Is the Brisbane river salt or fresh water?

The Brisbane River is a tidal river, meaning that the water level rises and falls with the tide. The salinity of the river varies depending on the location and the time of day. In the upper reaches of the river, the water is fresh, while in the lower reaches, the water is saline (salty). The salinity gradient in the Brisbane River is caused by the mixing of fresh water from the upstream tributaries with salt water from the ocean.