Callahan Construction has unveiled plans to build 180 market-rate apartments in six three-story apartment buildings on the large grassy lot at 380 Cedar Cross Road in Dubuque. The local developer plans to begin construction this spring pending a development agreement with the city, which likely would include tax-increment financing to help the city reduce its housing shortage. Callahan plans for a private investment upward of $20 million. The six apartment buildings each will have 17 one-bedroom apartments, 10 two-bedroom units and three three-bedroom apartments. Last week, the Dubuque Zoning Advisory Commission recommended a zone change for the 11 acres from commercial to a planned-unit development for multi-family residential.