New York City intends to close its first jail on Rikers Island by summer 2018.

The Department of Correction said Tuesday that the George Motchan Detention Center will be shut down.

The jail holds about 580 detainees — both low-level and serious felony offenders. The city has not confirmed where exactly the detainees will go.

The jail's closure will bring the number of Rikers Island facilities from nine to eight and will not result in layoffs for DOC uniformed staff, as correction officers will be reassigned elsewhere.

The city said it is able to shut the center down because the overall city jail population has dramatically dropped; last week, the city announced the population is under 9,000 for the first time in 35 years.

The closure is part of Mayor Bill de Blasio's plan to close Rikers Island entirely.

In a statement, the mayor said, "This announcement is an important step in our plan to close Rikers Island and create more community-based facilities to better serve people in custody and our hard-working correctional staff."

"The untold story here in New York is that we have the lowest incarceration rate of any large city in the nation, and that's an accelerating downward trend," said Elizabeth Glazer, the director of the Mayor's Office of Criminal Justice.

Correction officials say they do not yet know exactly when the facility will close or what will happen to the buildings, noting that some of them have structural issues, including with the sewage system.