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Water Hardness and Quality

Last Updated on Wednesday, 26 May 2010 20:04 Sunday, 10 August 2008 20:11

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Articles - General Plumbing

Many water lines contain hardness minerals (calcium and magnesium). These minerals form a scale and create problems in water lines, water heaters, washing machines, dishwashers, coffee makers, humidifiers and plumbing systems.

What is Water Hardness?

Water hardness is simply the presence of dissolved calcium and magnesium minerals in water. The actual amount of hardness in water may vary greatly. Rain water is "soft" or mineral free. But as it hits the ground and runs downward towards the underground water table, it comes in contact with limestone (calcium and magnesium rock) on its way. Since water is an excellent solvent, it dissolves amounts of calcium and magnesium. The amount of hardness in water is measured in Grains per Gallon (gpg). It’s how much hardness is present in water that determines whether or not it will be a problem. Here is a standard breakdown of hardness levels based on gpg (Grains of Hardness per gallon).

Soft = 0 - 3.5 gpg
Moderately Hard = 3.5 - 7.0 gpg
Hard = 7.0 - 10.5 gpg
Very Hard = 10.5+ gpg

If you are given a water analysis report that has hardness expressed in ppm (parts per million) or mg/l (milligrams per liter) you need to convert this to grains of hardness per gallon. You do this simply by dividing ppm or mg/l by 17.1. Example: If the analysis shows 273.6 ppm of hardness, divide that by 17.1 and you'll get 16 grains of hardness.

Iron in Water

Just like hardness, iron can build up in water heaters, piping, and all the other fixtures in your house and also imparts a metallic taste to water. Iron also leaves reddish brown stains in all your plumbing fixtures, even your laundry stains. Unfortunately, iron is a little harder to handle than just hardness. Most iron problems can be eliminated by testing the water and sizing the correct equipment to handle the job.

Other water problems

If your water has a rotten egg smell, it  indicates presence of hydrogen sulfide gas. Tannins, low pH (acid water), or any other water related problem, may require additional equipment

Content provided by Addie Water Systems