But bus riders were already enjoying quicker commutes with cars largely cleared out of the way.

“Buses are moving a lot faster,” said Steven Colon, 25, a customer assistant at a grocery store, who commutes to work by bus along 14th Street. “This is a good idea because a lot of people double park and it causes a lot of congestion.”

From now on, drivers are allowed onto 14th Street only to make deliveries and pick up and drop off passengers from 6 a.m. to 10 p.m., seven days a week. They can travel just a block or two before they have to turn right off the street. No left turns are allowed. The police will give out warnings at first and surveillance cameras will be watching.

The new rules made for a remarkable scene: a major Manhattan street devoid of cars looking more like a lonely rural stretch.

“It’s not that cars are losing ground, it’s that New Yorkers are gaining ground, literally,” said Danny Pearlstein, a spokesman for the Riders Alliance, an advocacy group for transit riders. “We make the city what it is. Cars get in the way."

City transportation officials said it would take time for people to get used to the new traffic rules, and noted that on rainy days, traffic usually slowed anyway.

“It’s Day 1,” said Polly Trottenberg, the city’s transportation commissioner. “We ask for everyone’s patience.”

City officials had prepared for the busway by holding neighborhood meetings, working with local elected officials and community boards, and reaching out to navigational apps such as Waze to keep drivers away from 14th Street. In recent days, they also went door to door on 14th Street handing out fliers, made press announcements and took to social media to remind everyone about the new car restrictions.