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What is the best water testing system for rural Uganda to check if the water is safe to drink?

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This all depends on the type of water source - protected borehole, open well, rainwater harvesting, river or lake, etc. And the level of treatment it therefore requires.

The biggest issue in terms of water safety is likely to be biological contamination - bacteria, viruses and other microbes of faecal origin. Unfortunately biological testing is not particularly easy - delagua (http://www.delagua.org/) produce very well respected kits that do things the traditional way using appropriate technology for rural development and humanitarian use, however they are relatively expensive in terms of initial outlay.

There are also numerous test kits that will indicate presence or absence of one or more microbes, however some of these are two specific and won't catch everything & others may work out too expensive for regular testing.

In general you need to look at the source to determine the likely risks. If you are using surface water I would recommend disinfection with some form of chlorine. If you do this you can also monitor the chlorine concentration relatively easily (or even smell it) generally speaking if you still have chlorine present in a low turbidity water (less than 2 NTU) after 20 minutes of contact time then the chances are that you won't have an issue with bacteria or viruses.

Then there are many other potential chemicals (metals, pesticides, etc.) that may be in the water. I would recommend that you initially take samples for lab analysis in the nearest large city. From the results of these you should find out what you need to monitor more closely locally & specific kits could be recommended for these.

There are some things that are relatively quick and easy to measure that will give you a rough idea of whether your water quality is changing with time. Measures like turbidity, conductivity, pH.

I'd suggest you have a look at the answers to this question too - as it is quite similar & a number of kits & resources are recommended: http://knowledgepoint.org/questions/681/availability-of-cheap-and-simple-water-testing-kits/

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There are Hydrogen Sulphide kits H2S which show the presence or absence of faecal coliforms (there is some debate about them). They are available here: http://www.lteksystems.com/bactoh2s/h2sstripkit.htm

Here are publications that might help:

-The Oxfam manual on emergency water quality testing is good

-the WHO guidelines on drinking water quality are definitive (found at http://www.who.int/water_sanitation_health/norms/en/index.html)

You probably will have to carry out a strong level of hygiene promotion to make communities understand about water quality and disease and to try to change their behaviour. The PHAST methodology http://www.who.int/water_sanitation_health/hygiene/envsan/phast/en/ (Participatory Hygiene and Sanitation transformation) is good but not as the name suggests.

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A recent development currently undergoing field trials is a low cost single test unit for faecal coliforms / e.coli. The University of Bristol, heavily funded by the Gates Foundation, have developed the unit; it is said to be very low cost and simple to operate and to dispose of. It is intended to simplify field testing, see:

http://www.bristol.ac.uk/engineering/...

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To look at the reasons behind the question, testing by itself will not tell you much. A much cheaper, flexible and appropriate method - promoted by the World Heath Authority is to do a sanitary survey

http://www.who.int/water_sanitation_h...

This will allow you to work out the risk of faecal pollution. Also talk to your District Water Officer! It's their job

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There is a company in Kampala called Jabba Engineering that represents Palintest - a UK based organisation that manufacturers a wide range of water quality monitoring products ('Palin' is from Dr. Palin, who invented the DPD method of measuring chlorine in water). They supply Wagtech kits (similar to Delagua kits), presence/absence media, and a full range of other water testing instruments. What's been good with Palintest products in Uganda (mostly their wagtech kits) is that they are supplied in custom designed cases with ranges of instruments in to suit particular requirements i.e. chlorinated piped source, groundwater monitoring etc. Jabba Engineering have been providing training courses accredited by Palintest to Government and NGOs across Uganda. Contact: jabbaengineering@yahoo.com

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Hi,

I thought I'd share this post just in case of interest or relevance - perhaps something you've already heard about: http://www.bath.ac.uk/research/news/2014/08/11/electric-bugs-water-sensor/

Scientists from our Department of Chemical Engineering have developed a low-cost device that could be used in developing countries to monitor the quality of drinking water in real time without costly lab equipment.

Current methods of detecting pollutants in water are costly, time-consuming and require specialist technical expertise. However researchers from the University in collaboration with Bristol Robotics Laboratory at the University of the West of England, have created a low cost sensor using 3D printing technology that can be used directly in rivers and lakes for continuous water quality monitoring.


If of interest might be worth following up with them to find out more.

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I just came across your question and would like to suggest our company's water quality test, the Aquagenx Compartment Bag Test (CBT). The CBT is a simple, portable test for E. coli bacteria that determines the health risk of water. It is ideal for on-site water quality testing in rural, low resource and disaster/emergency settings. The CBT generates quantified, color-change test results without the need for labs, electricity or expensive, extra equipment. It also enables ambient temperature incubation at 25 degrees Celsius and above, works at variable temperatures and does not require constant temperature control in an incubator during the incubation period.

The CBT's simplicity and convenience remove the barriers to bacteriological water quality monitoring where testing was previously too difficult, impractical and costly. It is used a great deal in African countries and around the world.

I'd love to give you more information on the CBT! Please contact me: Lisa Hirsh, Aquagenx, lhirsh@aquagenx.com, www.aquagenx.com

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There has been an extensive discussion on the pros and cons of different kinds of rural water quality monitoring options on the Accord Network Linkedin discussion group (free registration required):

https://www.linkedin.com/groups/Water-Quality-Testing-in-Field-4225693.S.5823858511158726658?qid=16d6e013-42f8-4916-9c84-72d61b74afbb&trk=groups_items_see_more-0-b-ttl

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The key thing is to prioritise which aspects of water quality you believe to be most important (i.e. the most likely threats to health). As others have pointed out, this depends on the water source, but also on the geographical and geological location and consequent local influences on water quality. Usually for rural supplies bacteriological quality is the most critical, and you have plenty of leads on that in previous posts. But also, if using groundwater, check an "oldie but goodie" at https://www.bgs.ac.uk/downloads/brows... (or search "bgs wateraid groundwater quality Uganda"). This general summary points to potential chemical threats in particular locations.

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Uganda has it’s own water quality standards, which can be reviewed at https://law.resource.org/pub/ug/ibr/u... . How relevant the parameters are to health is debatable if compared against the WHO Standards for Drinking water quality, but as they are the legal standards in the country any debate here is moot. I would recommend choosing kit that can measure the chemical parameters in the referenced standard. Obviously you need to ensure when choosing kits the minimum detection limits published by suppliers meets the standards requirement. Wagtech produce a good range of colorimetry based field kits, which are quite cheap. They aslo have an agent in Kampala, check on their website: http://www.wagtechprojects.com/

In addition the pallintest 7100 photomeeter is an excellent and versatile bit of kit. Unfortunately the unit itself costs around UK 1500. From the generality of the question I am guessing the you do not have the commitment to water quality testing to justify the capital costs to justify the initial capital outlay. If I am wrong then the costs of reagents are quite reasonable, the costs per test work out between 72 pence and £2.20, depending on the parameter. All of the chemical parameters in the standard can be reliably tested remotely from samples without specific preservation steps. The bulleted list below specifies the exceptions and the equipment that you would need to include in a field kit:

  • Electrical conductivity: simple handheld digital meter;
  • pH: Recommend a simple hand held conductivity meter, but you can use colorimeter kits;
  • Coliforms - The Ugandan standards do not specify a numeric limit for coliforms, so simple presence absence tests are likely to be sufficient for your purposes. You could check out the Colliert products. https://www.idexx.com/water/products/.... An alternative is the Wagtech Potatest kit. This is quite challenging to use, and requires a fairly significant investment in infrastructure and tertiary equipment (refrigerators, autoclaves, and some seriously hard to come by chemicals). Having used this kit extensively in the past (and the similar Delagua kit from Oxfam) I have found them quite hit and miss. This is not a reflection on the quality of the equipment, more the difficulty in maintaining sterile conditions under field conditions).

To echo the contributions of other posters, in terms of assessing water quality and risks to human health, sanitary surveys are of more practical importance than sophisticated testing. This is recognised in the latest WHO guidelines. Check out the following for a description. http://www.lboro.ac.uk/well/resources...

Uganda does have a reasonably good commercial lab in Kampala and water quality parameters can be tested through the government lab and I believe through one of the universities. You should check out these options as they are probably the most cost effective for non-routine testing for chemical parameters in the long run.

Hope this helps, and good luck

John Cody

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