Brackish water is water that is saltier than fresh water, but not as salty as seawater. It may result from mixing of seawater with fresh water, as in estuaries, or it may occur in brackish fossil aquifers. It could be byproduct of some industrial activities.
Technically speaking the TDS (Total Dissolved Solid) level in brackish water could be up to 5,000 ppm (parts per million) and 15,000 ppm in highly brackish water. It is a range of salinity levels, and not just one particular. The salinity level in brackish water may rise or come down with time.
|Water Salinity in Percent (%)
||0.05 - 3
||3 - 5