Is Softened Water Good for the Environment?

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As the process of turning hard water into soft water involves chemicals, there is
naturally a concern for the environment and the possible damage this causes to
the surrounding ecosystem. In any case, an artificial chemical process is the
human method of controlling a set of components into a specified form for a
number of practical reasons. Typically, chemicals are used to enhance the
original form of the substance with the aim of improving the quality of the end
product, e.g. bleaches for cleaning, preventing damage to humans and removing
threats. In the instance of softened water, the process is to prevent hard water
damaging expensive and valuable appliances installed in the home.
To explore this issue further, the difference between hard and soft water must be
understood to identify if softened water has a detrimental effect on the
environment, and, most importantly, is it beneficial for us to drink and use in
daily life?

The terms `hard water' and `soft water' are both common terms used in
everyday life, but what exactly is the difference between the two? Hard water is
typically defined by possessing a high level of dissolved mineral content,
specifically calcium (Ca) and magnesium (Mg). This is the result of a natural
process as water transports through soil and rock, dissolving small amounts of
minerals and suspends them in solution. Calcium and magnesium are the most
common minerals that result in water becoming 'hard' and the level of hardness
becomes greater as the mineral content increases.
`Hard water' is simple to distinguish as it does not produce lather when in
contact with soap, shampoo or washing liquids. The implication of this is the
inability to wash properly, whether that may be washing the skin or
kitchenware. At high temperatures, the magnesium and calcium react,
producing a hard slimy white substance commonly known as `lime scale'. This
is particularly bad for domestic appliances, such as kettles and boiler elements
and can cause huge problems in industrial settings. The direct result of this
build-up in limescale is that everyday appliances become less energy-efficient,
costing the owner financially. British Water state that even 1.6mm of scale in
heating systems causes a 12% loss in heat transfer from the energy source to
water. This causes the heaters and boilers to run longer and hotter, using more
gas or electricity, resulting in a higher running cost. However, because hard

water is full of minerals, it is often sought after for its unique properties and
health benefits e.g. mineral-rich springs such as those in Bath, England are
internationally renowned.
`Soft water' is regarded as treated water as it is free of the mentioned minerals,
making household chores easier and lower energy bills. Through the use of a
water softener, it's possible to change the properties of hard water into soft
water. The hard water passes through a tank containing resin beads holding
`soft' sodium ions. The `hard' calcium and magnesium ions are exchanged for
sodium ions, thus softening the water, with the sodium or potassium ions
passing down through the resin bed and out the softener's drain.

The most common concern for the environment when using a water softener is
the discharge of salt brine into the wastewater collection system. This by-
product of the water softener can ultimately have a negative impact on recycled
water and wastewater discharge. However there is a strong argument that this
by-product can easily be drained into a separate tank and treated.
Another concern is the increase in sodium content. Although this is great for
producing soft, kind to the skin goods such as bath robes, lather from soap and
reduced risk of damage to appliances, there are some other areas of contention.
These can range from the use of soft water in fish ponds and aquariums, and
whether or not it is safe for pets to drink such fluids.
It is commonly discussed that soft water is beneficial in treating skin conditions
such as eczema, and there are a wealth of studies conducted by well-respected
bodies such as the National Eczema Society which support this theory. It is
difficult to state whether that this is due to the type of water and the overall
benefits on the skin.

To conclude, the overall impact of softened water on the environment is not
detrimental, particularly as the use of a separate tank to collect the salt brine
removes any possibility of treated water having a harmful effect on the local
environment. Furthermore, this reduces the likelihood of transporting treated
water any further and therefore impacting on the local ecosystem. Humans

realise the benefits of softened water due to the reduction of lime scale and the
impact this can have on the efficiency of domestic appliances and reduced
running costs.
About the author: Mike Sutton has become increasingly interested in realising
the benefits of water softeners through EcoWater and understanding the impacts
on the environment.