executive director of the San Francisco Interfaith Council. Pappas has not taken a position on the current proposals but said he’s open to reasonable dialogue.

To state Sen. Scott Wiener, the backlash isn’t just about cost. Policies that charge people to drive upend a deeply ingrained worldview, he said.

“People are used to everything being free when they drive,” said Wiener, a San Francisco Democrat who served as a supervisor during San Franciso’s last Sunday meter experiment. He noted that California, like other states, has “subsidized driving massively” — gas taxes and vehicle registration fees don’t cover the cost of maintaining road infrastructure.

Strategies like Sunday or evening parking meters and road tolls seek to lure people out of cars, and many motorists don’t want to change their habits, Wiener said. Politicians are reticent, as well. When Wiener co-wrote a bill two years ago to allow four California cities to test congestion pricing, it didn’t pass a single committee.

Yet attitudes appear to be shifting in San Francisco, particularly among leaders in City Hall. Last year, Breed directed the Municipal Transportation Agency to accelerate its production of protected bike lanes — paths enclosed with posts or barriers that take space away from cars. The mayor also appointed a new transportation chief, who has promised “institutional change” — namely, a city where the automobile is no longer king.

Laguana, of the Small Business Commission, said he welcomes the mayor’s ideas for traffic management. Like other merchants, he’s frustrated by the traffic misery and the scarcity of parking. Laguana owns a van rental company on Potrero Hill, but he often goes downtown to run errands. What should be an easy trip becomes a frustrating exercise in sitting and waiting, he said.

He believes that a smoother flow of traffic and churn of parking spaces would help small businesses. But Laguana also shares Breed’s goal, which is to nudge people onto public transit. The mayor said in her letter that any revenue harvested from these policies should be invested in subway expansion and transit service.

“This will get anybody going downtown to think about when they’re going and when they’re leaving, and it might disincentivize cars, which is a good policy goal in general,” Laguana said.

Among the people he’d like to convert is his wife, a makeup artist who works in downtown department stores. She drives their kids to school and then continues on to work, spending a chunk of her day in a glacial, stop-and-go commute.

If that drive includes a toll, Laguana mused, then maybe the bus will look more appealing.

Rachel Swan is a San Francisco Chronicle staff writer. Email: rswan@sfchronicle.com Twitter: @rachelswan