“Though there are some disagreeable things in Venice,” Henry James once wrote, “there is nothing so disagreeable as the visitors.” The Grand Tour was still de rigueur when those words were written, and if James was put off by the parasol set, you can only imagine what his reaction would be to the Venice of today. “Disagreeable” would surely not be his epithet of choice.

Some 14 million tourists descended on Venice last year to mingle among – or, more rightly, stampede over – the dwindling local population. In 1950 there were 175,000 Venetians; today there are 64,000. Who can blame them for leaving? Anyone who works in Times Square or lives in SoHo knows what it’s like to feel a stranger in your own home, surrounded by hordes of gawkers, junkshoppers, and oblivious pedestrians. Lucky for us, Manhattan is a giant metropolis; unlucky for the Venetians, mass tourism threatens to become the sole raison d’etre of their fallen island paradise.

This is the Venetian dilemma. The magnificent city is dying, but the profitable theme park thrives: Its economic lifeblood is also a poison. The effect of tourism on Venice and the lives of its residents is the subject of Carole and Richard Rifkind’s slight digital-video documentary “The Venetian Dilemma.” New Yorkers who have lived part-time for many decades in Venice, the Rifkinds have seen first hand the troubling acceleration of tourism on their adopted city, and their report benefits from easy familiarity with the place and its people.

The movie takes as its subjects two representative citizens. Michela Scibilia is a graphic designer, mother of two, and author of a guidebook promoting “intelligent tourism” in Venice. Resigned to the inevitable crowds of sightseers, she believes that by promoting traditional, owner-operated bars and restaurants, authentic local culture may be kept from extinction. In her personal life, she is concerned by the city’s lack of childcare and organizes families to agitate for better civil services. Venetian children are “like pandas,” she says. “They need to be protected.”

Danilo Palmeri sells fresh vegetables from a graffiti-covered kiosk located in a piazza overrun with bars and sprawls of outdoor restaurant seating. The city considers him an eyesore; Mr. Palmeri thinks himself the last vestige of traditional Venetian life. He worries about the government indifference to working-class Venetians. While the nobility busies itself renovating their abandoned palazzos with city help, his family struggles to keep up their deteriorating16th-century apartment.

Another protagonist, or perhaps antagonist, is Robert D’Agostino, Assessore of strategic planning. Mr. D’Agostino has a vision of Venice as a modern, efficient, business-friendly utopia. His efforts are centered on the Arsenale, a small, formerly industrial island adjacent to Venice.

A convention center and cruise-ship port are in the making, but his greatest ambition is to construct an underwater metro from the mainland airport. It is estimated that 5,000 jobs would be created by the project, and that 20,000-60,000 people would use it each day. A boon to overcrowded Venice? You do the math.

Along with these interviews and abundant Venetian street scenes, the Rifkinds record elderly Venetians warbling nostalgic, patriotic ditties, as well as provide the occasional animated map. What they don’t provide is much depth or breadth to their subject. The Venetian dilemma is fascinating; “The Venetian Dilemma” is maddeningly superficial.

The city’s university is more than once mentioned as the only source of vitality other than tourism, yet we learn almost nothing about it or its students, who presumably have a lot to say about their role in city life. I’d have liked to know some – or any – facts and figures about the 64,000 Venetians; been given a richer understanding of the environmental and infrastructural problems; learnt about the cultural life of the city; even heard from the tourists themselves.

Strange, too, how deadly dull Venice looks through the Rifkinds’ camera. They need not worry, at least, that their documentary will boost tourism.

At Film Forum until March 22 (209 W. Houston Street, between Sixth Avenue & Varick, 212-727-8110).