Developer Jeff Kozero is resuming his efforts to gain city approvals for a complex of residential high-rises on land he acquired from the Sheet Metal Workers union along the Delaware River in South Philadelphia.

K4 Philadelphia LLC, for which Kozero serves as managing partner, is scheduled to present its newest plans for the Liberty on the River project before Philadelphia’s Civic Design Review board on May 7.

The appearance before the panel, which offers nonbinding suggestions on Philadelphia’s biggest development proposals as part of the city’s building-approval process, is scheduled more than 2½ years after Kozero first presented his vision for the site.

Back then, the Rockville, Md.-based developer was seeking to build 10 mostly residential high-rises and about 100 rowhouses on a site comprising nearly all the land east of South Columbus Boulevard between Washington Avenue and Reed Street.

The tract was to have consisted of 18 acres acquired in 2015 from Sheet Metal Workers Local 19, along with an additional eight-acre parcel — partly covered by a meeting hall — that Kozero had said he was negotiating to buy from the union.

The plan was put on hold the following year amid public opposition to legislation sought by Kozero that would have let his company build towers beyond the 244 feet — about 24 stories — permitted by the land-use rules that cover central Philadelphia’s Delaware River waterfront.

In the updated plans, detailed in a presentation uploaded to the Civic Design Review panel’s website on Wednesday, six towers are now proposed, all of which max out at or below the permitted 244 feet, far short of the previously envisioned heights of up to 34 stories.

Another change is that the proposed structures are now entirely situated on the 18 acres owned by Kozero’s group, sandwiched largely between the Sheet Metal Workers’ meeting house property and the river, although the plans also call for two of the towers to be built on piers that jut into the river.

The buildings will have 1,770 apartment or condo units; 232 senior-living units; 208 hotel guest rooms; and about 43,000 square feet of retail space. Both towers have parking garages on their lower levels, for a total of 1,378 spaces.

The Civic Design Review submission is most detailed in its description of the complex’s first building, a 23-story apartment or condo tower with 729 units that would rise just beside the river, set far back from Columbus Boulevard.

The Pennsport Civic Association neighborhood group will have an opportunity to comment on the proposal as part of the city’s approval process at a May 1 meeting, according to the submission.

It was yet to be determined whether the plan would require any special exceptions from area land-use regulations to proceed, according to the presentation. Stephen G. Pollock, a lawyer for the proposal, did not respond to a phone message seeking details.