Tuesday, March 21, 2017

Before you rush out to install a filter to improve water quality, think about this...

I just went for eWASH (emergency water, sanitation and hygiene) training conducted by Singapore Red Cross over the weekend. Designed for responding to emergencies and disaster scenarios, it definitely provides a fresh angle on the old topics of water and sanitation. By the way, to me, water and sanitation are simply 2 sides of the same coin (see earlier post on why people learn about wastewater). You can't work on one (usually water) while ignoring the other (usually wastewater) because wastewater typically has a habit of getting back at you through your water if you neglect it.

But hey, when you progress to WASH (water, sanitation and hygiene), you now have a whole lot more factors to consider in addition to getting safe drinking water. (Admittedly, WASH is commonly associated with developing communities but we in developed countries can certainly learn a few things too.)
  1. Do you wash your hands before eating and after visiting the toilet?
  2. Do you in fact use or have a toilet?
  3. Is the way you store your water free from contamination?
  4. Is your garbage and other solid waste properly disposed?
  5. Is your food safely prepared, handled and served?
  6. Do you know that children excreta is just as hazardous as adults'?
Often times in disasters or developmental work (including our students' overseas community service trips), we are too fixated on providing safe, clean drinking water to our beneficiaries. So much so that we forget about the other aspects of health e.g. sanitation, hygiene. In some situations, tackling those less sexy topics can bring about better results to our beneficiaries.

In any case, before we jump in to install a low-tech rainwater harvesting system or a high-tech reverse osmosis water production unit, perform a needs analysis first, whether in a disaster or development scenario. Work on those needs at the top of the list first and not what we "feel" or "want" to do.

My training session provided an interesting study (can't remember the source to cite though) to help bring things into perspective.

Based on various cases, it ranked the effectiveness of the following 4 methods to decrease morbidity rates of diarrhea. Most effective is ranked first... down to the least effective at the bottom. Guess what is at the top and what is at the bottom???

Figure: Do not underestimate the power of the humble washing of our hands

  1. Hand washing ~30+%
  2. Latrine usage ~30+%
  3. Sufficient water quantity ~15+%
  4. Water quality ~15+%
So you have it... water quality is important but check that you have covered more critical gaps before jumping straight to improve upon it.

Updated by author 23/3/17:
Dr Yoke of WISE (WASH in Southeast Asia) has kindly recommended the following articles on the above topic.
  1. Esrey, S.A. et al. Effects of improved water supply and sanitation on ascariasis, diarrhoea, dracunculiasis, hookworm infection, schistosomiasis and trachoma. Bulletin of the World Health Organization, 69 (5): 609-621 (1991)
  2. Fewtrell, L. et al. Water, sanitation and hygience interventions to reduce diarrhoea in less developed countries: a systematic review and metal-analysis. Lancet Infect Dis 2005; 5: 42–52
If you read through them, there exists some uncertainty associated with the data and conclusions. Nevertheless, the idea remains the same - a health programme (even a personal one) should not be overly focused on one particular aspect, say water quality. A holistic approach is ideal but in a non-ideal world in which resources are limited, we should still open our minds to other factors, perform a realistic needs analysis and work on the most critical factor and not on the factor we have a preference to.

Tuesday, March 07, 2017

3 Critical Questions to Choosing Your Water Filter

With the recent announcement of a hike in the price of water in Singapore by 30% (implemented over 2 years - 2017 and 2018), there is a need more than ever to conserve water (and money).

For those who are thinking of getting a water filter, you should be doing so based on cold rationality and not paranoia or hearsay. To help you with this task, do read on about what I have to offer.

I have always thought of writing a book on how to properly choose a water filter. What factors to consider? What kind of homework one should do beforehand?

As always, time is always short in supply but high in demand so that project has been put on hold. And frankly, I do not know whether there is actually a market demand for such a book. Dear reader, your comments are welcome in this matter so drop me a message/email/comment on whether you feel there is a need for such a product or if it is a silly idea.

Nevertheless, I still feel that my posts on water filters and water testing are not as coherent as I wish so I went ahead to summarise and organise them into a coherent decision process flow. The end result is a document which I hope you will find useful.

At its core, this is a process I have developed over the years to enable you to choose your water filter as painlessly as possible while still covering all the critical bases in your decision making

Note that this document only deals with removing pollutants from your water. It does not address adding "beneficial" supplements e.g. magnesium, alkaline water, hydrogen water into your drink.

Click here to access the document FREE. (You will have to opt in first.)


Friday, February 24, 2017

Learning journey to Choa Chu Kang (CCK) Waterworks (WW)

As part of my workshop on Anatomy of a Water Treatment Plant for Professionals, we visited CCK WW. It was real eye opener for me and the participants. Though I have visited Chestnut Drive WW previously, there are enough differences (now and then, Chestnut Drive vs. CCK) to make this trip a genuine learning journey.

Regrettably, one major difference is the prohibition of photography in the plant so I have no images to display here.

Without giving away too much (you have to go there to see for yourself!), here are some interesting stuff from the trip.
  1. Kudos to the PUB staff there! They are visibly passionate about their work and were patient in answering our questions throughout the trip. At one point, we were stuck at a certain place because of rain. Our guide called for help in the form of plant truck to ferry the lot of us back to the admin building. Nice...
  2. Lots of upgrading works in the pipeline
    1. Polymeric membranes will give way to ceramic membranes which are supposedly tougher and longer lasting.
    2. Biological activated carbon (BAC) will be used soon to polish up the treatment
  3. Remote monitoring is the trend! Online monitoring of various parameters is done pervasively throughout the plant. And that is not all... the parameters can be monitored all the way at PUB HQ. Anything goes off specs, CCK will receive a questioning call. The monitoring system also ties into sms messages that inform the staff when things go off specs.
  4. Backup is the norm
    1. Generators are always on standby in case the power goes down.
    2. SG actually has a standby waterworks. I won't tell you which one here.
    3. We have a standby reservoir too! It is not actually used in day to day operations!