A SOUND WAY to judge the health of a city's public housing system is to look at the time it takes that city to renovate and re-rent vacated apartments. Effective public housing systems stay on top of the job and do not fall behind. Good management pays through lower maintenance costs. It pays because the apartment is not left to deteriorate for months. It pays when poor families get into public housing without waiting several years.

The District's housing and community development director said recently that workers will be readying vacated public assistance apartments for new tenants "within three months." Sadly, this was said to indicate vast improvement. It is unacceptably lethargic. New York has nearly 17 times as much public housing as the District, but it regularly has vacated public housing units ready in five to 10 days. Only 480 units of Baltimore's 18,106 public housing apartments are vacant. More than 2,000 of the District's 11,749 units are vacant, an appalling number when the city's waiting list for public housing has 11,000 names on it. Those are some of the reasons why a high-ranking U.S. Housing and Urban Development Department official was assigned to help the District get its public housing into shape.

The District is paying for years of bad management. Rehabilitation of vacant apartments has become much more costly and time consuming because of deterioration and vandalism. The city cannot keep up and complains of staff shortages. Other cities use private contractors only for massive renovation jobs or after fires; the District finds itself handing out work to private contractors simply because it has fallen behind. The city also complains about a lack of money. But HUD's audit showed that the city was losing $1.4 million annually through lost rent from vacant units. HUD officials also cut off millions of dollars in funds that would have been available through the federal Comprehensive Improvement Assistance Program. Why? Because the District was too slow in using the money.

The time for excuses, explanations and promises from the city has passed. The families on the waiting list deserve something better. If the city has to pay more for private contractors to renovate them now, then so be it. "Getting ahead of the curve," as Mayor Marion Barry is fond of saying, would not have been such a monumental and costly task if the city's public housing had been adequately managed in the past.