Types of Water
By: Derek Brown
Salt Water typically contains about 3.5% sodium chloride (or salt), although in some areas the salinity may be weakened by fresh water or more concentrated by evaporation in others. Salt water is typically more corrosive than fresh water because of the higher conductivity and the penetrating effect of the chloride ions through surface films on a metal.
Brackish Water contains between 1 and 2.5% sodiium chloride. This comes from either natural sources around otherwise fresh water or by dilution of seawater. Brackish water differs from open seawater (salt water) in certianother respects. The biological activity can be modified by higher concentrations of nutrients. As a consequence of the greater availibity of nutrients, fouling is likely to be more severe.
Fresh Water usually either comes from a surface or ground source, and will contain less than 1% sodium chloride. It may be either hard or soft, meaning it is rich in calcium and magnesium saltsand thus possibly forming insoluble curds with ordinary soap.