SEATTLE -- Our Puget Sound is unlike any other body of water in the world.

It supports the economy, wildlife and provides recreation for hundreds of thousands of you every year.

But despite how blue the water looks, most experts agree the Puget Sound is in peril.

KIRO 7's Chris Egert begins a series of reports he's spent a half-year on -- with a by-the-numbers look at just how important Puget Sound is.

To really appreciate just how much of an impact this big beautiful body of water has on Western Washington, you need to see it by the numbers.

Puget Sound is just so huge that it is hard for most folks to fathom the environmental issues that our region faces.

"It doesn't look polluted to me," says Emily, of West Seattle. "You have no reason to even wonder about it really."

Puget Sound has 2,500 miles of shoreline. It is an average of 450 feet deep; the deepest part is 930 feet.

There are 10,000 streams and rivers that flow into the Sound, with 3.5 million people living in the region. By 2025, it is estimated that 5.2 million people will live here.

Ships drive the economic engine of Puget Sound: The Ports of Seattle and Tacoma combined are the second-largest U.S. port for container traffic, with an estimated value of $70.5 billion.

Our salmon are just eight of 200 different species of fish. Commercial fishing generates $3.2 billion of annual revenue.

And there are 22 boats dedicated solely to watching our region's three resident Orca pods.

On one of those boats, the Friday Harbor-based Western Prince, crewmember John Boyd has dedicated most of his adulthood to Orcas.

"They are very important to those of us who live out here. For me, it is my career, so I would hate to see them leave," said Boyd, of Western Prince Tours.

Now consider that according to the Puget Sound Partnership, there are 91,700 acres of contaminated mud and sand.

One billion gallons of treated wastewater is dumped into the Sound every day, along with 1 million pounds of chemicals that are legally released into the water every year.

And as impressive as those numbers are, it is about much more than numbers. Puget Sound is about people.

The millions of people who live here, who knowingly/unknowingly contribute to its decline -- and the people working hard to bring these waters back.

Like Jeff June, an environmental contractor who pulls abandoned fishing gear from the bottom of the sea floor.

Dr. Jan Newton, a University of Washington researcher studying fish kills on Hood Canal.

Or Ginny Arveson, of Edmonds -- just a regular person, doing her part to cut down on storm water runoff, one native plant at a time.

You'll get to know them, and appreciate their work, over the next few days.

The rest of the week, Chris will continue his reports on 'Puget Sound in Peril' -- taking you places that few people have ever seen.

Including what lies beneath the water at one of Seattle's most picturesque restaurants.