A private partnership is looking to establish a beachhead on the Hudson River in Manhattan to land a fleet of “ducks,” amphibious buses that would give passengers both a land and sea view of the city. Some civic groups worry, however, that an amphibious invasion will bring traffic and environmental problems.

NY Waterway, which operates commuter ferries on the Hudson, and Gray Line, the city’s largest tour company, have submitted an application to the Army Corps of Engineers to construct a $2 million landing facility for commercial amphibious vehicles at Pier 78, just below the Lincoln Tunnel on West 38th Street.

Gray Line’s vice president of sales and marketing, Michael Alvich, said Tuesday that if the appropriate approvals are obtained, the company hopes to start duck tours next April.

“It will be a lot of fun,” Mr. Alvich said. “It will be a first for New York City.”

The executive vice president of NY Waterway, Donald Liloia, told The New York Sun that the company has yet to decide how many ducks would be operating and what routes they would take in Manhattan.

An unaffiliated, smaller operation has applied for a permit to operate a small fleet of ducks in Brooklyn.

Ducks tours have become popular forms of sightseeing in several waterfront cities, most notably Boston, where in 2004 Boston Duck Tours carried about 500,000 passengers on its fleet of 23 vehicles.

Often on duck tours, guides ask passengers to blow whistles that imitate quacking. The practice has spawned “quack-free” zones in quiet neighborhoods of historic Boston.

The vehicles in Boston carry about 45 passengers. They are refurbished amphibious craft from World War II, nicknamed DUKWs, that were used in several landings in the European and Pacific theaters.

Not all New Yorkers are welcoming the invasion.

“This is Manhattan, not Normandy,” the executive director of Transportation Alternatives, Paul White, said. The nonprofit group aims to reduce automobile use and attendant environmental and social problems.

Mr. White said the area around Pier 78 and Times Square is already a “gridlock alert day, every day.”

“There are much more efficient ways to move tourists around the city,” he said.

Addressing traffic concerns, Mr. Liloia said: “With the number of units running, when you look at total traffic in New York, it is infinitesimal.”

The proposal to construct the landing facility led the founder of the Clean Air Campaign, Marcy Benstock, to express concerns. It was she who mounted a successful challenge to the Westway highway project a quarter-century ago.

Ms. Benstock said she opposes the project because of the destruction of critical nursery habitat for striped bass and “dozens” of other species. She said approval of another waterfront project is part of a larger trend.

“The Corps has been authorizing piecemeal destruction of that habitat,” Ms. Benstock said. “Using tourism as an excuse is bad policy.”

An environmental study that NY Waterway submitted to the Department of City Planning said that because the footprint of the proposed dock is smaller than the current structure, the duck landing pad could be an improvement to fish habitat.

The current application is part of a race to become the first duck-tour operation in New York. There are hundreds of duck boats across the country, running out of about 60 locations.

But New York may be ill-suited for ducks, according to the general manager of Boston Duck Tours, Cindy Brown.

“It’s a tough city for it. I just don’t see how New York can do a successful tour,” Ms. Brown said, citing a difficult permit process and issues of traffic on the streets and safety on the water.

Big Apple Ducks, a startup tour company, aims to run one amphibious vehicle out of Red Hook, Brooklyn, and is currently slogging through the lengthy permit process, according to its president, Carrie McIndoe.

Ms. McIndoe, who wrote the business plan for Boston Duck Tours before studying the New York market, said the Big Apple, with formidable traffic and water safety concerns, is probably the most difficult city in America in which to launch duck tours.

She said the no. 1 challenge was finding a vehicle that would stand up to the wear and tear of saltwater. The refurbished World War II vehicles, built in 1944 and 1945, tend toward rust and frequent breakdowns. Big Apple Ducks bought a new vehicle from Florida and plans to run three vehicles within its first year of operations.

Ducks have been responsible for at least two fatal accidents. In 1999, a duck sank in Hot Springs, Ark., killing 13 of 21 people aboard. The accident, blamed on inadequate maintenance, caused federal safety officials to recommend stricter regulations, including a requirement for backup flotation devices. In 2002, a Ford pickup truck converted into an amphibious vehicle named the Lady Duck sank within sight of the Canadian Parliament in Ottawa, killing four.

In connection with NY Waterway’s application, a public notice from the Army Corps of Engineers said additional review from the state’s Division of Coastal Resources and Waterfront Revitalization is required for approval.

A regulatory branch chief for the Army Corps, Michael Vissichelli, said that if the Corps received enough complaints of a substantive nature before next Thursday, a public hearing would be scheduled.

Less than a year ago, when NY Waterway ran into financial trouble, a lawyer and lobbyist, William Wachtel, purchased from the ferry operator 16 boats and several routes, amounting to less than 50% of the company. Mr. Wachtel is one of the chief fund-raisers for the front-runner for the Democratic mayoral nomination, Fernando Ferrer.

Mr. Wachtel is not involved in the duck project, according to Mr. Liloia.