The purpose of this chapter is to promote the general welfare and economic development by empowering certain municipalities to (a) acquire or lease real property, whether located within or outside the corporate boundaries of such municipality, from the United States, (b) develop and use such real property, and (c) incorporate such real property. The provisions of this chapter are and shall be construed to be independent of, an alternative to and in addition to all existing laws of the state governing the authority of municipalities.