The lake sat in the middle of a city park, and was large enough to support boating.
In the late 15th century DR, Blacklake became utterly polluted by ash and debris from the eruption of Mount Hotenow in the Year of Knowledge Unearthed, 1451 DR, as well as by filth and rubbish from the refugees and vagabonds who made their homes in nearby ruined houses. It even contained several destroyed ships.