Section 2. The department may from time to time designate 1 or more areas of a gateway municipality as an HD Zone and take any and all actions necessary or appropriate to such a designation, upon receipt of a municipal application requesting such designation and representing in its application that the municipality, based on its own independent investigation, has determined that the area proposed for designation has a need for multi-unit residential properties. The application shall include a plan which shall include a detailed description of the construction, reconstruction, rehabilitation and related activities, public and private, contemplated for such zone as of the date of the adoption of the zone plan.