The Bila river is the largest tributary of the Laà ¡va river. The Bila river flows past the settlements of Stara Bila and Nova Bila (), with a length of approximately 35 km. Originating from Vlaà ¡iàmountain, in the area of Prelivode and Meupiàmountain, it flows south to south-east toward Laà ¡va valley where it spills into the Laà ¡va river.
The aquifer form which the source of the Bila emerges is shared with the Vrbanja, Ilomska, and Ugar rivers of the Vrbas basin in the west, and the Bosna basin in the east, via rivers of the Usora and Laà ¡va. This watershed is situated in the areal of mountains MeupiÃÂ, VuÃÂija Planina (), Usko Brdo (), Vijenac, Jasen and DiviÃÂ, at approximately 1,300 to 1350 meters above sea level. On its way to the Laà ¡va, the Bila runs through a valley between the Vlaà ¡ià(1943 m) and Meokrnje (1,425 m) mountains, which is approximately 2.5 km wide near the confluence with the Laà ¡va, passing through the villages of Bukovica and MehuriÃÂi. The river often floods the valley and has significant hydro potential.
The river Bila is rich in water as it drains from numerous small mountain rivers and streams, such as, on the right: the Suhi potok, Butetinac, Paà ¡inac, Ribnjak, Trimuà ¾a and Kozica, and on the left: the Prà ¾ni and JavoraÃÂki potok, RamiÃÂa Rijeka, Jasenica, and RogaÃÂka Rijeka.