low-cost ways to treat water
March 11, 2012

Ten Low-Cost Ways to Treat Water

Having money helps, but clean water solutions for low- and middle-income countries don’t have to be expensive. Celebrities like Bill Gates, Matt Damon and, a celebrity to us, Susan Davis, to name a few, have helped clean rivers, dig wells and install pumps, pipes and other hardware to deliver clean water. Their time and money are well spent because the problem is huge. As we’ve reported before, as many as 1.8 million people die each year from diarrhea linked to bad water and sanitation, most of them under age 5.

Community-wide water infrastructure is as good as it gets. But until everyone has it, there are other, cheaper clean water solutions for LMICs. Boiling water over a wood fire is one of the most widely used methods, but it is also a health hazard for those working in poorly ventilated kitchens, and it exacerbates deforestation. Instead, we’ve rounded up ten low-cost ways to treat water, and not one requires boiling. Do you know of other methods? Please let us know in a comment below.

Ceramic filters

ceramic Clay, sawdust and a plastic bucket can make a water filter that catches dirt and disease-causing microbes. In the classic design, mix clay with a combustible material like sawdust or rice husks, give it a flower pot shape and fire it in a kiln. The sawdust or rice husks burn away, leaving tiny pores in the ceramic through which water filters. Organizations around the world have been using this kind of ceramic filter to reduce disease in impoverished communities for years.


Bone char filtration

filtersNot all filters remove heavy metals or other toxins from the water, but crushed and charred animal bone can. In areas where toxins leach into the water, removing them is a good idea. Chronic arsenic exposure, for example, can cause skin cancer, bladder, kidney and lung cancers, gangrene and possibly diabetes, high blood pressure and reproductive disorders. Uranium in the drinking water is linked to nephritis (pdf)—inflammation of the kidneys. As they inflame, the kidneys dump proteins that the body needs into the urine stream, a condition that can be lethal.

When a US Geological Survey study found high levels of arsenic and uranium in wells in the Ogala Lakota tribe’s US reservation at Pine Ridge, students at the University of Illinois at Urbana-Champaign had an idea: bone char. Crushed and charred cattle bones are cheap and locally available. With the right design, filters like the bone-char prototype pictured can clean contaminated water right in the home. It’s a solution that can work in Pine Ridge or anywhere arsenic contamination is rampant. Clean water solutions for LMICs are not universal, however. In some regions, bone char may face cultural aversions to ingesting cow products.

Slow sand filtration

way to clean water Slow sand filtration has the advantage of working on an entire community’s water source, not just individual households. Practical Action put together a technical manual for slow sand filtration systems, a complete guide to their construction and maintenance. Follow the link above to see the manual.

A slow sand filtration system is a combination of several parts: water storage tanks, an aerator, pre-filters, slow sand filters, disinfection stages, and filtered water storage tanks. The number of filters and filter types that are used in a given slow sand filtration system will depend on the quality of the source water and will be different for each community.

Everything-but-the-sink portable filter

methods for cleaning water This portable filter design was proposed in response to a call for better water filtration solutions at taps in India. It uses chlorine, silver beads, activated charcoal and sand. Honeybee Network posed the original problem and an E4C member posted this solution. It includes a detailed guide to the specifications, materials and construction of a portable filter built from everything but the kitchen sink.

Honeybee Network also proposes phones as clean water solutions for LMICs. Mobile applications that employ a phone’s camera claim to sense impurities in water. We Googled up two that are in development: The H2O Mobile Water Testing Lab and Aquatest, though it’s not clear if the latter will be phone based or not.

Bamboo charcoal

way to clean water In this spin on the charcoal filter, a team of E4C members in Bangalore propose a filter made of locally available materials including charred bamboo, gravel and natural adsorbents. “The process we propose is indigenous, eco-friendly, low cost and entails minimum maintenance,” the team writes in their workspace. They estimate that their filter can handle 30 liters of water per hour, and it would be affordable for average households in the region.


Solar sterilization

Ways to Clean Water If cost is a bigger concern than time or convenience, the cheapest way to treat water is to leave it in a plastic bottle in the sunlight. Leave clear bottles in the sun for a few hours and UV radiation and heat kills the microbes that cause diarrhea and other waterborne illness. The Sodis (for solar disinfection) method was deployed in some parts of Haiti after the earthquake in 2010, and it is used in emergencies and impoverished regions worldwide.

If the bottle is too basic or prone to error, Solvatten sells a more highly designed solar disinfection device. It’s a jerry-can-like container with a built-in thermal indicator that lets drinkers know when the water is safe to drink. The Solvatten container opens like a book to expose the water inside to sunlight through clear plastic panels. Its black backing helps it absorb more sunlight.

The amount of sun exposure that a bottle needs varies by the amount of sunlight available (it takes longer to sterilize water on a cloudy day). To take the guess work out of the solar method, a disinfection indicator can measure light exposure and signal when the germs are dead. We came across this prototype of a solar indicator at IEEE’s Global Humanitarian Technology Conference in Seattle, Washington (USA). And there’s also Helioz, a similar concept with a top-mounted design.

Solar distillation

ways to clean water Not to be confused with solar sterilization or disinfection, solar distillation purifies even muddy, salty or otherwise undrinkable water through evaporation and condensation. The power of distillation to purify saltwater makes it unique among the treatment methods featured on this page.

A solar still can actually be a cheap and simple piece of shaped plastic or glass, or they can be more highly designed devices. To work, the still allows sunlight to shine through a clear panel onto the impure water. The water heats and evaporates, then condenses on the underside of the panel and runs off into a container of some kind. This simple process takes huge amounts of energy, which is why solar stills can make more sense than stills powered by other fuels. Our Solutions Library links to a technical brief and construction guide to several different still designs from Practical Action.

Bicycle filter

Bicycles in all their glorious versatility and simplicity have got to be one of our favorite devices, and we were pleased to find not just one, but two bicycle-powered water filters. Nippon Basic Co. invented Cyclo Clean, a bicycle rigged with a pump to draw water from a river or well and a robust, three-filter system to purify the water. The filters are designed to last without replacement for two years, and the tires are puncture-proof. It can filter three tons of water in 10 hours.

Then there’s the Aqueduct, which is like Cyclo’s whimsical little brother. It’s a tricycle with bubbly curves and a sky-blue paint job that pumps up to two gallons of water through a filter while the rider pedals. Cyclo handles much greater volumes of water, but Aqueduct’s one advantage is that it can do its job on the move.

Both of these designs are in our – ahem – fantastic list of ten things you can do with a bicycle.

Emergency homemade filter

water filtration The plastic bottle makes yet another appearance as a water treatment device, this time as a simple filter that can remove sediment and even disease-causing microbes. Simply cut the bottom from the bottle, fill it with layers of gravel, sand cloth and charcoal, filter the water through it and hope for the best.

This design is also featured in our list of the best appropriate technology DIY plans.



chlorinate water We saved the most reliable treatment method for last. Chlorine can work in the community water supply to kill microbes before it enters people’s jerry cans or home water supplies. And it keeps the water safe from new contaminations long after it is added.

We’ve seen several interesting chlorination methods at work in resource-poor regions. Compatible Technology International developed this tested and proven device that chlorinates water in gravity-fed systems that fill a community water cistern. And these four experimental designs have worked in field tests to dose water accurately after people fill their buckets at a community well, stream or other source. The chlorinator, shown here fully assembled and broken down, attaches to a loop in the water pipe that feeds into the community tank. Image courtesy of CTI.

Chlorine is one of the most versatile and effective clean water solutions in LMICs and everywhere else.

E4C’s Solutions Library

Please see E4C’s Solutions Library for more clean water solutions for LMICs. In our database, you can view standardized information about hundreds of products and compare similar technologies side by side. To start, see the selection of water technologies such as water disinfection devices, and membrane filtration systems.

Comments from the Community


  1. Aakash shrihsrimal says:


  2. Dr Sergey pugach, homeopath says:

    You did not tell how to treat chlorine water. Why???

  3. Rob Goodier says:

    Chlorine is considered a method of treating water! Our goal was to treat water by removing life-threatening pathogens. But chlorine can be a problem, too. The bad taste it leaves can deter people from using it. If you know of effective, low-cost ways to remove it please share.

  4. durgesh soni says:

    I want water filter plant pls give me details

  5. Putu bagus sahadewa says:

    i sometime think in Indonesia whereas agro is essential but recently no many engineer involve in water treatment for low cost farm. to increase yield in farming one essential is to get better water because many river now are containing some effluent from factories around them and finally teh water consume also for human, farm etc.
    i need to discuss with some engineer overseas, how to get technologies go deeply in water treatment for farm especially for low cost farmer.

    my background education in chemical engineering and now working fro agrochemical business.

  6. Dan says:


    bUT i HAVE AN ISSUE i WONDER IF SOMEONE CAN CHIME IN ON. THAT WATER IN THE 100 GALLON STOCK TANK. i CAN’T IMAGINE IT CAN SIT LONG BEFORE GROWING SOMETHING. wITH THE CHLORINE FILTERED OUT. Is it possible to add chlorine directly to the water and then remove the chlorine when I am going to use it.

    PARDON the caps. It wouldn’t let me type in lowercase.

  7. sekani mkandawire says:

    I need to know the jobs to done on backwash and rinse methods

  8. anila tahir says:

    such a informative and b
    etter techniques u provided

  9. Shamshuddin Ahmad Mukhiya says:

    105/286 C,Sri nagar Opp Kesco & Police Station Chan Gunj Kanpur

  10. Ashley Turns says:

    Thank you for mentioning that just by using a bucket, clay, and sawdust, you can actually filter out dirt and other microbes. My husband and I have been wondering whether we should get our water treated and if so how. Though your ceramic filter can catch disease-causing microbes easily, we will probably be asking professional to treat our water so we don’t have any sort of harmful things in there.

  11. mugiri amando says:

    well, a lot has been done but more also should be done especially in developing countries where most people are poor and ignorant. am developing a solar water treatment system which could be affordadable to most ugandans who are facing a problem of waterborne diseases

  12. minon says:

    thank you so much.very useful information.

  13. Belinda Chung says:

    Really appreciated the low cost water filtration overview. I think this can become a passion of mine with certain addition I can see a business which has global applications.

  14. Trilok Jani says:

    Serve people’s is service of God

  15. Pat McCormick says:

    Why not a simple hyrdocyclone? Cyclones for removing dust from air are amazingly efficient, and I pelieve there is a way to simply swirl water to remove sand, grit, slurry, etc. There has to be a way to do this.

  16. Murari prasad Sharma says:

    Very nice information. Thanks

  17. student says:

    what is the most recommended filter?

  18. Dr khin maung aye says:

    Want to read more articles and if agree want to send an article about foot opeta

  19. Meareg desta says:

    Engineering for change!

  20. RAVI.Jadhav says:

    Every time &good to see you

  21. Dr Khin Maung aye says:

    Very useful intermediate technology for developing con

  22. Anonymous says:

    Good to all ideas low cost filter system are the solution to face the climate change.

  23. invwaterpbm says:

    1) What is involved ?
    The methods presented in this factsheet are used to make water drinkable. They can be applied at hole, at the family level.
    The methods described comprise :
    * Straining
    * The three pot method
    * Treatment by boiling
    * Treatment by chlorination
    * Treatment by ceramic filtersLifestraw method

    * Treatment by slow sand filtration
    * The Naiade method (UV radiation)
    * SODIS method (Sun radiation)
    * Solvatten method (Sun radiation)
    * Lifestraw method

    2) Why ?
    Treating drinking water prior to consumption combats many illnesses such as dysentery, typhoid fever and cholera.

    Illustration Red Cross
    3) Straining water through cloth
    It is easy to filter water using cloth. This kind of filtration will eliminate the main solid impurities from water as well as any insect larvae that it may contain. The cloth used, cotton preferably, must be thick enough to properly retain the impurities. If it is too thick, then filtration will take longer. It must always be washed prior to use.
    Straining alone is not a sufficient form of treatment. Nevertheless, straining water before treating it using one of the other methods described in this factsheet will significantly improve the quality of the water obtained.

    a) Advantages
    – Simple to use
    – Almost no cost
    – Very useful, or even essential for pre-treatment purposes

    b) Drawbacks
    – A summary treatment that cannot make water drinkable if already contaminated
    – Cost may be high depending on the energy source used

    4) The three pot method
    This method serves the same purpose as filtration by removing the main solid impurities found in water.
    For improved efficiency, this method may be used to complement filtration.

    Source : Household water treatment and safe storage in emergencies, International Red Cross Agrandir
    a) Advantages
    – Easy to use. Almost no cost.
    – Significantly reduces impurities and pathogens

    b) Drawbacks
    – Disinfection is not complete
    – Wait time

    5) Treatment by boiling
    Boiling too is relatively easy to do. It will kill all of the germs and micro-organisms present in the water. To do so, first filter or decant the water, then bring it to a rolling, bubbling boil (simply steaming water is not boiled) for one minute at low altitude and for at least three minutes at altitudes above 2,000 metres. Boiled water may lack taste. This problem can be solved by vigorously shaking the water purified to re-oxygenise it or by adding a little salt.

    a) Advantages
    – Easy to use
    – Kills all pathogens

    b) Drawbacks
    – Required wood (approx. 1 kg per litre of water) and a heat resistant recipient
    – Actual cost is relatively high

    6) Treatment by chloration
    (For more information, refer to Factsheet E 18 “Treatment by Chlorination”.)
    Chlorination is a simple and effective way to disinfect water to make it drinkable. It comprises introducing chlorinated products (chlorine tabs, bleach, etc.) into the water to kill the micro-organisms contained in it. After the products have acted for 30 minutes, the water will be drinkable. It remains so for a few days (depending on storage conditions) thanks to the non volatility of the chlorine.

    a) Advantages
    – Muddy water can be made drinkable. If the treatment is done properly, all of the pathogens are eliminated.
    – Chlorination has a durable effect.

    b) Drawbacks
    – Products must, for the most part, be brought in from elsewhere. Handling risks involved.
    – Non negligible cost.
    Chlorination may, for example, take place after flocculation, where necessary in an earthenware pot fitted with a tap on the bottom (The drinking water station dreamt up by Dr Monjour, see end) or in any other recipient.

  24. r.b.s.jonker says:

    Good article, have you ever looked at the ‘Watercone’ and if yes, what is the opinion about this technology? Why is it not broadly in use because it looks very promising invention.

  25. Rob Goodier says:

    That looks interesting, thanks for mentioning it. I’ve forwarded your comments on to the Solutions Library manager for possible inclusion.

  26. lagaka2282 says:

    I rather say that you have done remarkable research but some aspect of the diagram of water treatment needs some tweaking for getting more efficiency

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