Serving parts of North West London and the Home Counties.

Water Chlorine changes in Tendring


Chlorine has been used as a disinfectant in drinking water for over 100 years and at the levels added it is not harmful to health. These levels are routinely monitored at our treatment works, during distribution and at customer's properties.

During February 2018 we increased the levels of Chlorine in the water we supply to Tendring. This is to ensure the water we provide remains of a high standard and to bring it in line with our other supply areas.


Is the water safe?

Your water supply is safe. Monitoring at our treatment works and the water throughout the area confirms the drinking water meets strict requirements set out in the Water Supply (Water Quality) Regulations 2016. The increase in chlorine has been done to ensure the water remains at this high standard.


What are the current levels of chlorine?

We have taken water samples that confirm the levels of chlorine in the area range from 0.05mg/l to a maximum of 0.23mg/l, (milligrams per litre is the same as parts per million, so 0.05mg/l is 0.05 parts per million).

This is still significantly below the typical chlorine concentrations in drinking water and is below what normally can be detected by consumers.


What does The World Health Organization (WHO) say about chlorine?

"Chlorine is produced in large amounts and widely used both industrially and domestically as an important disinfectant and bleach. In particular, it is widely used in the disinfection of swimming pools and is the most commonly used disinfectant and oxidant in drinking-water treatment.

Present in most disinfected drinking-water at concentrations of 0.2 – 1 mg/l

The World Health Organization guideline value 5 mg/l (5000 μg/l)"

(Source: World Health Organisation : Water Sanitation Health Publications p334)


 World Health Organization Chlorine Infographic


Taste of the water

The chlorine in your water is at levels that would not normally be detected. Therefore, it is likely any difference in taste is due to chlorine reacting with internal plumbing fittings producing “TCP” like tastes.

Further advice on how to solve this issue can be found here>>:

For further advice about antiseptic/ TCP taste in the water click here >>



My eczema has got worse, is it related to the chlorine change?

No. chlorine in your drinking water will not cause or exacerbate eczema. If you are concerned about a skin irritation you should seek advice from your GP. We are unable to offer medical advice. This is consistent with advice from the National Eczema Society and Public Health England.



Are there any other health effects relating to this change in chlorine?

Sickness, nausea, headaches, sore throats are not related to the change in chlorine. There is no association between chlorine in drinking water and any adverse health impact.



Why do chlorine levels differ in some areas?

Levels of chlorine will vary slightly depending on how each area is supplied, temperature, demand etc. Areas supplied from reservoirs or that are further away from the treatment works may get slightly less chlorine than those areas fed directly from treatment works due to the water’s natural demand for chlorine and chlorine dispersing over time. Chlorine levels will never exceed the original dose which is strictly controlled and monitored with on-line equipment and verified manually.



Are there any further plans to adjust the levels of chlorine up or down?

There are no plans to make any further adjustments to the level of chlorine. Results indicate that we are just achieving the required level in the reservoirs and distribution system. We hope to be able to resolve consumer’s individual issues without compromising the water quality supplied to the area.



Why were consumers not pre-warned of the change?

Affinity Water decided against pre-warning consumers of this change as we did not believe this small rise in chlorine would impact consumers significantly. Chlorine levels remain very low and there have been no other changes.