Sheriff’s Office and city officials offered competing plans Friday for housing so-called special inmate populations at Orleans Parish Prison, a sore subject between the two sides that has increasingly drawn scrutiny from the federal judge overseeing a court-ordered plan for jail reform. Sheriff Marlin Gusman called for the “immediate” construction of a new multimillion-dollar jail building designed to accommodate all inmates requiring specialized mental health or medical treatment.

The facility, long referred to as “Phase III,” would fill the space between Gusman’s new kitchen/warehouse building and a 1,438-bed lockup scheduled to open later this year. He estimated its price tag at between $56 million and $97 million, depending on the number of floors.

Under Gusman’s proposal, the building would have between three and five floors, with a capacity of between 380 and 764 beds.

The sheriff called for a “base bid” structure with three floors and 380 beds, totaling 160,436 square feet. Three alternate bids “could only be triggered if the population of the jail is not below pre-determined targets by given dates during the course of construction,” Gusman attorney Blake Arcuri wrote in court filings.

“Using this method, all parties to the criminal justice community would have incentive to take meaningful steps to actively reduce the jail population, as opposed to the multi-year theoretical discourse which has hindered all progress to this point,” Arcuri said. “Simply put, if the jail population is substantively reduced in a timely fashion, the alternate bids are never triggered and the current hypotheticals regarding population are moot.”

Any new beds would be in addition to the 1,438 that the City Council authorized in 2011, with the expectation that the building now under construction would include all inmates except for those with acute mental health issues. However, it turned out the building was not designed to accommodate many classes of inmates with medical or other special needs.

Gusman’s proposal does not include a timetable for completion, but construction would likely take up to three years, based on the sheriff’s interim plans to relocate severely mentally ill inmates to a state prison in St. Gabriel.

Perhaps the least detailed segment of the 188-page proposal for the new building has to do with financing. A single paragraph states the project’s funding would come from Federal Emergency Management Agency dollars recovered from the loss of two OPP buildings damaged in Hurricane Katrina.

It does not elaborate on the amount of FEMA money still available nine years after the storm.

Gusman’s long-harbored desire to build a “Phase III,” rounding out a complex that Sheriff’s Office officials have dubbed the Orleans Parish Correctional Center, clashes sharply with a counterproposal by Mayor Mitch Landrieu’s administration to retrofit the new 1,438-bed jail with a mental health clinic. City officials doubled down on that proposal Friday, estimating in court filings that the work would cost $6.1 million and take 315 days to complete.

The dueling proposals come as Gusman has struggled to fulfill the sweeping requirements of a federal consent decree intended to overhaul OPP and significantly improve jail conditions that U.S. District Judge Lance Africk deemed unconstitutional last year.

Africk and an outside expert he appointed to monitor the jail reform effort have told the sheriff he must find a new home for the city’s most mentally disturbed inmates if he intends to comply with the terms of the consent decree. Those detainees are being housed in a decrepit jail building known as Templeman V.

State law requires the city to pay the cost of inmate care, and attorneys for the city have increasingly fought over how to most efficiently reform the jail. City officials, for instance, are squarely opposed to Gusman’s plan to temporarily relocate severely mentally ill inmates to a facility in St. Gabriel that would require a series of renovations to pass consent-decree muster.

With another costly consent decree involving the New Orleans Police Department to pay for, not to mention the $17.5 million the city owes its firefighters in overdue pension obligations, Landrieu’s administration has shown no appetite to foot the bill for another state-of-the-art jail building. But City Attorney Sharonda Williams acknowledged in court filings Friday that Gusman has rejected the city’s proposal to retrofit the fourth floor of the 1,438-bed jail.

Gusman’s design and construction team says such a renovation would be impossible at this point in the construction. Arcuri, the sheriff’s attorney, said that modification — which he contends was suggested by the sheriff a year ago but “vehemently opposed” by the city — would require the jail to first “be completed as planned, after which a new plan for retrofitting would need to be rebid.”

“This would cause a drastic delay in moving inmates out of the current dilapidated facilities, which the city refuses to maintain or repair, and into a state-of-the-art facility with modern living conditions,” Arcuri wrote. “Further, the plan would drastically reduce the population of the 1,438-bed facility, leaving a substantial number of inmates being housed in temporary or outdated facilities for an extended period of time, if not for years.”

City officials have countered that the sheriff could quickly reduce the population of approximately 2,000 inmates by a few hundred by returning state inmates to the custody of the Department of Corrections.

Williams also wrote in her filing Friday that city officials would not be opposed to the indefinite use of an overflow jail building such as the Temporary Detention Center “for a period of time while the (jail) population continues to decrease.”

The debate over the proposed “Phase III” facility is likely to revive a broader discussion about the size of New Orleans’ jail, which reform advocates believed would be capped at 1,438 beds when the City Council approved the construction of a $145 million jail in 2011. The ordinance for the new jail said it should accommodate “any type of prisoner under any jurisdiction,” excepting only “inmates that require acute mental health treatment.”

Gusman’s “Phase III” proposal, however, would provide housing for more than just acutely mentally ill inmates. The plan includes 28 beds for male inmates who require “sub-acute” mental health treatment and another 64 for recovering male inmates who require “step-down” treatment after experiencing mental health issues. Another 18 beds would be dedicated to female inmates classified in need of either “acute, sub-acute or step-down” care.

The other beds included in the “base bid” would be used for minimal security inmates and those requiring special medical needs.

City officials expected the new 1,438-bed jail to accommodate “inmates with medical and mental health conditions,” Williams wrote. Arcuri countered that city officials should have known 31/2 years ago that the new jail was not intended to house acutely mentally ill inmates, though he did not address the expectations for the so-called sub-acute and step-down populations.

Follow Jim Mustian on Twitter, @JimMustian.