It is found and declared that there exist in the municipalities of the state substandard, insanitary, deteriorated, deteriorating or blighted areas, that the existence thereof is impairing and arresting the sound growth and development of such municipalities and is inimical to the public health, safety, morals and welfare of the inhabitants of the state, that such municipalities are unable to rehabilitate such areas without state financial assistance as provided by sections 8-154a, 8-154b, 8-154c and 8-154e, that the granting of such assistance is a public use and purpose for which public moneys may be expended and that the necessity in the public interest for the provisions of said sections is hereby declared as a matter of legislative determination.