It is hereby declared that unsanitary or unsafe dwelling and public school accommodations exist in various counties of the state and that such unsafe or unsanitary conditions arise from overcrowding and concentration of population, the obsolete and poor condition of the buildings, improper planning, excessive land coverage, lack of proper light, air and space, unsanitary design and arrangement, lack of proper facilities, and the existence of conditions which endanger life or property by fire and other causes; that in all such counties persons of low income are forced to reside in unsanitary or unsafe dwelling accommodations; that in various counties of the state there is a lack of safe or sanitary dwelling and public school accommodations available to all the inhabitants thereof and that consequently persons of low income are forced to occupy overcrowded and congested dwelling accommodations; that these conditions cause an increase in and spread of disease and crime and constitute a menace to the health, safety, morals, and welfare of the citizens of the state and impair economic values; that these conditions cannot be remedied by the ordinary operations of private enterprises; that the clearance, replanning, and reconstruction of the areas in counties in which unsanitary or unsafe housing conditions exist and the provision of safe, sanitary, and uncongested dwelling accommodations at such rentals that persons who now live in unsafe or unsanitary or congested dwelling accommodations can afford to live in safe, sanitary, and uncongested dwelling accommodations, are public uses and purposes for which public money may be spent and private property acquired; that it is in the public interest that work on such projects be instituted as soon as possible in order to relieve unemployment which now constitutes an emergency. The necessity in the public interest for this article is hereby declared as a matter of legislative determination.