Melina Kanakaredes starred as a detective until she quit earlier this month.
"We're giving her a noble exit," said Reiter, who acts as the show's co-executive producer. "We chose not to go the route of killing her off or having her go missing. We felt that would weigh too heavily on the team."
Meanwhile, showrunner Pam Veasey revealed that Stella will relocate to New Orleans: "She left to run a lab there and she picked that city because it's the city of Katrina, the city of BP oil, the city where people are looking for someone to lend a hand.
"She'll essentially be Mac in New Orleans. We wanted to do something that was respectful and made a lot of sense."
CSI: NY will air its seventh season premiere - 'The 34th Floor' - on September 24.