Stephen Ross said on Friday that he will contribute an initial $100 million for the funding of the planned Detroit Center for Innovation development.

Ross, who is worth $7.6 billion, had previously been mum about his financial stake in the planned development on the former Wayne County Consolidated Jail site downtown along with fellow billionaire businessman Dan Gilbert and the University of Michigan, Ross' alma mater.

The new detail came during Crain's annual Newsmaker of the Year luncheon, during which Ross, chairman and founder of New York City-based development giant Related Cos., was being honored for his role in spearheading the effort to transform the 15-acre site at Gratiot Avenue and I-375.

"Three hundred million (dollars) minimum must be raised from philanthropic sources," Ross said at the event. "Yes, I'm gonna be making a very substantial gift. I do believe in it, and I believe in the impact it can have."

Ross said his "initial gift" of $100 million will go toward the funding of the development, which could top $750 million.

News of the development was formally revealed in October. Crain's first reported on the project in May. It would be anchored by a $300 million University of Michigan graduate school initiative for students in things like mobility, AI, sustainability, cybersecurity, financial technology and other fields.

The first phase of the project includes the 190,000-square-foot UM academic building, startup incubator, housing, hotel and conference center, according to a news release. The project is expected to break ground next year.

Once finished, the academic building is expected to serve up to 1,000 graduate and senior-level undergraduate students. The university expanded its presence in the city with its participation in a new school on Marygrove College's campus in the northwest part of the city.

One of New York City's most powerful real estate developers, Ross had long been reluctant to invest in his hometown of Detroit because he was not convinced the financially troubled city would yield a return. After seeing signs of a turnaround, and plenty of convincing from Mayor Mike Duggan and Gilbert, Ross is buying into the Detroit comeback story rallied by its residents and corporate community.

Ross stuck a toe in the water in 2017 when he put $7.5 million into a $27.5 million housing project with the Ford Foundation and Detroit-based The Platform LLC.

Once complete, the Detroit Center for Innovation and accompanying development is expected to have housing across buildings 10 to 15 stories high, a boutique hotel and conference center in the former Detroit Police Department headquarters at 1300 Beaubien St. and business incubator space on the site of the now-demolished jail project, which is being replaced by a $533 million Gilbert-built consolidated jail and criminal Justice complex at East Warren Avenue and I-75.

"This investment reinforces the county's decision to pursue an alternative to finishing the Gratiot jail," Wayne County Executive Warren Evans said in the release.

Some in the University of Michigan community have opposed the innovation center project because they believe it is "antithetical to the university's stated values of equity, empowerment, and community-centered public engagement," according to a student petition.

Ross has acknowledged the innovation center — modeled after Cornell Tech, an urban campus on Roosevelt Island in New York City — is ambitious, but remains confident. A variety of approvals are still needed for the project, and financing structure and tax incentives or abatements have not yet been determined.

Ross, the nephew of the late Detroit businessman Max Fisher, owns the NFL's Miami Dolphins and is UM's largest donor, having contributed $350 million to the university, whose renowned business college bears his name.

Gilbert, the founder and chairman of Quicken Loans Inc. and Rock Ventures LLC, was also being honored for his work over the last decade in Detroit, which included billions of dollars in real estate investment and bringing approximately 17,000 of his employees to the downtown core. Gilbert, who suffered a stroke in May, is being given the first Crain's Newsmaker Hall of Fame award.

— Crain's Detroit Business reporter Kurt Nagl contributed to this report.