This sketch shows what the county prison will look like when it is finished in September 2007. The prison, which is estimated to cost between $34 million and $40 million, will house 512 prisoners. The building will have three floors, including mezzanine levels on the second and third floors. A basement will provide areas for booking and holding prisoners, as well as the kitchen.

Going hand in hand with a growing population in Butler County is a rising number of prison inmates.

Rich Gigliotti, warden of the county prison, said the county still is the fastest growing in Western Pennsylvania.

"And there's a direct correlation between the civilian population and the inmate population," he said.

To handle overcrowded conditions at the prison on West Vogeley Street, the county commissioners in 2004 approved building a new prison on South Washington Street at the site of the former prison annex.

Construction of the $34 to $40 million building is under way and expected to be completed on Sept. 27, 2007.

Gigliotti said work is on schedule.

AG Cullen, the project's general contractor, has been onsite for a few weeks.

The concrete work, which includes building seven walls, is expected to be done by the end of the month.

Crews started installing sanitary lines at the beginning of the month.

About 1,100 tons of steel will be used in the 167,577-square-foot building.

Although the new prison technically has only three floors, there also are mezzanine levels on the second and third floors, as well as a basement.

Under the current design, inmates would be driven into the basement level from West Vogeley Street. The exit for this secure entrance would be on West Cunningham Street.

The basement includes areas for booking and holding prisoners. The kitchen and laundry facilities also are on this floor.The new prison's entrance will be at the first floor on South Washington Street. Work-release prisoners will be housed on this floor, where medical and physical training facilities also will be located.Along with a fully functional hearing room, there also will be two large classrooms on the first floor.The second and third floors, along with their balcony-like mezzanine levels, each will house several modules.Prisoners will be separated by categories of crimes. For example, an inmate who murdered a pedophile will be kept in a different module than pedophiles.Male and female prisoners will be separated.Each module, which will house 61 to 64 inmates, will include exercise and multi-purpose rooms.While awaiting construction of the new building, prison officials are housing Butler inmates in various locations.Temporary cells inside the basement of the city tier garage replace the former prison annex, which was demolished last year to make room for the new prison.In February, there were 118 inmates in the main prison and 40 in the tier garage. The new prison is designed to hold 512 beds.Since the county tries to keep the number of in-house prisoners below 160, more than 70 are typically kept in other county prisons, including Lawrence, Armstrong and Clinton.Butler County spent $1.2 million in 2005 to house inmates in other county prisons.County officials hope to save some transportation costs of the county sheriff's department through videoconferencing at prisons in other counties.Another step addressing the overcrowding is the expansion of the county's house arrest program to include all of the people arrested who do not need to be incarcerated.Gigliotti said the number of people wearing electronic monitors has increased under President Judge Thomas Doerr of Butler Common Pleas Court."Not everybody has to come to jail," Gigliotti said.

The concrete work for the new county prison on South Washington Street, which includes building seven walls, is expected to be finished by the end of the month. About 1,100 tons of steel will be used in the construction of the 167,577-square-foot building, which will house up to 512 inmates.