Perceptible Water Quality Issues
Your senses are the primary diagnostic tools in determining water contamination. At times, you can see, taste, and smell it. The color of the water gives you an idea as to what the main causative agent is. Iron, rust, or other contaminants may turn the water red, orange, yellow, brown or cloudy. Yellow and brownish water hues may be due to the tannins from decaying vegetation.
Signs of water issues include:
Bad Taste & Smell
Cloudiness & Discoloration
Signs of impurities can be identified from the foul-smell and bad water-taste. Below are the common problems encountered regarding water odor and taste:
Presence of hydrogen sulfide is suspected when the water has a distinctive rotten-egg or sulfur smell and taste. This is caused by a certain kind of water bacteria. Furthermore, sulfates make the water salty. It is important to determine the causative agent such as bacteria that may grow in drains, water heaters, wells, or on the pipes.
Decaying organic matter and dissolved solids gives a musty and earthy taste as well as smell which may originate from the plumbing or to the source of water itself.
The chlorination treatment process gives a smell and taste of chlorine. However, it is used to disinfect water to make it safe for drinking.
The byproducts of gasoline, refining, paints, detergents, or inks give the water a smell and taste like turpentine. Other chemicals may indicate the presence of methyl tertiary butyl ether (MTBE) or xylenes.
Contamination of mercury, lead, copper, arsenic, iron, manganese and zinc in the water makes it taste and smell metallic. This kind of contamination may originate from the pipes.
Hard water can be indicated through scale deposits.
Water hardness ( or hard water) contains certain amounts of calcium, magnesium, and other divalent and trivalent metallic elements which is a common quality of water.
Hardness is the term originally coined to waters that were hard to wash in. This refers to the hard water soap wasting properties. An insoluble curdy precipitate in water is formed from preventing the hard water and soap to lather. Hardness scale (such as in cooking pans) is usually caused by the hardness of water as well. A number of problems in laundry, kitchen, and bath resulted due to the production of scales in pipes and water heaters originating from the accumulation of dissolved calcium and magnesium The unit for expressing hardness is in grains per gallon (or ppm) as calcium carbonate equivalent.
What is Soft Water?
The American National Standards NSF/ANSI 44 and NSF/ANSI 330 defined soft water as the water that contains <1 grain of hardness per gallon (or <17.1 mg/L hardness).
Hard Water indications:
Stiff, dingy laundry
Dishes and glassware mineral deposits
High soap usage & need for fabric softeners
Bathtubs & shower stalls accumulation of soap curds
Scale build-up in pipes and on appliances leading to high energy costs
Scale build up in sinks, tubs, faucets & appliances
Issues on water hardness can be treated to improve the usability of the water.
Softening Water for the Fixtures and Appliances
The fixtures and appliances of homes and businesses are greatly affected by the scale deposits which are created from the hardness buildup. Due to this, hardness water treatment of the whole houses and buildings are done rather than just at a specific faucet. The minerals produced from the hardness can be minimize and the water turned “softer” by any of the following methods:
Chemical softening - examples of chemical softening would be lime softening, hot and cold; lime-soda softening. Essentially it is the process of removing calcium and magnesium that causes hardness in water by using chemical reactions.
Membrane separation softening - Also known as Nano filtration, this is a pressure driven filtration process through a semipermeable membrane where the pores are large enough to let water through but leave calcium and magnesium behind.
Cation exchange softening - Removes magnesium ion by exchanging them with sodium or potassium ions. Cation exchange softening can be inorganic, carbonaceous, or organic base exchangers.
Anion Exchange - similar to cation exchange softening but utilizes Anions or negatively charged ions.
Stains on Plumbing Fixtures
What causes discoloration on sinks, tubs, and toilets?
Corrosion of copper within the household plumbing can be observed when the water turns to blue-green in color. Yellow, tan, brown, black, orange, or red are color indicators of the presence of metals aside from copper. Iron makes the water reddish and yellow-tan while manganese produces white black or dark brown colors. The two metals, iron and manganese, frequently come together due to their similarities. That is why, these elements are treated in the same manner.
A process known as oxidation happens whenever a certain type of metal is exposed to oxygen, thus making a discoloration to the water. The water in the plumbing system has limited exposure to oxygen. Therefore, the water is able to maintain the soluble metals, iron (ferrous) and manganese, in solution. Visible water stains can only be observed once the water comes out of the tap. The color changes occur when there is air exposure because of the processes it undergoes like chemical reaction and oxidation.
Low concentrations of these metals at about 0.3 parts per million (ppm) of iron or 0.05 ppm of manganese may result in water stains but may appear clear when coming out of the faucet because the stains stayed on the plumbing system.
Some kinds of bacteria prefer iron and manganese rich waters. Although these bacteria may not be pathogenic, they can still cause an undesirable effect by clogging and slowing down the water flow of pipes and plumbing systems to the appliances at home.
Taste & Odor Issues
Foul smell of water can be noticeable around the house or office while taste issues can only be observed when the water is used for drinking. The type of water treatment for the whole house or building can be determined depending on the extent of faucets affected.
Here are some of the water treatments that help reduce contaminants of the water that causes it to taste and smell bad. Any or multiple of these treatments can be applied:
pH adjustments higher or lower
Cloudiness & Discoloration Issues
The discoloration in water may also indicate impurities and makes the transparency of the water turbid. The amount of small particles and solid matter that suspends in water is called turbidity and is measured by the amount of scattering and absorption of light rays caused by the particles. The turbidity makes the water appear opaque due to the blockage of light rays. The unit of measurement of turbidity is in nephelometric turbidity units (NTU). For water to be considered as potable, turbidity should not exceed 0.5 NTU. The water’s turbidity is not directly proportional to solids that are suspended because the white particles reflect more light than dark-colored particles and many small particles will reflect more light than an equivalent large particle.
The gradual decomposition or destruction of a material by oxidation or chemical reaction is known as corrosion. Most of the time, it is caused by an electrochemical reaction. It starts at the surface of a material towards the inner part. Rusting is the term used to describe the corrosion of iron.
Below are the factors that accelerate corrosion:
Acidity (low pH)
High mineral concentrations
Stray current electrolysis
Galvanic corrosion caused by dissimilar metals
Dissolved oxygen content
Water treatment can improve corrosion issues. The following types of water treatment solutions are recommended:
Limestone chip filters
Soda ash feeds
Phosphate solution feeds
Silicate solution feeds
Although it is a good idea to have your water quality tested through various scientific instruments, even your sense of sight, smell, and taste are enough to detect issues in water quality. Now that you know what problems are associated with certain tastes and smells in water, the next time you encounter them consult this post. Try to see if it fits the description of some of the water quality problems mentioned.