Commissioners unanimously gave preliminary approval to rezone 90 acres for the proposed Rock Chalk Sports Park.

The 90-acre site just north of the northeast interchange of Sixth Street and the South Lawrence Trafficway would change from agricultural zoning to the General Public and Institutional category.

Commissioners, though, said they may withhold approving the second reading of the zoning ordinance, which must happen before it can become final, until it hears more specific details about the proposed uses for the property.

The site would house both a city recreation center and a variety of Kansas University athletic facilities. But commissioners said they wanted to hear more about proposed future uses, such as a 4,000-seat amphitheater.

Commissioners said they wanted to make sure some of the uses would be compatible with future development in the area. Some of the property directly south of the proposed sports complex site is zoned for single-family housing.