City Council President Darrell L. Clarke says he will lay out a proposal Thursday to radically restructure how the city manages planning, development and construction in Philadelphia.

His proposal calls for a City Charter amendment to create a cabinet-level Department of Planning and Development that would oversee and coordinate functions now handled by seven unrelated agencies, boards and commissions, including the Planning Commission, the Historical Commission, the Department of Licenses and Inspections, and the Housing Authority.

Clarke said his proposal has been in the works for more than a year and is unrelated to other efforts to reconsider how the city licenses and inspects buildings in light of the fatal June 5, 2013, Center City building collapse.

A blue-ribbon panel appointed by Mayor Nutter after the building collapse is to release its report Thursday. It is expected to call for getting rid of L&I and creating a safety-focused Department of Buildings, plus a second agency to handle licensing and other non-safety duties. Both would be cabinet-level.

Clarke said he did not see his proposal as necessarily negatively impacting whatever the mayor's panel recommends.

Herbert Wetzel, executive director of housing and community development for City Council, was charged by Clarke to come up with the consolidation proposal.

"This started with the Council president saying to me that there is a constant din out there from developers," Wetzel said. "They were complaining we are not coordinated. One department does not know what the other is doing. It takes forever to get things done. Can you look at other cities to see what they are doing?"

In his search, Wetzel said he looked at Cambridge, Mass.; Sacramento, Calif.; and Chicago.

"We found that other cities take a more holistic and comprehensive approach than Philadelphia," he said. "No approach is identical, but the cities we looked at all had highly integrated the sets of activities that affect development."

Under Clarke's proposal, a Department of Planning and Development would have three divisions: planning and zoning; licenses, inspections, and enforcement; and housing.

Falling under the division of planning and development would be the Planning Commission, the Historical Commission, and the Zoning Board of Adjustment. The Planning Commission and the Historical Commission are currently independent. The zoning board falls under L&I.

The division of licenses, inspections, and enforcement would include an inspections-and-enforcement unit, a licenses-and-permits unit, the Board of Building Standards, and the Board of Licenses and Inspection Review.

The housing division would oversee the Housing Trust Fund and a new body, the Intergovernmental Housing Commission, made up of representatives of the Housing Authority, the Redevelopment Authority, and the Philadelphia Housing Development Corp.

The proposal will need the support of at least 12 of the 17 Council members if it is to be put on the May ballot for a referendum. Clarke said he was confident he had the votes.