The new map surprisingly includes three districts -- Muzaffarabad, Punch and Mirpur -- which are under Pakistan occupied Kashmir (PoK).
The solidarity rally will come during Imran Khan's day-long official visit to Muzaffarabad on Friday.
Tensions have been simmering between India and Pakistan ever since New Delhi on August 5 revoked the special status of Jammu and Kashmir .
Locals said that the water of Neelum and Jhelum rivers has been diverted for the plant which has triggered a water scarcity in the region, affecting their day-to-day lives.
The issue is also now being linked to the LoC trade, which India suspended about three months back.
The residents of Muzaffarabad now want that river water levels should be restored to internationally set standards.
Delhi and others have tried multiple times to get the UN Security Council to declare Azhar a global terrorist, including in 2016 and 2017.
It is the same district where in early 2000 Mukhtaran Mai was raped on the order of the village council, triggering an international outrage.