It is hereby found and declared that there exist in many urban communities within this State conservation areas, as defined herein; that these conservation areas are rapidly deteriorating and declining in desirability as residential communities and may soon become slum and blighted areas if their decline is not checked; that the stable economic and physical development of these areas is endangered by the presence of blighting factors as manifested by progressive and advanced deterioration of structures, by the over-use of housing and other facilities, by a lack of physical maintenance of existing structures, by obsolete and inadequate community facilities and a lack of sound community planning; that as a result and concomitant of the decline of conservation areas, there is a growth of delinquency, crime, and of housing and zoning law violations in such areas, together with an abnormal exodus of families; that the decline of these areas threatens to impair the tax base of such communities and produce the conditions characteristic of slum and blighted areas which threaten the health, safety, morals, and welfare of the public; that in order to promote and protect the health, safety, morals and welfare of the public it is necessary to provide for the protection of such conservation areas and prevent their deterioration into slum and blighted areas. The granting to the municipalities of this State of the powers herein provided is directed to that end, and the use of such rights and powers for the prevention of slums is hereby declared to be a public use essential to the public interest.