Wearing a reflective orange jacket over his suit, Mayor Bill de Blasio celebrated spring, the start of construction season, by announcing street safety redesigns planned in each borough this year — from “Mott Haven to Marine Park,” he said.

Those projects, ranging from the installation of a wide bike-friendly promenade on Tillary Street’s approach to the Brooklyn Bridge to the city’s first “neighborhood” traffic circles on Staten Island, will break ground or progress through community boards during a high note for the mayor’s Vision Zero program: Traffic deaths are continuing to decline.

Deaths on city streets have dropped by 20%, from 48 to 40, when comparing data through March 20 of this year to the same period in 2016. And traffic enforcement is up, to aid the Vision Zero initiative’s goal of eliminating all traffic deaths.

“We understood that Vision Zero had to be aggressive … to stop the kinds of things that are putting lives in danger,” de Blasio said. “And we know it’s working. We have now three years to look at and we’ve seen constant progress. … Each year under Vision Zero has been safer than the one before.”

NYPD enforcement against drivers who speed; don’t yield to pedestrians; and block bike lanes increased between 17% and 29%, depending on the violation, through March 20.

“I’m very impressed, very pleased with the scope of the projects discussed today,” said Steve Hindy, a member of Families for Safe Streets (FSS), a branch of the advocacy group Transportation Alternatives, who spoke at the news conference. “I think it’s great that there are things happening in all the boroughs.”

That’s a very different tone from advocates who just this summer rallied for the mayor to treat Vision Zero as more than a “feel-good slogan.” Cycling deaths had increased in 2016, despite an overall drop among all types of travelers. Groups like FSS and Transportation Alternatives charged the mayor with neglecting one of his major campaign platforms.

In de Blasio’s January budget presentation, he proposed an additional $400 million to be spread out over six years for street safety projects, bringing total Vision Zero funding to $1.6 billion.

“This is the kind of equipment we were hoping for,” Hindy continued. “You know, you always want more, but you have to give credit where credit is due. And I think this is a pretty comprehensive and significant step forward.”

The mayor on Tuesday highlighted 16 top projects coming this year, geared toward either curbing speeding, building bike infrastructure or granting more space to walkers. High-profile street redesigns include a parking-protected bike lane on Brooklyn’s Fourth Avenue and the city’s plan to adjust parking on Manhattan’s Fifth Avenue to create a protected bike lane there.

De Blasio’s next challenge will be taking on Albany over state legislation allowing the expansion of the city’s speed camera program. Currently, there are 140 locations with cameras; they must be within a quarter mile of a school entrance and only operating during school hours. The city cannot legally exceed that number.

Over the past five years, about 85% of traffic fatalities and serious injuries happened in times and places where the city can’t use those cameras, according to Polly Trottenberg, the commissioner of the city’s Department of Transportation

“So even just lifting those restrictions would be tremendously important,” Trottenberg said.

There have been 15,497 NYPD summonses issued for drivers blocking bike lanes through March 20, a 23% increase compared to that time last year, according to Thomas Chan, the NYPD’s chief of transportation.

But the mayor still needs to overcome the perception that drivers of municipal vehicles, particularly NYPD officers, don’t care about Vision Zero’s tenets, as documented by advocates like the Twitter user @CopsInBikeLanes.

Chan said that his team targets the precincts of vehicles that are photographed blocking bike lanes.

“At my forum, at TrafficStat, we bring the boroughs and the individual precincts who are present and we actually show the photo of the department vehicles that are in those bike lanes,” Chan said, “and we encourage our officers not to park their vehicles in those particular lanes.”

Precinct commanders are advised to take note of officers’ parking behavior. After warnings, commanders have the discretion to deduct hours from officers caught blocking bike lanes in non-emergency situations.