Where can I find information about Sodium in water?

Sodium

Sodium is a light alkali metal which will actually float on water in its pure state. However, it is very chemically active and is rarely found in its pure state. All natural waters contain sodium, as nearly all sodium compounds readily dissolve in water. Sodium is used primarily as sodium chloride (salt) and sodium sulphate (salt cake).
The salting of highways to control ice and snow accounts for the largest single use of sodium chloride. Significant quantities are also used in the food processing, dairy, fishing, grain, brewing, and slaughtering and meat packing industries.
Sodium sulphate is used mainly in the soap, pulp and paper, glass and glass-wool industries. It is also used in base metal smelting, as a mineral feed supplement and in the manufacturing of medicinal and industrial chemicals.

Guidelines

The Guidelines for Canadian Drinking Water Quality 1989 has not set a maximum acceptable concentration for sodium in drinking water. Sodium is not considered a toxic metal, and up to 10 grams per day are consumed by healthy adults without apparent adverse effects. In addition, the average intake of sodium from water is only a small fraction of that consumed in a normal diet.
Persons suffering from hypertension or congestive heart disorders may require a sodium-restricted diet, in which case the intake of sodium from drinking water could become significant.
It is therefore recommended that the measurement of sodium levels be included in routine monitoring programs. You should notify your family doctor when the sodium concentration exceeds 20 mg/L.

Treatment

Sodium may be removed from a water supply by the ion exchange method. The ion exchange resin in the water softener is enriched with calcium and acts to remove the sodium from the water. Other demineralization techniques, such as, reverse osmosis, distillation, electro dialysis and freeze - thaw processes, should be effective methods for the removal of sodium from the water. If a large supply of water is required, it may be necessary, if feasible, to blend it with another water source low in sodium.
In addition to water treatment, another method of sodium removal from the drinking water would require the construction or reconstruction of a water well. This frequently involves the installation of additional casing beyond the length (depth) normally required by regulation.