On this page of the Cyberpunk 2077 game guide you will find out whether you can get to the Arasaka Waterfront. It is one of the Night City districts and you may be interested in it if you plan to explore 100% of the world map.
As a reminder, Arasaka Waterfront is located in the northern part of the world map. It is one of the Watson subdistricts.
According to its name, the entire area is controlled by the Arasaka Corporation. It is used for logistics, storage and manufacturing purposes.
The entire district of Arasaka Waterfront is unavailable to the public, i.e. to those who are not employees of the Arasaka Corporation. This also applies to V - you will not be able to freely explore this area. There are heavily guarded checkpoints at all entrances to the waterfront area. Even if you manage to defeat the enemies supported by mechs and bots, you will not be able to get inside. Cyberpunk 2077 offers no playable aerial machines, so you won't be able to over the wall either.
What may be consoling is that there are no quest markers, gems nor stores in the Arasaka Waterfront area anyway. At most, you might stumble upon individual attractions as you move along the wall surrounding the waterfront. V can find, among other things, one of the murals/graffiti to scan.