Removing Nitrates From Your Water Supply
Nitrates are commonly found in UK water, particularly in private water supplies (wells, boreholes etc).
Their presence is often the result of over-fertilisation by farmers but can also be caused naturally eg by rotting vegetation.
Nitrates are particularly prevalent in agricultural areas ie where fields have been sprayed. The rain washes the fertilser off the fields into aquifers which eventually end up in the water supply.
The limit for nitrates in drinking water is 50mg/L (WHO / EU and UK's Drinking Water Inspectorate).
How to Remove Nitrates
This depends on whether you want to remove it from your drinking water only or from the supply to your whole property:
(More details on each below)
Adverse Health Effects.
Standard / allopathic medicine concerns focus on Methemoglobinemia aka Blue baby syndrome. This is very rare - the last case in the UK was in the 1950s - but it can be fatal. It is certainly a risk with untreated water.
Alternative health concerns: very few it seems.
If you are on normal mains water you are unlikely to need to worry too much about nitrates unless you have a particular issue with it - in which case see just below for solutions to remove it from your drinking water.
A) Nitrate Removal From Your Drinking Water
Unfortunately you can't simply boil water to remove nitrates. Like many chemical pollutants, boiling it will have no effect. (In fact the nitrates might simply increase in concentration because the water evaporates leaving a higher proportion of nitrates to water).
Nitrates can be filtered out from your drinking water by the following methods:
- Distillation (thorough but fairly long-winded and impractical)
- Ion exchange (aka various "Nitrate removal resins" in cartridges which are maintenance heavy and not thorough. Performance declines over time)
- Reverse osmosis
The latter ie a reverse osmosis water filter is our recommended solution for reducing nitrates in your drinking water supply.
Not only does RO remove a wide range of other contaminants from your water but it will maintain the same level of performance for the life of the filters.
This compares well with Ion exchange resin cartridges which, at the beginning, work at say 80% effectiveness during the first Month, and then decline to minus 60% in Month 3, and so on.
Reverse osmosis will typically remove between 50% to 90% of nitrates - the actual percentage will depend on what else is in your source water* but you can expect it to be at the highest end of that scale ie nearer to 90%.
*(For example sodium and / or sulfates, and a low water pH will all reduce the effectiveness of nitrate removal).
Read more about reverse osmosis for removing nitrates from drinking water - click here
B) Removing Nitrates from the Supply to Your Whole Property
Nitrates can be removed using a similar unit to a salt water softener, however instead of using softener resin, you would use nitrate removal resin.
This will need regenerating with salt.
The unit we offer is capable of a flow rate of 1.2m3/hr and has a capacity of 5.1m3 per regeneration.
Ongoing Costs for Salt Usage
The unit would work on a metered capacity rating so when it knows the media inside is expired, it would regenerate and make it reactive again to the incoming water.
Each regeneration would use 3.2kgs of salt.
So on average this unit would use around 3.2kgs of salt every 2-4 weeks to remove the nitrates. (A cost of about £2 per week - much cheaper if you buy the salt in bulk).
Ongoing Costs for Nitrate Removal Media
Every 5 years or so the nitrate removal media itself would need replacing (Cost for this size unit would be about £597 at current rates).
Full prices and details of the whole property nitrate removal filter.
What Percentage of the Nitrates are Removed by the Whole House filter?
Nitrate resin when working correctly, and with the correct contact time (ie not exceeding the max flow rate) , will usually remove 90% of the nitrates.
Where to Install it
Typically a nitrate removal filter for the whole house would be installed before the water tank. (Almost any property accepting a private water supply will have a holding tank).
This is because the flow rate into a tank is much more constant - and slower - than on the outlet side, where the outflow will depend on how much water the property happens to be drawing from the tank.
The private water supply should almost certainly have an Ultraviolet filter aswell. (The UV would always go after the tank).
Electrical Power
These units operate with a standard 3 pin plug 240V
Customised Quotes
If you need a nitrate removal filter for your whole property please contact us to discuss your needs by email or phone and we'll be happy to give you a free customised quote.
Image: A typical large nitrate removal filter
