NEW YORK (CBSNewYork) — If you think there are more whales in our area, you’re not alone.

Scientists say the whale population has already doubled in New York Harbor compared to last year, and scientists say it has a lot to do with better water quality.

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CBS2’s Lisa Rozner went behind the scenes with the Department of Environmental Protection to find out why.

Drone Force 2 flew from Great Kills Harbor on Staten Island into the Raritan Bay, where just last Tuesday a humpback whale was spotted around 50 feet away from a fishing boat.

“We were just going on about our day and then we heard it come up, the breathing with the big blow hole,” Matt Lanier said.

“It was maybe half the size of a bus,” Alex Carr added.

New York Harbor (Photo credit: Garrett Ziegler)

The number of whale sightings have skyrocketed. The non profit Gotham Whale tracked just three sightings in 2011, but there were 80 times more — 241! — in 2018.

One reason for the turnaround is there’s more menhaden — or bunker fish — in the water and a lot less pollution.

Rozner went out from Astoria, Queens to test the water with NYC DEP Commissioner Vincent Sapienza, who said billions of dollars are being spent every year on 14 wastewater treatment plants and cleaning the harbor.

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“So in 1980s, there were hundreds of billion of gallons a day of untreated sewage going into local waterways and it’s significantly less now,” Sapienza said

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Documented by DEP marine scientists, who spend their days on the water, more and more they’re finding low levels of bacteria and high amounts of oxygen which draw marine wildlife. The testing is done with the help of equipment known as a “rosette,” which is launched into the harbor with a crane. On it are an array of sample bottles and they can run tests immediately on the boat.

“And so when the water comes back on board they collect it by just simply filling up a bucket,” Sapienza said.

There are 89 spots throughout New York Harbor that the crew will test. They go out every day in the summer with the machine.

“When I was young, people didn’t want to go to the water, because it was objectionable, and now you see people flocking there,” Sapienza said.

That’s why the co-workers who spotted the humpback are already planning their next fishing trip. And for John Ponzio, who was celebrating his birthday, “It was probably one of the greatest birthday presents you would ever want.”

The gift of clean water for him and all of New York City.

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To see water quality test results, please click here.