More than 38,000 D.C. residents do not speak English very well, and their numbers are growing, according to a study released yesterday as city officials prepare to implement a new law requiring delivery of vital services in other languages.

Two-thirds of those with limited English skills are Spanish speakers, who also account for the majority of new immigrants to the city. Half the city's Spanish speakers have limited skills in English, the Brookings Institution study said, as do even higher proportions of Chinese and Vietnamese.

With immigration soaring, the number of people with limited English skills rose in the District by nearly a third in the 1990s, said the study, which was based on census data. One in five city residents who told the Census Bureau they do not speak English very well was born in the United States -- likely the children of immigrant parents, according to the study's principal author, Audrey Singer.

Most new immigrants live in the suburbs, so the population that does not speak English very well rose most sharply outside the city -- by 74 percent in Montgomery County and 105 percent in Fairfax County, for example. Regionally, Spanish also dominates among people who do not speak English very well.

At a forum co-sponsored by Brookings and the office of Mayor Anthony A. Williams (D), speakers said the new city law would help integrate immigrants into society and recognize their value to the local economy. Some criticized the recent comment by Maryland Gov. Robert L. Ehrlich Jr. (R) that multiculturalism is "bunk." But they also emphasized that the D.C. law represents a change of culture for city government that will require time. The deadline for implementation is October 2006.

The city is not yet a national leader in providing equal services to immigrant residents, Williams said, but "we believe in this law. We're going to make it work."

The law, signed by the mayor in April, requires nearly two dozen city agencies to implement plans to hire bilingual employees and to translate their most important documents, such as applications and complaint forms. Initially, it will cover Spanish, Mandarin, Korean, Vietnamese and the Ethiopian language of Amharic, with more languages added as the need grows.

"I do believe it's important for people to learn English, as it's important for me to learn Spanish," said D.C. Council member Jim Graham (D-Ward 1), who represents an area where four in 10 public school students do not speak English at home. "We have to deal with people where they are. We can't deal with them as a wish list."

Each agency does not have to translate all its important forms into all five languages, but it must assess which languages are most likely to be spoken by its clientele and act accordingly. Gustavo F. Velasquez, executive director of the city's Office on Latino Affairs, said some city departments have made progress, including the Department of Mental Health and the police.

People who telephone the mayor's call center can get help in their native language, he said, but the goal is to have that happen when they call agencies directly.

"I would expect resistance" from some city employees, he said. But he added, "Latinos and other [limited-English speakers] want to learn English."

The budget for administering the new law is $300,000 for the first year, said Kenneth Saunders, director of the D.C. Office of Human Rights, which is overseeing implementation, but costs are expected to rise in subsequent years.

In Oakland, Calif., which passed a similar law three years ago, city official Deborah Liu warned D.C. officials that foreign-speaking residents are so eager for help in their own language that they won't be able to contain themselves.

"People are thirsty," she said. Once they find someone to talk to, they will "pour out their life histories."

D.C. Latino Affairs Director Gustavo F. Velasquez credited the mental health and police departments with progress in helping non-English speakers.