(a) Class I projects as defined by § 415.20 of this part shall be subject to review and approval by the Commission.

(b) Class II projects as defined by § 415.21 shall be subject to review and approval by a duly empowered state or local agency; and if there be no such state or local agency at any time on and after January 1, 1978, and only during such time, the Commission may review any such project which has been identified by the Executive Director as having special flood hazards, and:

(1) Is located along the mainstem Delaware River or a major tributary thereof, or

(2) An agency of a signatory party requests such review.