Is coloured water dangerous? Not necessarily.
The main causes of water discolouration
Tannins
Tannins are organic compounds naturally present in certain soils, plants, roots, and humic matter. They can color water, much like a light infusion would.
Possible colors
- Golden yellow
- Amber
- Light brown
Is it dangerous?
No. Tannins are not toxic. They can alter the taste of water, but pose no health risk.
Common causes
- wells and boreholes near areas rich in vegetation
- rainwater collection systems or cisterns
- regions with forest or peaty soils
Rust and iron
Iron and its oxides (rust) are among the most common causes of colored water.
Possible colors
- Amber
- Light brown
Is it dangerous?
Generally, no. Iron oxides are harmless at normal concentrations, but can give water a metallic taste.
Common causes
- Stirring or pressure variations in pipes
- Aging or corrosion of metal pipes
- Deposits released after work on the network
Air in water
Suddenly whitish water is often caused by microbubbles of air.
Possible colors
- Whitish
- Milky
Is it dangerous?
No. The water becomes clear again within a few seconds, confirming that it is dissolved air, a phenomenon that has no health consequences.
How can you check?
Fill a glass and leave it to stand: if the water becomes clear within a few seconds, it is dissolved air.
Common causes
- Pressure variations in the pipes
- Work or purging on the network
- Air/water mixture in internal installations
Manganese
Manganese is a naturally occurring mineral found in certain aquifers that can darken water when it oxidizes.
Possible colors
- Black
- Dark gray
- Purplish
Is it dangerous?
In low concentrations, it does not pose a health risk. The problem is mainly visual.
Common causes
- Mineral-rich groundwater
- Manganese oxidation in pipes
- Pressure variations or work involving deposits
Limestone
Hard water rich in minerals can become slightly cloudy when agitated or heated.
Possible colors
- white
- milky
- translucent with a slight haze
Is it dangerous?
No. This phenomenon is purely aesthetic and has no impact on health.
Common causes
- water naturally rich in calcium and magnesium
- calcium carbonate precipitation during heating
- turbulence and pressure in pipes
Chemical contaminants
Certain industrial pollutants or metals can, in exceptional cases, color water in an unusual and persistent manner.
Possible colors
- blue
- green
- black
Is it dangerous?
Yes. Chemical contaminants such as hydrocarbons or heavy metals can pose a health risk and require urgent analysis.
Common causes
- infiltration of industrial or agricultural substances
- advanced corrosion of metallic materials
- accidental pollution at a private facility unsuitable or damaged tanks or reservoirs
Microorganisms
Rainwater, cisterns, or unprotected wells can develop algae or microorganisms that cause visible discoloration.
Possible colors
- Green
- Dark brown
- Cloudy yellowish
Is it dangerous?
Yes. Analysis is recommended when the water is intended for consumption, as the presence of microorganisms may indicate contamination.
Common Causes
- water stagnation in unsecured reservoirs exposure to light, which promotes algae growth
- lack of disinfection
- intrusion of organic matter or bacteria
What should I do if my water is discolored?
When should you be concerned?
Can colored water be filtered?
Yes, and it is even recommended when you want to ensure the potability of water from wells, rainwater, or an unreliable water supply.
The role of ORISA filtration:
- eliminate bacteria, viruses, and protozoa
- retain suspended particles reduce turbidity
Keep in mind: water containing tannins may remain slightly colored even after filtration. This slight color does not affect the sanitary quality, as tannins are dissolved molecules that are harmless to health.
How does the purifier work?
Equipped with an ultrafiltration membrane, it can treat up to 20,000 liters of water by simple manual pumping. Initially designed for humanitarian emergencies, ORISA® is now used by many households.
In summary:
