The Barsilai Lake is a large, freshwater lake, from which the wide and fast-flowing River Sormaros flows south, eventually delving into Danetha and joining with the River Bjuane. The lake is known to be a good spot for fishing, and half of Brimsail's fishing trade goes towards lake fishing on the Barsilai, while the other is dedicated to sea fishing.
Barsilai Lake is wide and deep, but is not untraversable. There is a strip of land about a mile or two across the separates the lake from the sea, and this can be used to go round and, indeed, to get from Western Nareikk to Middle Nareikk without having to cross the Sormaros, and can offer a safer journey than attempting to brave the vicious river.
In Violet Sword Blade Edit
Violet Sword Blade mentions Barsilai lake several times throughout the early chapters of the book, which take place in Nareikk, and the protagonist, Mazzek Rettensauth, goes with the Kazdriel forces and takes part in the Battle of Brimsail, an attempt at liberation of the fishing port from Danethan control, in January of 1246, AoW.
Once the Battle of Brimsail is won, the Kazdriel attempt to make their way around the lake and into Middle Nareikk, where they later pass through the town of Persinai, without crossing the Sormaros, as one of their soldiers was lost to the river on the way to Brimsail. In addition, Sornbridge, the only bridge across the river itself, was then under Danethan control, and the platoon's leader, General Martius, is cautious as to where he treads. So, plagued by rainstorms which are common in the area, the regiment skirt around the lake to the north. At another time, it may have been possible to charter a boat from Brimsail to the other side of the lake, but with the town in such disrepair, the service was likely not available.