The Census Bureau will have to abandon years of work it has conducted on a household survey that is intended to replace the long form in the 2010 census unless Congress acts soon to provide adequate funding for the project, the agency's director said yesterday.

The American Community Survey is designed to offer neighborhood-level numbers every year, in contrast to the once-a-decade portrait from the census.

The Bush administration's budget requested $165 million for the survey this fiscal year. The House appropriations bill that funds the Commerce, Justice and State departments provided $146 million. A bill approved by the Senate Appropriations Committee gave it $65 million.

Agreement on a compromise is not likely at least until after next month's elections, and census officials are concerned that House-Senate negotiators might take the typical route of splitting the difference between their amounts.

"If the Senate mark were to survive, it would be impossible to go forward with the American Community Survey, and we'd have to do something different," Census Bureau Director C. Louis Kincannon said yesterday. "It has to be pretty close to the House figure. . . . This is not a traditional appropriations situation where you can split the difference."

The bureau mails the survey to about 65,000 homes each month, and officials say they need data from 250,000 homes a month for five years to offer a reliable, neighborhood-level substitute for the long form. The full rollout, repeatedly postponed for lack of money, must begin by early next year, Kincannon said. The Census Bureau has spent $334 million on the project since the mid-1990s.

Kincannon said census officials need to know soon the survey's fate because its elimination would require them to plan quickly for a long form in the 2010 census. If that happens, the bureau would stop collecting survey data next year and reassign about 1,000 jobs at its Suitland headquarters and across the country.

The survey would not replace the short form that supplies basic population and racial counts used to reapportion congressional seats and redistrict political boundaries. The long form, which was sent to one in six households in 2000, includes questions about education, income, commuting, immigration and other topics that guide government programs and marketing decisions.

Some critics contend that those questions, which the survey also asks, are an invasion of privacy, but Kincannon said he does not think that played a role in the Senate appropriations figure. "Money is scarce and that makes it difficult for the Congress to agree to new expenditures," he said.

Census officials met with congressional staff last week to warn of the survey's possible demise.

Barbara Everitt Bryant, who headed the Census Bureau during the administration of President George H.W. Bush, said she wrote congressional appropriators this week urging more money for the survey, which she said would be "an enormous improvement" over the census long form.

"I am very worried about it because we think the time has come for the ACS," said Joe Salvo, New York City's chief demographer. City planners, he said, yearn for more current numbers than the census offers once a decade.