Two lawsuits aimed at preventing the start of a $1 billion mixed-use development in Glen Cove have been dismissed, paving the way for the project’s construction to begin.

A state Supreme Court judge on Thursday dismissed the lawsuits filed by a group of residents and the Village of Sea Cliff against the City of Glen Cove’s approvals of the Garvies Point project.

The redevelopment will eventually bring 555 rental apartments, 555 for-sale condos, about 75,000 square feet of retail and office space and 28 acres of waterfront esplanades and parks to a 56-acre site on Glen Cove Creek formerly occupied by heavy industry and junkyards.

The city has already given site-plan approval for the project’s first phase, which includes six buildings of four, five and six stories on the eastern portion of the property that will contain the rental apartments and about 25,000 square feet of retail.

Glen Cove officials had signed a land development agreement with the project’s original developers in 2003 and initial approvals were granted in 2008. But in the lawsuits that challenged the project’s approvals, Sea Cliff Mayor Bruce Kennedy said Glen Cove was breaking a written agreement it signed in 2000 that limited building heights to 65 feet and the total size of the development to 700,000 square feet.

Along with the suit dismissals, the Glen Cove City School District Board of Education voted 5-1 on Thursday evening to approve a payment-in-lieu-of-taxes funding mechanism that allows the Garvies Point development to proceed. It was the final approval, after the city, its industrial development agency. Its community development agency, the Glen Cove Public Library Board of Trustees and Nassau County Legislature previously voted in favor of the same PILOT funding plan.

Construction on the first phase, which includes 28 acres of public open space, waterfront parks and esplanades, restored wetlands, an educational ecology pier and other amenities, will begin “in the coming weeks,” according to a written statement from RXR Realty, which is partners with Posillico in the project’s Glen Isle Partners development entity. The first phase is slated to be completed in about 24 months from the start of construction.

“We applaud these actions, which together are an important milestone for Garvies Point and signify that the $1 billion plan to restore Glen Cove’s waterfront to productive use for the community is underway,” Scott Rechler, RXR chairman and CEO, said in the statement. “We appreciate the tremendous support we have received from Glen Cove residents, as well as the input and guidance provided by Mayor Spinello, the planning board and the City of Glen Cove, whose diligence, thoughtfulness and commitment to getting this right has resulted in the best possible plan for this community. Today is a great day for Glen Cove, and we look forward to getting this project and its 28 acres of public open space built.”

The project is expected to generate about $400 million in net tax revenue along with an estimated annual economic benefit of $50 million to the city, including $24 million a year in local spending by new residents and the creation of more than 540 permanent jobs, according to the statement.