Dissolved solids

Overview

Dissolved solids commonly are used as a general indicator of water quality. Dissolved solids usually are composed of major ions; calcium, magnesium, sodium, chloride, sulfate, and alkalinity originating from decomposition of soils and rocks. Large dissolved-solids concentrations can make water cloudy and give it a bitter taste. In addition, water with large dissolved-solids concentrations can produce scaly deposits and cause staining, wear, corrosion of pipes and fittings.

Water-quality standards and criteria are developed by the States, approved by the U.S. Environmental Protection Agency (USEPA), and then promulgated (passed into law) as standards by each State. Graphs on this website allow comparison of measured and computed data to these standards and criteria by plotting them as straight lines. When evaluating data to decide whether water quality is suitable for the intended use, viewers are cautioned to consider the uncertainty associated with these computed data.