CHICAGO (CBS) — A 20,000-seat soccer stadium and an entertainment district run by Live Nation will no longer be part of the $6 billion Lincoln Yards project proposed for a stretch of land along the Chicago River on the North Side.

In a statement Tuesday morning, Ald. Brian Hopkins (2nd) said he does not support the proposed soccer stadium, and has asked developer Sterling Bay to replace it with park space.

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Sterling Bay and Chicago Cubs owner Tom Ricketts had planned to build the stadium as part of the 70-acre Lincoln Yards project on the Chicago River, between Bucktown and Lincoln Park. The stadium would have had a retractable roof, and been home to a United Soccer League expansion team owned by Ricketts. It would have been used for concerts and other events in the offseason.

According to published reports, the alderman’s decision comes after conducting an online poll that found 53 percent of his constituents were opposed to the stadium, which developers want to build at what is now the city’s Fleet & Facility Management site at Throop and Wabansia. Only 23 percent of those polled supported the stadium, while 25 percent were unsure.

Hopkins also said he will not support a proposed entertainment district that would include multiple venues run by concert promoter Live Nation, with seating capacities ranging from 3,000 to 6,000. The alderman said he has asked Sterling Bay to replace the entertainment district with a mix of restaurants, theaters, and smaller venues, and he said Live Nation would not have any ownership interest in those sites.

The alderman’s support is crucial for the ambitious Lincoln Yards plan, as aldermen traditionally are given the final say on any development projects in their wards.

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However, constituents in the 2nd Ward raised concerns about the stadium’s impact on traffic.

Hopkins said the changes he requested will be incorporated into a new master site plan for the Lincoln Yards project, and will be subject to community input and review.

The project would include 12 million square feet of new buildings, including skyscrapers as high as 50 stories.

The project is expected to take 10 years to complete, if approved, so it’s possible the developers could try to convince Hopkins to support the soccer stadium later, after new roads and bridges are built as part of the larger Lincoln Yards project.

“While these recent changes to the 70 acres that comprise Lincoln Yards are intended to reflect community concerns, the process is ongoing and will continue to be refined over many years, if not decades,” Hopkins said in a statement.

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Hopkins said he is asking Mayor Rahm Emanuel to expedite plans to reconfigure the intersection of Armitage, Ashland, and Elston to ease traffic congestion in the area. The alderman said he expects planning to be completed by the end of June.