ABSTRACT
“Stable” water, as discussed in this chapter, refers to water that will neither compromise the water reticulation system through excessive precipitation of solids on the inside of pipes nor damage the system through chemical attack or corrosion. The stability and buffer capacity of natural waters are largely controlled by the carbonic system. Groundwater reaches its own equilibrium with surrounding rocks and sand in the aquifer, often at pressures and temperatures quite different than on the surface. Water must have a certain minimum buffer capacity before it can be safely distributed. Water hardness is caused by divalent cations, predominantly Ca and Mg. Too much hardness causes domestic problems such as soap and shampoos that do not lather and scale formation in household devices. Industrially, it has severe economic consequences because of equipment damage and the need for frequent cleaning.
