NEW YORK (AP) _ Leonard Thomas, a drawbridge operator on Brooklyn's Gowanus Canal, looked down from the Union Street bridge one day recently and saw a blue crab skittering under the water. Then another, and another.

Thomas, 49, who has a second life as ``Chicken Man,'' the author of a popular cookbook of chicken recipes, was delighted _ and inspired. He climbed back into his tower and sat down to invent a new dish. ``I'm calling it Gowanus Gumbo,'' he says. ``Chicken stuffed with crabs.'' Pause. ``But not THESE crabs ...''

While still far from edible, marine creatures are returning to the Gowanus, the notoriously polluted ditch that winds just over a mile through a wasteland of old factories, junkyards and derelict buildings.

Until recently, the Gowanus was known as New York state's most toxic waterway and _ though it never caught fire like Cleveland's Cuyahoga River _ was among the foulest in the nation, too.

But that changed in May when the city, responding to demands by community groups, completed a $10 million repair of the canal's 90-year-old ``flushing tunnel,'' which had sat idle since it broke down in the 1960s.

Once again, the tunnel's 12-foot-diameter bronze ship's propeller is pulling 300 million gallons of water a day from New York harbor, driving it through the canal and back into the harbor at the other end.

``We're bringing in fresh water at a rate that entirely changes the canal's water every 23 hours,'' said Joel Miele, the city's environmental protection commissioner. ``Since the harbor itself is the cleanest in 70 years, any flora and fauna capable of surviving in the harbor can do the same thing in the Gowanus, and they are merrily doing that as we speak.''

In just weeks, water that was once the color of skim milk mixed with motor oil has become dramatically clearer. It is now possible to see crabs and fish beneath the surface _ along with the trash on the bottom.

A slow-moving, purplish oil slick proves there's a current in the 60-foot-wide canal. Jellyfish float past, Atlantic-bound, with bits of garbage and paper wrappers. Near the Carroll Street bridge, two geese and a duck paddle happily about.

Thomas says a cormorant, a diving bird that feeds on fish, regularly perches on a containment boom to dry his wings.

As for the canal's infamous odor, he said, ``A year ago you couldn't stand it. Now, sometimes, it almost smells like sea water.''

John Muir, director of the Brooklyn Center for Urban Environment, calls the swift return of marine life ``an astounding development.''

``Two months ago this place was a biological desert. ... The water was nearly opaque and devoid of oxygen,'' he said. ``Any living thing that got anywhere near the outlet would run up against a wall of deoxygenated water.''

Now, most of the new sealife is ``migrating upstream from Gowanus Bay,'' Muir said.

The next step is to clean the bottom _ an expensive task that Miele says may require city, state and federal cooperation.

Muir said samplings show a canal bed coated by a ``uniformly awful,'' highly toxic accumulation of ``tarry-looking stuff, equal parts of petroleum precipitate, and to put it politely, organic materials settling out of sewage overflow.''

Muir was too polite to mention non-organic material such as discarded condoms, known in local parlance as ``Brooklyn trout.''

The canal's name comes from Gouwane, chief of Brooklyn's Canarsee tribe. It earned a place in history in 1776 when its swampy waters helped delay British redcoats long enough for Gen. George Washington, defeated in the Battle of Long island, to escape to Manhattan.

A century later, the natural creek was dredged to create a barge route into downtown Brooklyn, eventually attracting stoneyards, tanneries, foundries, paint and ink factories, paper and flour mills, electroplating shops, coal, lumber and gas distributors.

In 1893, Brooklyn's Daily Eagle called the canal ``an open cesspool.'' And the term ``gas house gang'' first applied to bands of thugs who ambushed sailors and other innocents from hangouts along its banks.

The fact that many famous mobsters came from nearby Carroll Gardens encouraged myths of the Gowanus as a convenient place to dump inconvenient bodies. One local man half-jokes that the bottom cleanup will reveal ``leg bones tied to cement blocks.''

But inhabitants say corpses rarely turn up with the bicycles, Christmas trees, shopping carts, highway cones and auto parts that emerge at low tide.

``Somebody said it one day and it sounded good,'' says junkyard owner Dan Tinney. In his 23 years, Tinney said, ``two, maybe three'' bodies have been hauled out. Once, police spent hours recovering what turned out to be a mannequin planted by pranksters.

These days, barges delivering oil to a fuel depot next door are virtually the only customers that gourmet-bridge tender Lenny Thomas has to worry about: ``Maybe once a week during the summer, more often in the cold weather.''

But there already are signs of a new life for the canal. A film documentary, ``Lavender Lake,'' plays in local theaters, periodic boat tours draw capacity crowds, and a Gowanus Canal Web site (www.gowanuscanal.com) recorded 28,000 hits in one week _ almost three times the average _ after newspapers reported the crab discovery.

Web site designer Mark Phillips says the publicity also spurred sales of his ``Gowanus Canal Yacht Club'' T-shirts. ``A lot of people are canal buffs,'' he said.

Officials expect the canal's comeback to revive a shabby South Brooklyn neighborhood whose best-known business is a casket factory. Real estate entrepreneurs have displayed nibbling interest. And there is talk of a canalside park with weeping willows, outdoor cafes and paddleboats for rent.

``Chicken Man'' Thomas likes that idea. ``Walkways along the water would be nice. Water has a calming effect on people,'' he said. ``Maybe even a grill _ chicken on the canal.''

``I think it would be nice to have a bunch of fountains, a promenade,'' agreed Risha Gorig, 29, a German-born sculptor who lives by the canal with her boyfriend and a rescued pit bull. She also imagines their canalside lot, shared with the owner of a garish houseboat, as the center of an artists' colony.

Tinney, the junkyard man, said a promenade ``sounds terrific,'' but wouldn't be practical, as the canal's three bridges _ each of which opens in a different way _ are too low to walk under. He said he favors commercial development such as caterers, restaurants and a ``mini-shopping mall.''

``I think in the end it'll be a mix. it may not happen in our lifetime, but it will happen. This is the last jungle, the last frontier _ there's nowhere to go from here,'' he said.