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What is the best way to raise PH level of water?


I am helping to design and implement a large water distribution system with about 3000 beneficiaries. The water sources that we will use have been tested and failed on account of a low pH level. I was wondering if you could help me find a good way to raise the pH level of the water for this rural community. The system will incorporate a slow sand filter to ensure good water quality into the future.


Binaya, it would be useful to understand how low the pH is and why. Low pH (acidic) water, depending on how low it is, has the potential for a range of dissolution reactions to occur along the pathway of the water source – irrespective of what that source is. For example, if you were using a groundwater source impacted by acid mine drainage, you would most likely need to deal with more than just the pH problem (such as a whole pile of metal compounds that would be present in the acidic water). Could you give some more information on the situation? Many thanks, RedR TSS

RedR TSS gravatar imageRedR TSS ( 2013-11-01 09:54:55 )

Hello @Binaya many thanks for your enquiry. To add more information as suggested by @RedR TSS, please simply click edit or to update your question.

KnowledgePointAdmin gravatar imageKnowledgePointAdmin ( 2013-11-01 12:40:51 )

1 Answer


Binaya, Fundamentally you will need to increase the water pH by applying either ground limestone (calcium carbonate) or soda ash (sodium carbonate) depending on what is more readily available to your community. If you use limestone you will need also to consider the impact this has on water hardness. Likewise if you are using soda ash then you may have to consider the salt content of the water and it's health implications if you are requiring high doses to have sufficient impact on the pH. The UK guideline for Na is 200mgNa/l at the tap but this may vary in the country in which you are based. I hope this is of help. If you can provide more information on this project including location, water source, cause of low pH (if known) and the need for disinfection. we may be able to give more specific guidance. Kind regards Harriette