Water Hardness

Water hardness is due to the presence of certain dissolved minerals, calcium and magnesium compounds, which give the water two-well-known characteristics: the minerals will react with soap to produce a sticky, gummy deposit called “soap curd,” and when the water is heated, the minerals can form a hard, rock-like scale which may reduce the flow in water pipes and slow down heat transfer in water heaters and boilers.

All-natural water supplies contain at least some hardness, in amounts ranging from traces to several hundred grains per gallon.* In most areas, the hardness concentration is between 3 and 50 grains per gallon, and in 85% of the United States, the local water supplies contain enough hardness to cause significant problems in-home uses.

Introduction

Water hardness is due to the presence of certain dissolved minerals, calcium and magnesium compounds, which give the water two-well-known characteristics: the minerals will react with soap to produce a sticky, gummy deposit called “soap curd,” and when the water is heated, the minerals can form a hard, rock-like scale which may reduce the flow in water pipes and slow down heat transfer in water heaters and boilers.

All natural water supplies contain at least some hardness, in amounts ranging from traces to several hundred grains per gallon.* In most areas the hardness concentration is between 3 and 50 grains per gallon, and in 85% of the United States, the local water supplies contain enough hardness to cause significant problems in home uses. The Water Quality Association classifies water supplies as follows:

SOFT WATER0-1 GRAINS PER GALLON
Slightly Hard Water1-31/2 Grains per Gallon
Moderately Hard Water31/2-7 Grains per Gallon
Hard Water7-101/2 Grains per Gallon
Very Hard WaterOver 101/2 Grains per Gallon

When hard water is used in the home, it interferes with virtually every cleaning task, from bathing and personal grooming through dishwashing and laundering. Both soaps and synthetic detergents are affected by water hardness, which increases the amounts of cleaning agents needed, and produces poorer cleaning results.

When soaps are used in bathing and grooming, a film of sticky soap curd remains on the skin, and may hold particles of soil and bacteria, protecting them from removal. The soap curd interferes with the return of the skin to its normal slightly acid condition, and may lead to irritation and infection. Soap curd mon the hair makes it dull, lifeless and difficult to manage and arrange.

Even when synthetic detergents are used in dishwashing and laundering, hardness interferes. The active ingredient in the detergent mixture is partially inactivated by hardness, even though the product of the reaction stays dissolved. The alkaline “builders,” added to the detergent mixture, to “cut” greases and oils, can react with these greases and oils to form soap, which in turn can produce soap curd when hardness is present in the water. Again, the deposits can protect soil and bacteria and interfere with thorough cleaning.

*The Grain per Gallon is a common basis for measuring hardness and certain other minerals in the United States. A grain weighs 1/7000th of a pound, and originally was based on the weight of a dry grain of wheat. A common aspirin tablet weighs about 7 grains, including binders. Thus one aspirin tablet dissolved in 1 gallon of pure water would produce a concentration per gallon.

Cleaning Tasks

Numerous studies have been made of laundering with both soaps and synthetic detergents by universities and laundry product manufacturers. The table below from one of these studies shows the concentrations of soaps and synthetic detergents (synclets) recommended for maximum soil removal.

 SOAPSYDNET
Water Hardness (gpg)% Conc. for Max. Soil RemovalOz. Advoir per 15 Gal. Washer2% Conc. for Max Soil RemovalOz. Advoir per 15 Gal. Washer 2
0-20.15-0.203-40.25-0.305-6
7-100.25-0.305-60.30-0.356-7
20-300.40-0.508-100.40-0.508-10

Soil removal in soft water is significantly higher than in hard water no matter how much soap or detergent is used. In one study conducted by an independent laboratory, soil removal ranged from 50% to 250% greater with soap, depending upon the concentration. With detergents and soft water, the soil removal was 30% to 50% greater than with hard water, again depending on the concentration of detergent used. Unremoved soil causes the graying of white fabrics, and the loss of brightness in colors.

As the deposits accumulate with repeated laundering, they also contribute to the stiffening and matting of the fabric fibers. A study made by the Chicago Y.M.C.A. Laundry showed that the life of cottons and linens is reduced significantly by laundering in hard water. In this test, bed sheets, pillow slips, bath towels and napkins washed in ion exchange softened water lasted from 15% to 39% longer than those washed in water with 71/2 to 8 grains of hardness.

Hard water also adds substantially to the other cleaning tasks in the home-thering around the bathtub, the spotting of glassware, chromium and sinks. On the other hand, softened water makes all cleaning tasks easier. A quick rinse or once-over wiping eliminates spots and stains on plumbing fixtures, sinks, floors, windows and woodwork. A study at Ohio State University showed that softened water cut the time required for housecleaning from almost four hours to two hours and 21 minutes – a savings of over 10 eight-hour working days per year. Scale formation when hard water is heated is one cause of water heater failure. As a form of rock from which the hardness was originally dissolved, hard water scale is a poor conductor of heat. Thus the heat is not transmitted to the water as rapidly as it is applied, and the temperature of the metal builds up, leading to possible premature failure. Since so much heat is lost in this process, wasted fuel adds to the costs of hard water.

Water Softeners

Pipes filled with scale not only reduce water flow, but ultimately must be replaced. Fortunately, these problems may be reduced or eliminated with the installation of a water softener in the cold water line where it enters the home. This equipment uses “ion exchange” to remove the hardness minerals and certain other contaminants from the water. The equipment contains a bed of permanent softening material in the form of small granules or beads which are initially charged with sodium ions. As the hard water passes through the bed, the calcium and magnesium which cause water hardness are attracted to the softening material and held. At the same time, a chemically equivalent amount of sodium is released into the water.

This ion exchange process, as chemists call it, occurs literally billions of times during the softening process. Eventually so much hardness accumulates that the initial supply of sodium is depleted, and the bed of softening material is considered “exhausted.” Water passing through a softener in this condition would retain much of its hardness, and recharging or regeneration is necessary.

To prepare the softener for further service, brine (a strong solution of common salt) is flushed through the bed. This drives out the accumulated hardness and replaces it with sodium. After the hardness and excess brine are rinsed down a drain with fresh water, the renewed softening material is once again ready to remove hardness from water.

In using this method, it should be noted that the flow rate required for fixtures or outlets which are likely to impose continuous demands during periods of heavy use of the listed fixtures, such as hose connections, air conditioning units, etc., should be estimated separately and added to the demand for fixtures used intermittently, in order to estimate total demand.

Further, the curves in this section are not intended to estimate rare peak flow requirements, but to cover normal flow variations. However, occasional leakage of hardness into the treated water due to unusual high flow requirements will not present major difficulties in the normal installation.

Fixture or GroupType of Supply ControlWeight in Fixture Units
Water ClosetFlush Valve6
Water ClosetFlush Tank3
LavatoryFaucet1
BathtubFaucet2
Shower HeadMixing Valve2
Bathroom GroupFlush Valve for Closet8
Separate ShowerMixing Valve2
Kitchen SinkFaucet2
Laundry Trays (1-3)Faucet3
Combination FixtureFaucet3

Softening Requirements

This softening-regeneration cycle can be repeated almost indefinitely, over many years of service in the home. Most modern water softeners use either a timer or a sensing system to automatically initiate the regeneration process. A separate brine tank holds the salt for multiple regenerations and dissolves the salt for use as needed. Thus the homeowner need only add salt to the brine tank periodically to insure a constant supply of softened water.

Water softener capacities are given in terms of the number of grains of hardness they will remove between successive regenerations. The number of gallons softened between regenerations is calculated by dividing the rated capacity (in grains) by the number of grains of hardness in one gallon of water. The following table shows how this works out.

Hardness of Water Supply in Grains per Gallon (gpg)Rated Capacity of Softener in Grains of Hardness Removed
10,00020,00030,000
5200040006000
10100020003000
1566713332000
2050010001500
30333667100
50200400600

Gallons of Water Softened Between Regenerations

An average family uses about 70 gallons per person per day for all water uses in the home, or about 50 gallons per person per day if hard water can be supplied to toilets. In selecting a softener for a home, it is usually recommended that it has enough capacity to last at least three days between regenerations. The following example shows how these various factors can be used.

Let us assume that we have a family of four persons, the water has 20 grains per gallon of hardness, and all the water is to be softened. We can then figure:

4 persons x 70 gallons per day x 20 grains per gallon x 3 days equals 16,800 grains minimum softener capacity

A second factor to be considered is the peak flow rate required in the home. The following table and graph (see next page) can be used to estimate the peak flow in a home, based on the various fixtures which are to be supplied with softened water, assuming all were being used at the same time.

Guidelines for estimating Flow Rate Requirements

The estimated flow rate requirements for plumbing fixtures used intermittently on a water supply line may be obtained by multiplying the number of each kind of fixture supplied through that supply line by its weight from the above table, adding the products, and the referring to the appropriate curve with this sum. (See the Flow Rate/Fixture Unit Graph on next page).

Finally, any softener selected should carry the Gold Seal of the Water Quality Association. It is your assurance that the equipment has been tested against rigid voluntary industry performance standards, has successfully passed these tests, and has been Validated by the Water Quality Association. This Association is an industry organization of equipment manufacturers, suppliers and dealers in the industry, and is dedicated to public education in the field of water quality.

IMPORTANT: The determination of which treatment method is best should be made only after careful consideration of many factors such as economics, water quality characteristics, the end use to which water is to be put, temperature variances of the water to be treated, the inherent limitations of the available treatment technology, and others. This determination can best be made by your local water treatment representatives and they should be consulted prior to the purchase and installation of any water treatment equipment.

Hard Water Problems

The Facts on the Cost of Hard
& Mineral Contaminated water from:

Good HousekeepingNew Mexico State University
Health & Welfare CanadaMacleans Magazine
Total out of pocket cost for: 
One Month$100.00
One Year$1200.00
Two Years$2400.00
Three Years$3600.00
Four Years$4800.00
Five Years$6000.00
Ten Years$12000.00
Twenty Years$24000.00
Bacteria, H2S and minerals cause unnecessary wear and plugging of plumbing and related appliances.Minerals, tastes and odors compel people to use more coffee, cream, sugars and juice mixes to overcome the tastes in the water.
Dryness and irritated skin are a common complaint that can be related to minerals in the water.Minerals cause clothes to wear 20% - 40% faster. In the case of Denim or jeans it is 50% faster.
For every "1" grain of hardness there is 15 lbs of dissolved rock that pass through your lines every year.Staining, water spots and products are made inefficient by the mineral content in your water cause excessive use. ie: Laundry detergent is 1 lb soap to 4 lbs of softener to deal with the minerals.
Remember, Good Water Treatment is an Investment that pays you back, unlike so many things that cost you and give you no return.

“Hard Water” accounts for most of the water problems in your home

Hardness is caused by calcium and magnesium carbonate in your home’s water supply. You see the effects of hardness every day:

  • Pipe Scaling Hard water deposits a rock-like scale in pipes – causing corrosion, leaks, restricted water flow and reduced water pressure.
  • Water Heater Hard water forms rock-like scale faster. Scale builds up on the heater element, reducing efficiency and shortening appliance life. According to a recent study by New Mexico State University, soft water can save 22% in water heater energy costs.
  • Fixtures Scale clogs and erodes working parts of plumbing fixtures and appliances often resulting in expensive repairs or replacements.
  • Skin and Hair Scale forms on skin and hair too, dulling the complexion, irritating skin and contributing to hair problems. Soft water is recommended for keeping hair and skin healthy.
  • Glassware and Dishes Soap curds with hard water causing spotting of tableware. Hard water increases soap and chemical costs and seriously affects automatic dishwasher operation.
  • Clothes Hard water dulls colors, makes towels and clothes feel stiff and scratchy and requires use of harsh soaps and chemicals, thus reducing fabric life. Washer manufacturers recommend soft water to lower maintenance costs and increase appliance life.

Analyzing Your Water Hardness

Almost ALL water supplies contain varying amounts of mineral hardness. Hardness is comprised of dissolved naturally occurring substances such as calcium, magnesium and iron and is measured in grains per gallon. The table below is from the United States Department of the Interior and is the standard used to classify water hardness.

Hardness LevelClassification
Less than 1 Grain per GallonConditioned
1 to 3.5 Grains per GallonModerately Hard
3.5 to 7 Grains per GallonHard Water
7 to 10.5 Grains per GallonVery Hard
Over 10.5 Grains per GallonExtremely Hard

Soft Water Savings

“Conditioned Water” saves you money and eliminates frustration

Hard water problems are solved by using professionally installed conditioning equipment which removes hardness minerals through the use of activated ion exchange resins.

You see the effects and realize the cost savings of conditioned water immediately:

  • Save Soap – Up to 70% Plus – more efficient cleaning saves you time
  • Save Appliances – Up to 25% Consider maintenance, depreciation and replacement
  • Save Clothing – Up to 33%
  • Skin and Hair Scale forms on skin and hair too, dulling the complexion, irritating skin and contributing to hair problems. Soft water is recommended for keeping hair and skin healthy.
  • Save Energy – Up to 22% 22% for gas water heaters, 17% for electric water heaters
  • Additional Savings Bar soap, shampoos/rinses, razor blades, bath oils, skin creams, etc.

*22% BTU savings with gas heaters, 17% BTU savings with electric heaters. Source: Water Quality Association bulletin 18/80

**Sources Include: Water Quality Association, American Water Works Association, U.S. Department of Agriculture, American Home Economics Association and other recognized authorities. Results may vary depending on specific appliances and conditions.

How much are YOU spending each month for personal care items and cleaning supplies?

WEEKLY GROCERY BILLYOUR WEEKLY SOAP COSTS ARE BETWEENYOUR MONTHLYS OAP COSTS ARE BETWEEN
$60$7.14$8.52$28.56$34.08
$70$8.33$9.94$33.32$39.76
$80$9.52$11.36$38.08$45.44
$90$10.71$12.78$42.84$51.12
$100$11.90$14.20$47.60$56.80
$110$13.09$15.62$52.36$62.48
$120$14.28$17.04$57.12$68.16
$130$15.47$18.46$61.88$73.84
$140$16.66$19.88$66.64$79.52
$150$17.85$21.30$71.40$85.20

Do you feel that your family’s soap costs are on the high end, low end or in the middle of their survey?

Why Own a Softener?

This is how much hard water can shorten the life of your water using appliances and fixtures:

PERCENTAGE REDUCTION IN LIFE EXPECTANCY ATTRIBUTED TO HARD WATER
Toilets70%
Water Heaters50%
Faucets40%
Dishwashers30%
Clothes Washer30%

WATER HEATING ENERGY SAVINGS

Percentage Increase in energy consumption:
Gas 1/4 inch scale29.5% savings soft water
Electric 1/4 inch scale21.7% savings using soft water
*Study done by New Mexico State University, confirmed by Batteles Columbus Division engineers.
"Maytag, G.E., Whirlpool, Speed Queen, Hot Point and Kitchen Aid recommend soft water as ameans to help washers perform better and last longer."

QUICKER CLEANUP

Soft water gets rid of the hardness that causes the ugly film and build-up in your bathtub, sink and shower. According to a study done by Ohio State University, you can cut house cleaning time by one-third with the help of soft water. That’s over 10 eight hour days per year!

WHITER, BRIGHTER, LONGER LASTING LAUNDRY

According to a study by Perdue University, clothing life can extend by 15%.

THE COST OF YOUR CLEANING SUPPLY BILL CAN BE SLASHED BY UP TO 80%!

Why Own a Softener? It Only Makes Sense!