The Lady's Dark Sea: The Deepwell

Here is the first sea that I am working on writing up.
Enjoy comments/suggestions/ideas welcome

The Deepwell Sea
The Deepwell is named after its only known direct connection with the surface a water well located in the Hive. The well may or may not still exist as it was originally in the Prime ward of the city and has seen many centuries at the least of disuse. Still the Deepwell is one of the calmest of Sigil's cavern seas with the tidal currents flowing smoothly from one end of the cavern to the other. The cavern's shape above water is similar to that of an oyster shell with the water flowing from the point to the hinge. Below it widens out and deepens considerably. Thus there is almost no natural shoreline around the rim of the Deepwell. There are however hundreds of thousands of crevices and terraces carved into the shoreline and ceiling extending back to form places for land-loving creatures to live. The water is fresh and below the tidal currents it has a constant haze of silt and sooty particles suspended in the still waters. The particles thicken as the depth increases and as well they also grow far colder.
Unlike the other cavern seas of sigil the Deepwell is thankfully pure of the razor corals and kelps that choke others. It is also one of the most active seas with several portals to various primeworld underdarks so that it is not uncommon to see barges and slave gallies plying the dark waters laden with goods from one carved outpost to another. With all this trade also comes piracy, and pirates can come at ships from below the surface, from ships, or from above either on the air or from the ceiling. Resistance is mounting and it is rumored that an Illithid empire is bringing ships over plank by plank breaking down and reassembling an entire armada to try and stamp out the pirate menace and in the process take control of the waters.