Tuesday, November 22, 2011

Day 173: So Just How Good Are Biosand Filters?

Something happened recently in regards to the biosand filter program that just made me smile and reinvigorated me - we finally got our water testing kit up and running, and could begin to get some results on exactly how well our filters peform. Thought I'd share.

Before I post the photos, you need a bit of water testing knowledge to understand what you're looking at, so take out your notebooks people, it's time to get schooled. (If any of you happen to be microbiologists, and I messed any of this up, by all means I invite you to mock my incompetency in the comments.)

When you test for biological contamination in water, there are different tests you can do, one of the most common being testing for thermotolerant fecal coliform, a type of bacteria that is found in feces. That's what our testing kit is designed to test for. If you find that in water, it's pretty safe to say other nasty stuff is in the water too, things like vibrio cholera, the bacteria that causes (can you guess?) cholera, which is something every Haitian is all too aware of and rightly concerned about. Thermotolerant fecal coliform is measured in how many colonies they form per 100 ml. of water tested. Basically, you gather your sample water and then put 100 ml. of it through a small filter paper that will trap any bacteria present on it. Then, you put that filter on a pad full of food that thermotolerant fecal coliform like and put the petri dishes with the filters and pads in the incubator and to let them cook at just the right temperature for the fecal coliform to grow. The next day, you pull the petri dishes out, open them up, and count how many fecal coliform colonies you have on the filter paper to get your results, which are again measured in total colonies per 100 ml. of water tested. In the US and other First World countries, the acceptable level is zero. None. In the developing world, there doesn't seem to be a set standard, so opinions vary but a lot of organizations say less than ten is low risk. Anything over ten is not good. Fecal coliform colonies appear as little yellow dots on the filter paper you grow them on during testing.

OK, so now you know the basics of the technical stuff. Onto the other side of testing - what we test. In terms of our program, we test three things: the source water (the beneficiary's pump, well, river, etc. - whatever they get their drinking water from), we test the water coming directly from their filter, and we test the water in the container they use to store their water. We test the filter water twice to make sure we get accurate results. What kind of results? These kind of results:

The results from testing 100 ml. of water from the river in Barriere Jeudy, our first beneficiary community. This is very, very dangerous water. It is impossible to count the amount of fecal coliform colonies present. (You can see the individual colonies around the edge of the filter paper.) A lot of people drink this water.
Another view of the 100 ml. sample taken from the Barriere Jeudi river, this one without the camera's flash.
When you have so many fecal coliform colonies that it becomes impossible to count them, you can try and make it more manageable by testing less water, counting the coliforms, and then multiplying the result by the amount that you lessened the water tested. In this test, we ran 10 ml. of river water through the test instead of 100 ml. It is still incredibly contaminated, maybe between 300 - 500 colonies, so I'd guesstimate the river water has somewhere between 3000 and 5000 fecal coliform colonies per 100 ml. of water (300 to 500 x 10 since we only used 10 ml. of water for this sample). Again, the acceptable level in the First World is 0. In the developing world, roughly 10 or less. More than that is dangerous. However, when the river water is run through the biosand filter...
...zero. I don't count a single fecal coliform colony on this filter paper. Zero. Totally safe to drink. Amazing. And just to make sure...
...we tested the filter water twice using two samples. Same result. However, perhaps the most interesting test is...
...this one. The water used for this test came from the storage container the  family uses, and  highlights why education is the most important part of the biosand filter program. Clearly, this water is contaminated. It isn't nearly as contaminated as the river water, but it has fecal coliform present (the yellow stuff, the other colors don't matter). This is unsafe to drink, which is frustrating because, as we've seen, the water coming directly from the filter is totally safe to drink. For whatever reason (either our failure to teach them correctly, or their decision not to heed our advice) this family is not properly collecting and storing the water their filter produces, putting them at danger for waterborne illnesses. They were not using the container we give to all of our beneficiaries, which is one of the best receptacles to use with a biosand filter, and instead were using an open bucket. Unfortunately, most of our recipients are poor, and the bottles we provide are worth over $5US, so I expect they sold it, even though it is written into our beneficiary MOU that they can't do that. Clearly, open buckets are not a safe water storage solution. 
So there you have it, a quick run through some initial testing results we've seen. To be clear, this doesn't mean every filter will perform like this, and to do any sort of serious testing, we need to collect far more samples before we can draw conclusions (which we are going to do) but this initial finding is both promising, and eye-opening, both because it shows how effective biosand filters are if used correctly, but also how education and proper water hygiene practices are just as important as having a working filter. The family whose tests results I just highlighted are still drinking dirty water because they don't know (or maybe don't care, but I don't believe that) how to properly store their water once it has been filtered. The next time I head to Barriere Jeudi I will be bringing my laptop to show the family these pictures. People are visual learners. Seeing this, as opposed to me telling them, could make all the difference. When I showed this to the BSF team today during a training session, you could see they understood it in a way I couldn't have made clear without the photos to back me, and that is exactly what needs to happen for our beneficiary families as well.

As always, life in Haiti proves to be unpredictable - some days are amazing, others not so much.

Today was a good day.

Day 173: All Hands Holiday Appeal

Looking to do something different this holiday season? Sure, gift-giving is fun, but I encourage you all to support an organization that is making real, lasting change:


You can support All Hands here. Thanks.

Friday, November 18, 2011

Day 169: Photos

It has been a while since I've posted any photos, and unfortunately it looks like my little handheld video camera is lost and/or stolen so videos may not be as often. Still, I've had a couple of fun trips recently, thought I'd share:

Days of the Dead [Nov. 1st & 2nd, Gonaives, Haiti]

Sunday Coffee @ Hotel Oloffson [Nov. 6th, Port-au-Prince, Haiti]