Ferries help the poor? That’s rich.

Mayor Bill de Blasio has insisted that his administration’s heavily-subsidized ferry service would help poor New Yorkers get around, but newly revealed data shows it’s been a plaything of the rich almost from the jump — figures the city sat on for months.

An internal survey taken in July 2017 — two months after the service’s inception — found that the median rider’s income ranges between $100,000 and $150,000, a trend that held as of another poll conducted in the winter of 2018.

The results of the surveys were obtained by The Post through an eight-month Freedom of Information Law battle with the Economic Development Corporation, the city-controlled non-profit that manages the ferry service and solicited the data.

The EDC for months rebuffed The Post’s requests as it claimed it was still searching for the records — but City Councilman Antonio Reynoso had a different explanation for it.

“The city was being misleading about what information they had, and also didn’t want to give the information because it would prove a point that many of us were already making,” said Reynoso (D-Brooklyn/Queens).

In an April 2019 City Council hearing, the EDC’s Chief of Staff told Reynoso he didn’t know about the income levels of those riding the ferries, which are subsidized with taxpayer funds to the tune of $9.34 per trip, as of October.

“We don’t have information on who precisely is riding the boats today,” James Katz told the joint committees on governmental operations, economic development and transportation at the time.

But the new documents prove that by that point, EDC had conducted three surveys, two of which asked about income data and found that the median ferry rider pulls down a six-figure salary.

A fourth survey — leaked to another outlet in October as The Post’s FOIL request was pending, in what watchdogs have called a possible violation of state open records law — conducted across May and June 2019 found that 65 percent of riders make over $75,000.

That survey also, for the first time, gathered data on race, and found that 64 percent of riders are white, as compared to approximately 50 percent of the ferries’ service area.

Those figures scuttle de Blasio’s breathless assurances that the ferries are the wave of future for transportation in this city, and would serve as a socioeconomic equalizer.

“The city knowing this information and continuing to subsidize at a very high rate just shows where their priorities are when it comes to transportation,” said Reynoso, a member of the City Council’s Committee on Transportation.

“They get into a back and forth with Gov. [Andrew] Cuomo about how much [the city] should put into the MTA, which is used by a more diverse [group] of people,” continued Reynoso. “And we’re subsidizing that at a fraction of the cost that we’re subsidizing the ferry system.”

Transit advocates agreed that if the mayor really wants to help everyday New Yorkers get around, he should start on land.

“The average income of a New York City bus commuter is under $30,000,” said Ben Fried, spokesman of the TransitCenter think tank. “If the mayor is serious about making the city fairer, the least he can do is give his bus lane program the same resources he gives his ferry program.”

Reynoso made clear that he’s in favor of the ferries, assuming that City Hall can make them work for those who need them the most.

“I think the ferries are good,” he said. “For me, it’s about where we want to put these subsidies and who’s benefiting from the tax dollars that we’re spending.

In a statement, the EDC argued that ferry ridership has gradually gotten more diverse, and continued to insist that it simply didn’t have sufficient data at the time as of the April 2019 council meeting.

“As we’ve expanded the ferry system beyond the old East River route, it’s serving a much more diverse group of riders,” said EDC spokeswoman Shavone Williams. “We look forward to expanding this service in the coming months to neighborhoods that have endured unacceptably long commutes to the city’s job centers, including Coney Island, Ferry Point Park and Staten Island.”

“When asked at the hearing about ridership demographics, we did not have comprehensive data on all routes to share,” Williams added of the council meeting.

“To better guide our efforts and answer the legitimate questions of the City Council, we undertook a more comprehensive survey in the summer of 2019. We then … briefed interested council members on that data and data from 2017-18 — and published all this information on the NYCFerry website for the public.”