Youths sentenced to Virginia's juvenile correctional centers are staying longer, sleeping in rooms that often have no air conditioning and facing severe crowding, an advocacy group reported today.

The problem is not a spike in youth crime. Admissions to juvenile correctional centers are down. But youths are staying longer and behaving worse, driving up expenses for a system that costs $54,000 per youth each year.

Critics fear the trend is making the juvenile correctional centers--once called state learning centers--increasingly like adult prisons, focused more on punishment than rehabilitation. One Richmond area facility, which takes juveniles from throughout the state, is nearly 40 percent over capacity, with more than 100 youths sleeping on plastic beds raised just inches off the floor.

Priscilla R. Budeiri, author of the report by the Virginia Poverty Law Center, based in Richmond, said conditions are becoming "unsafe and unhealthy"--especially for the 78 percent of juveniles with mental disorders.

"Overcrowding often leads to warehousing kids, locking them in their rooms for inordinate periods of time," Budeiri said. "And when those rooms have no air conditioning and minimal ventilation, conditions quickly go from bad to worse."

Officials for the Department of Juvenile Justice, which has 1,360 youths in eight state juvenile correctional centers, acknowledge the crowding and some other problems, which they attribute to the partial closing of one aging facility and other factors.

For example, one in five youths in the centers undergoes sex offender treatment, which takes an average of 18 months, thus extending the time juveniles stay there, officials said. A growing number of offenses committed at the centers themselves also has led to lengthened stays, they added.

Department officials, not judges, decide how long most youths remain in the correctional centers.

"The population we have, they're staying longer," said Christine L. Turner, chief deputy director of the Department of Juvenile Justice.

Turner disputed some of the report's conclusions. "I don't believe that we are to the point at all where we are unsafe or unhealthy," she said.

The worst crowding is at the Bon Air Juvenile Correctional Center in suburban Richmond. It has 385 youths, 105 over capacity. More than one-third of its rooms do not have air conditioning, though the common day rooms do. The individual rooms, which are locked at night, also do not have water fountains.

Because of the crowding, state officials have begun reviewing individual cases in hopes of releasing more youths to ease the situation, Turner added.

There is a long-term trend at work as well, state and local officials say. Former governor George Allen (R), who took office in 1994, and Gov. James S. Gilmore III (R) both emphasized law-and-order themes in their campaigns and promised to be tougher on criminals than their Democratic predecessors had been. Stays at juvenile correctional centers have lengthened as a result.

Officials in Northern Virginia who work with juveniles applauded that shift, saying sentences had been too short. Patricia Romano, director of Arlington Juvenile Court Services, said many youths had been returning home in less than six months.

"Why bother?" she asked. "You just can't address the problems these kids have in less than six months."

But other local officials say that the pendulum has swung too far toward doing time and that rehabilitation and treatment have suffered.

David Marsden, superintendent of the Fairfax County Juvenile Detention Center, which is not part of the Virginia system, said state officials have demonized youths and offered too few programs to assist them. That is making state juvenile officials reluctant to approve releases, worsening the crowding, he said.

"Because you're not providing any meaningful means for change, they can't let go," Marsden said. "They've got a wolf by the ears."