Well Water Safety
Water Treatment Devices
Method |
Uses |
Limitations |
Comments |
|---|---|---|---|
Chlorination |
Kills bacteria and viruses Can be used to remove some forms of iron, as long as water is filtered after chlorination |
Needs filtration to remove microbes shielded or embedded in dirt particles, including parasites |
Needs careful handling of chlorine, testing of chlorine levels, and maintenance of dosing pump |
Ultra-Violet |
Kills bacteria and viruses |
Needs filtration to remove microbes embedded in dirt particles, including parasites |
Needs very fine (5 micron pre-filter), slow water flow, UV lamp must be kept clean |
Filters |
Use ceramic candle filters to remove bacteria and parasites, but not viruses Use other filter types to remove sand, sediment, rust and particles Use specially rated filters to remove very small particles |
Need chlorination in addition to ceramic candle filters to remove viruses |
Need regular maintenance and replacement for proper operation |
Reverse Osmosis |
Removes nitrates, sulphates, hardness, most microbes, dirt particles and small amounts of some pesticides |
Can result in plugged membranes due to hard water |
Is costly because of need to replace membrane Needs pre-filtration and softening of hard water |
Ozonation |
Kills most microbes, but not cryptosporidium Removes organic compounds, including pesticides Can be used in combination with activated carbon filters |
Needs filtration to remove microbes embedded in dirt particles, including parasites
|
Varies in effectiveness depending on application and manufacturer |
Activated Carbon
Contactors |
Remove small amounts of some chemicals Used for removing tastes and odours, and reducing trace levels of organic chemicals (e.g., pesticides) |
Are not suitable for removing minerals, or larger amounts of chemicals |
Must be replaced regularly but hard to know when contactors are exhausted Can become a dangerous source of bacteria, taste and odour problems |
Distillation |
Kills all microbes by heat Removes heavy metals and nitrates Often used in combination with activated carbon filters |
Can remove only chemicals (e.g., fluoride, iron, nitrate) with a higher boiling point than water |
Needs regular de-scaling and weekly disinfecting with bleach or heat Can concentrate chemicals(with boiling points lower than water) in distilled water (e.g., ammonia) |
Softeners |
Reduce hardness that produces lime deposits on dish-washed items, and gives a starched effect on laundry |
Need periodic replacement of softener salt and disposal of concentrated salty water |
Needs periodic replacement of softener salt and disposal of concentrated salty water |

















