THURSTON COUTY, WA - Lower-risk inmates would be housed in sprawling, 64-bed dormitories instead of single cells in the new Thurston County jail, under a design plan released Monday.

"It's inexpensive construction," said Thurston Chief Deputy Sheriff Karen Daniels, who runs the jail. "You have one secure perimeter wall, instead of building a lot of interior walls along walkways and cells."

The proposal, which also includes some single cells for maximum-security inmates, is based on a prison management system called direct supervision. With it, correctional officers work in the same area where inmates live in the dormitories, rather than monitoring a ring of prisoners in single cells from a central enclosed officer station.

"If there's a barrier, you're just sitting there, waiting for them to act out," Daniels said. "If you're with them, if someone gets a 'Dear John' letter, you can intervene before something happens."

Daniels made her comments Monday at a briefing for Thurston County commissioners on the proposed new jail, or Accountability and Restitution Center. The facility, planned for a 27-acre site at the Mottman Industrial Park in Tumwater, is expected to cost $31.5 million for the first phase.

County officials wrestled for almost two hours with what Daniels called "how to get the most bang for the buck," while not sacrificing accepted practices for jail management. The proposed arrangement, set for a hypothetical prison population in 2010, is geared toward an ideal plan that avoids double-bunking maximum security inmates and shuts down a 92-bed trailer that has served as a county jail annex for 10 years.

Under the ideal plan, the new jail would add 192 beds to the current capacity of 313, not including the trailer. The 505 beds would be a net gain of 100 beds compared with the current 405-bed capacity.

Daniels said she favors the ideal plan because it doesn't include double-bunking - adding an extra bed to maximum-security cells - a practice the county uses but wants to avoid since violent criminals can be dangerous not only to officers but to each other, Daniels said.