(a) Each authority, when created, and the members thereof, shall constitute a public corporation and, as such, shall have perpetual succession, may contract and be contracted with, may sue and be sued, and may have and use a common seal.
(b) The exercise of the powers and performance of duties provided for in this chapter by each authority are declared to be public and governmental functions, exercised for a public purpose and matters of public necessity, conferring upon each authority governmental immunity from suit in tort.