Neighborhood gentrification is a mixed bag for cities.

On the positive side, as the word implies, gentrification brings into neighborhoods people who are financially better off than those already living there. What city wouldn’t want residents who have more money to spend at local stores and restaurants?

But the flip side is that the size of urban neighborhoods is fixed; there’s no room to grow (though there’s an escape hatch I’ll get to). If new people come in, other longtime residents get pushed out.

New Orleans Mayor Mitch Landrieu last week said that considering all of the problems city administrators can face, gentrification “is a good problem to have.” It means you’ve made your city more attractive as a place to live.

Last week I wrote about how census figures show that many large cities are growing again, even faster than the suburbs that surround them. That’s a dramatic reversal from the decline of American cities throughout the second half of the 20th century as urban dwellers headed for the suburbs.

“Back in the day, people thought isolation and distance were going to give them happiness,” Landrieu said at a panel of American mayors at the Essence Festival on Saturday. “What’s happening now is people want to be with other folks.”

But with the new growth of cities comes the problem of gentrification. We’ve seen this happen in New Orleans in a number of neighborhoods. And we’ve seen the resulting clash of cultures, such as in the battles over live music at neighborhood venues.

The issue was raised once again this week with the news that businessman Sidney Torres IV has filed suit against Buffa’s, a neighborhood bar on Esplanade Avenue. Torres, who owns a three-story mansion next to the bar, complains in his suit about “the noises emanating from the property.”

The battle also can be waged over structures. The most high-profile battle on that front recently was over the former site of the Holy Cross School in the Lower 9th Ward. The City Council ultimately decided to approve a proposal for two 60-foot residential buildings there. Opponents wanted the towers to stay within the current 40-foot height requirements and bemoaned what effect the development might have on the neighborhood’s character.

I noted earlier that old urban neighborhoods are fixed in size, with no room to expand. Well, as the Holy Cross experience shows, there is one way to expand, and that’s upward. By building residential towers, you can squeeze more of the “gentry” into a desired neighborhood.

A similar controversy embroiled Gretna a decade ago. The city’s downtown — essentially, what Gretna consisted of 100 years ago — is full of old buildings, and the whole area is on the National Register of Historic Places.

Developers proposed a condominium tower on the Mississippi River in old Gretna, another way to bring more people into a neighborhood by building up where you couldn’t build out. Residents objected, but the potential detrimental effect on the neighborhood’s character didn’t seem to matter and the city approved the plans anyway. Eventually, however, Hurricane Katrina struck, and the condos were never built.

Some people scoff at the anti-gentrification argument. They say that it’s hidebound traditionalism like that which puts Louisiana at the tail end of most quality-of-life surveys and explains why New Orleans continues to be outstripped by cities like Houston or Atlanta.

That argument ignores the fact that anti-gentrification sentiment exists in other cities as well, even such successful urban giants as New York and San Francisco.

And besides, not being another Houston or Atlanta is what attracts people to New Orleans, isn’t it?

Dennis Persica’s email address is