First study of NYC congestion zone’s air quality impact shows improvements

The study also examined air quality around freeways which experts worried would see increased traffic from people avoiding the tolls.

1 minute read

August 21, 2026, 8:00 AM PDT

By Zachary Whalen

A graph from New York City's first study on the Congestion Relief Zone Tolling Program’s impact on air quality. The graph shows that air quality improved at the rate predicted, and in some cases, slightly more than predicted.

A graph from the New York City Health Department’s study of the Congestion Relief Zone Tolling Program’s impact on air quality. | New York City Health Department

On Aug. 14, the New York City Health Department released its first study of the Congestion Relief Zone Tolling Program’s impact on air quality. After a year of congestion pricing, the evaluation found that the air quality of the neighborhoods within the Congestion Relief Zone either improved slightly or stayed the same, Noah Kolenda writes for Mass Transit. The report also revealed that congestion pricing led to more people choosing to walk, take transit or bike into congestion zones.

The report also studied the air quality of communities near major highways, including the Brooklyn-Queens Expressway and Trans-Manhattan Expressway. The Congestion Relief Zone Tolling Environmental Assessment had warned that these neighborhoods may see increased air pollution if New Yorkers used the expressways to avoid tolls, but the report found no increase in air pollution attributable to congestion pricing.

The analysis used data from one year before congestion pricing and one year after, and tracked concentrations of fine particulate matter, nitrogen dioxide, nitric oxide and black carbon. The report’s findings mark the continuation of a 20-year trend of improving air quality in New York City.

Read the full story, below.

Read the full story: NYC Health Department releases Congestion Relief Zone air quality study results

Wednesday, August 19, 2026 in Mass Transit

Environment Transportation New York New York City Brooklyn-Queens Expressway Trans-Manhattan Expressway Congestion Relief Zone Air Quality Air Pollution New York City Health Department View More

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