TABLE OF CONTENTS
- Turbidity
- NTU
- pH
- MCL
- Chlorine Residual
- mg/L
- ug/L
- ppm
- ppb
- Hardness
- Hard water
- gpg
- Running annual average
Turbidity – Turbidity is a measure of how dirty or cloudy water is and is measured by the amount of light that is reflected in a water sample. When light is exposed to a water sample, suspended matter will scatter light rays and the amount of light reflected is expressed as the turbidity, which is expressed in NTUs.
NTU – Nephelometric Turbidity Units, a measure of the suspended matter in water.
pH – The pH scale measures how acidic or basic a substance is. It ranges from 0 to 14. A pH of 7 is neutral. A pH less than 7 is acidic, and a pH greater than 7 is basic. A substance that is neither acidic nor basic is neutral. Pure water is neutral, with a pH of 7.0. When chemicals are mixed with water, the mixture can become either acidic or basic. Vinegar and lemon juice are acidic substances, while laundry detergents and ammonia are basic.
MCL – Maximum contaminant level. An MCL is the highest level of a contaminant that is allowed in drinking water.
Chlorine residual – Amount of free chlorine in the water which helps to prevent bacteriological activity.
mg/L – milligrams per liter.
For example, a reading of 1 mg/L expresses that there is 0.001 grams of the particular substance in 1 liter of water.
ug/L – micrograms per liter.
For example, a reading of 1 ug/L expresses that there is 0.000001 grams of the particular substance in 1 liter of water.
ppm – parts per million. ppm and mg/L are used interchangeably.
ppb – parts per billion. ppb and ug/L are used interchangeably.
Hardness – A characteristic of water caused mainly by the salts of calcium and magnesium. Hardness shown for TMWA water is given as calcium carbonate.
Hard water – Some textbooks define hard water as water with a hardness of more than 100 mg/L as calcium carbonate.
Running annual average – Compliance is determined by calculating the running annual average from the groundwater wells and the surface water treatment plants.
