It is hereby declared (a) that the providing of safe and sanitary dwelling accommodations for persons of low income are public uses and purposes for which public money may be spent and private property acquired and are governmental functions of state concern and (b) that it is in the public interest that work on projects for such purposes be commenced as soon as possible in order to relieve unemployment which now constitutes an emergency; and the necessity in the public interest for the provisions hereinafter enacted, is hereby declared as a matter of legislative determination.