A fresh round of wrangling has broken out between Sheriff Marlin Gusman and Mayor Mitch Landrieu over the design of the city’s nearly completed new jail, setting up another courtroom clash less than two months after the impasse appeared to have been resolved.

The latest standoff began last week after city officials inspected the 1,438-bed facility and asked the sheriff to produce a final housing plan to prove the lockup — as required by city ordinance — can accommodate groups of inmates who must be separated from the general population.

The city has not yet issued a certificate of occupancy for the $145 million jail, infuriating Sheriff’s Office brass who said they believed the Landrieu administration had accepted the jail’s design in July when the two sides resolved a heated dispute over a city-issued stop-work order that ended up in Orleans Parish Civil District Court.

While city officials said they are merely enforcing the law, Gusman’s attorneys accused City Hall of trying to sabotage the sheriff’s efforts to implement court-ordered reforms at Orleans Parish Prison.

After many months of delays, the Sheriff’s Office has ramped up efforts to open the jail by Sept. 15 — a date Gusman’s attorneys referred to as a deadline imposed by U.S. District Judge Lance Africk.

A court-appointed expert, citing “deplorable” conditions that persist at OPP, recently recommended the city’s inmates be transferred to jails in other parishes if the new facility has not opened by that date.

“The implications for the city’s failure to issue (an occupancy) permit in this circumstance will be catastrophic and result in a massive waste of taxpayers’ money,” James Williams, one of Gusman’s lawyers, wrote in a court motion, asking a judge to intervene and hold city officials in contempt of court.

In a letter to Gusman’s lawyers last week, City Attorney Sharonda Williams described the request for the housing plan as “perfectly reasonable and appropriate,” adding that an outline the city received earlier this summer was “cursory” and subject to change in the final stages of construction. The sheriff’s refusal to provide the information, she wrote, “evinces a disregard for the city, its laws and its officials.”

“It is standard practice for (the Department of) Safety and Permits to request plans to demonstrate compliance with a conditional-use ordinance,” said Brad Howard, a Landrieu spokesman. “Every other business, resident and government agency in New Orleans complies with these requests because no one is above the law.”

James Williams said the Sheriff’s Office had been taken aback by the city’s request because a city inspector had indicated “he was satisfied with everything he observed related to the new inmate housing facility and did not see a reason why a certificate of occupancy permit should not be issued.”

While Gusman insists the new jail can handle all types of inmates — including groups such as women, juvenile offenders and inmates with substance-abuse issues who typically are housed apart from the general population — he wants to build another multimillion-dollar building that would be dedicated to housing inmates in need of such specialized treatment.

The sheriff has said the new building, often referred to as a “Phase III” facility, is needed to satisfy the sweeping requirements of a federal consent decree and to handle the number of inmates. The jail was housing just under 1,800 inmates Monday, several hundred more than the new building is designed to hold.

Landrieu, whose administration is required by state law to pay for the care of local inmates, has opposed the proposal for another building, pushing instead to reduce the city’s notoriously high incarceration rate and its associated costs.

The rift between Gusman and Landrieu involves more than a dispute over buildings. On Monday, the Sheriff’s Office released a letter Gusman sent to the mayor declaring his intention to provide “desperately needed” pay raises for deputies despite opposition from the city.

The sheriff has said one of the greatest obstacles to reforming the jail is recruiting and retaining competent deputies. He wrote that his deputies, who receive a starting salary of $27,000 a year, are “the lowest-paid law enforcement officers in the region.” New Orleans Police Department recruits, by contrast, will receive about $42,600 a year starting in January after two recent pay raises.

A Sheriff’s Office spokesman said Gusman’s pay plan calls for paying new deputies $32,700 a year, rising to $34,000 after six months.

According to a study recently commissioned by the city, a disparity between police and jail deputies is not uncommon, as correctional officers nationally earn about 68 percent of the median salary paid to police officers in the same areas.

But Gusman pointed to several agencies in neighboring parishes that offer far better pay to recruits, and he took umbrage at “certain members of the City Council” who he said had questioned the need for deputies to receive a raise, even as the city has approved 10 percent pay raises for police officers.

“OPSO deputies risk their lives and safety to protect the public from violent criminals, all while ensuring that inmates are housed in a safe, humane and constitutional manner,” the sheriff wrote. “The city’s lack of respect for their job is unjustified and offensive.”

Gusman is a former city councilman and chief administrative officer who had responsibility for the city’s budget for several years during which deputies’ salaries were much lower than they are now.

Follow Jim Mustian on Twitter, @JimMustian.