Three Day Weekend
Saturday was the start of a three day weekend over what we call Halloween and in Guatemala is All Saints Day on October 31st and Day of the Dead or Dia De Los Muertos on November 1st. It's actually a national holiday, somewhat like our Memorial Day. Families go to the cemetery on that day and decorate the graves of their relatives, similar to Mexico. It's much more festive than in the US with the people having picnics and visiting, and children fly kites from the high points.
On Saturday morning, Susan and I went to visit a coffee plantation within the city limits of Coban. which had been founded by a German family. Apparently many Germans settled here in the beginning of the 20th century, going into coffee farming and cattle ranching. During WWII many were Nazi sympathizers and the US government pressured the Guatemalan government to kick them out. This one lasted however and was very interesting to visit. It was sort of old fashioned in some ways with old buildings and creaky machinery, but produced very high quality specialty coffee which they ship world wide. They also raise cardamom, a favorite spice of Susan.
Another interesting thing we learned was that the fruit of the coffee tree is sweet, sort of like a cherry, it's the seed inside the fruit that they dry and roast. They grew other spices there too like allspice and another one that smells exactly like Old Spice deodorant. It was pleasant to walk through their fields and smell the different spices and talk about all the different varieties of coffee beans.
Stan Withee was back at the hotel working on his report so we went back there and he wanted to go to the local Mayan museum, which was also close. It's a small private museum with a variety of materials from throughout the Mayan region, including locally. They had a lot of pottery and small figures. We found out that the Mayans made intricate molds for their figures rather than carving them, and they had a number of the clay molds there. There were two identical figures which showed that they had come from the same mold. The museum had used some of the original Mayan molds to make some figures of kings with feathered head dresses which they had for sale for several hundred dollars. I thought they were really cool, but there was no way they would make it home safely in one piece as we have three more weeks of traveling.
Amalia, our coordinator from Food for Hungry, wanted to go home and visit her family for the weekend so we were on our own for meals and entertainment. Cobán is a small city with not a lot of places to visit or eat. It's safe enough and the people are very friendly but not much to do. The streets are rough and narrow and full of fast cars and buses. It's frightening to walk along there sometimes with cars and trucks whizzing past inches away, but everyone seems used to it. We walked to dinner at a nice restaurant that has a lot of exotic native orchids on display, and on our way home we were caught in another torrential downpour and got totally soaked as if we had fallen in a lake.
On Sunday morning we wanted to have an adventure and see something different so we decided to take a bus out to see one of the nature preserves in the area, called a biotope. This region is known for its rain forests and some have been preserved and developed for people to experience. There is quite a bit of deforestation going on here so it's important to preserve what they can. They are also trying to save forest corridors for animal migration and breeding.
Minibuses that leave every few minutes in all directions and are very inexpensive, but they pack in as many people as can fit, then stop and pick up more along the road. We made the mistake of sitting next to the door where everyone squeezes in rather than in the back where it is less crowded, and so were pretty squished. Again Guatemalan people are very friendly and considerate of each other and always tried to make room or assist one another, so it wasn't too bad. Susan held one ladies packages, while I shared my two person seat with three other people.
It took about an hour to get to the biotope and they dropped us off at the side of the road. They have a little entrance area with some informational posters and displays, and there was a man with a few words of English there to explain them. We had a choice of two different paths, “senderos”, to take both making a look up through the forest. We weren't sure about the trails, so chose the lower, shorter one. It turned out that they were both fine, well maintained, but the shorter one satisfied us anyway. It didn't rain while we walked, even though clouds threatened and they normally get over 100 inches every year.
We saw a lot of interesting plants, including a wild orchid growing beside the trail which Susan photographed. The forest is so dense that it's difficult to see very far but we did hear some birds, and saw one that we think was a Toucan with a large yellow beak. There were giant tree sized ferns, and leaves of plants several feet across.
It only took us about an hour to make the loop, we could easily have taken the longer one, but that was enough to get a nice flavor of the biotope. At the end they had a little display of plants and animals in the park, sponsored by USAID. There were a couple of stuffed Quetzales birds, but apparently to see a real one is quite rare as they are endangered. They did have a lot of other plants and a few birds and animals as well.
We went back down by the road then and flagged down a passing minibus heading the other way back to Cobán. We were lucky this time because the bus wasn't full and we were able to get seats toward the rear away from the door and arrived home in about an hour. Because it was a holiday there were lots of people out doing things and it was interesting to watch them as we went through the little towns.
Monday was Dia De Los Muertos, November 1st, and on that day people go to the cemetery to remember their relatives who have died, or as they say “fallen” in Spanish. It's a nice family day and people bring flowers and candles to decorate the graves. Like in Southern Mexico they use orange marigold petals and pine needles around the graves, supposedly a tradition left over from the Mayans. The graves are mostly above ground in cement tombs that have been brightly painted with pastel colors. The cemetery is on a hillside overlooking town so it is very pleasant to walk around and talk to the families and look out. Another tradition is that the children fly kites on this day so there were several kids on the top of the hill trying to get their kites in the air. One family was having a barbeque and there is a little chapel on top of the hill with several food vendors there selling local dishes.
We were walking with Amalia our hostess/coordinator, and she was telling us about the various traditions. Most people believe that the dead persons soul leaves their body after death, but can also return if invited. There was a woman with an incense burner waving the smoke of pine resin or “copal” to call the spirits of the dead relatives. Copal has a very distinct smell and was considered a sacred smoke by the Mayas. Susan and I have some at home and sometimes burn a little at Christmas because it smells like pine.
Down at the bottom of the hill outside the gates of the cemetery there was a sort of street fair with carnival type games and vendors. People seemed to really enjoy the simple chance games they had. there. We walked down the hill from there and caught the local bus back to our hotel. It was a really nice holiday I'm glad we got a chance to enjoy it.
Saturday, November 6, 2010
Tuesday, November 2, 2010
Friday
Friday
On Friday of the workshop the plan was to set up the solar stoves the participants had made and cook a meal for everyone. One of the staff loves to cook and she was very excited about trying out both the solar and the rocket stoves. She was going to cook hard boiled eggs and beans and other things to demonstrate their versatility.
We woke up that morning to a torrential downpour. The streets were flooded and the wind was blowing. The climate here is very wet , it's cool and misty much of the year and the tops of the local mountains are usually in the clouds. That's why I wanted to demonstrate the rocket stove as an alternative cooking and water pasteurization method, but I wasn't counting on it being so dramatic a presentation. People here cook over open fires and I also was going to talk about a smokeless stove with a chimney, a cocina mejorada.
We got to the workshop and luckily were able to pull in under an awning to unload our stuff. It was raining so hard that we had to shout over the noise of the wind and rain on the roof, not a good sign for my talk. My original plan was to review the material from Thursday and then examine everyone's water tests. I had a few slides to show about that, then we were going to try out the stoves. It looked like I could set up the rocket stove under the eave of the building and try it without setting the place on fire so that part would still work and I then would have more time to talk about other things.
It's fun to look at the water samples with the participants, usually it's their own local water and so they are very interested in the results. Last year I was a little disorganized about the interpretation of results and people needed reassurance that they were interpreting their results correctly. This time I had everyone line up and one by one we looked at their slides and tubes. I asked each person to interpret their results and explain why they thought the samples were positive or negative, then we discussed them. It's difficult to correctly see the fluorescence of positive colilert tubes in bright light so we sort of crawled under a counter in a dark area to compare their tubes to positive and negative ones.
I was very pleased with how the class was able to correctly interpret their results, which meant that they had been listening yesterday and that they would be able to accurately test water themselves. After they had looked at their samples with me, I had them share their results with Susan and she made a table of results on the white board. About half of the samples were at least moderate disease risk, which is average for me in the testing I have done. Many of the people at the workshop drank bottled water, which is very expensive, but I emphasized how they could save money by just Pasteurizing local water. It also makes a better demonstration to others if you are drinking the same water you are advocating for someone else.
Then it was time for the rocket stove. I asked Stan to set it up for me under the eave and get it ready to light. Like most people he split up some wood which was way larger than necessary for the stove, tiny twigs and sticks work best at first to get the fire started. We lit it and after some huffing and puffing we got it going good. After a little while the flame gets so hot there is very little smoke and it shoots out the top of the stove. Sometimes the air intake makes a whistling sound, so it's interesting to see it work. The lady doing the cooking demonstration put on a pot with cold water and eggs to cook and the large pot began to boil within a few minutes. She also cooked a dish of refried beans and one other dish within a few minutes. One point of the rocket stove is that it cooks very quickly and is very hot and so the women are not exposed to smoke as much as in an open fire.
Everyone was very impressed with the stoves and asked a lot of questions about how to make them. There is some information available about them, but mostly in English. I'm going to try and write something in Spanish with some pictures and make it available to everyone. They are simple to build and not very expensive. I'm hoping someone in the community would be interested in making them and selling them locally which would be a good way to make them more available.
There is also a commercial model available called an “ecostove” that is made from cement. I just became aware of it the day of the workshop and wasn't able to find one to demonstrate, but I'll try to get the local staff of Food for the Hungry to buy one and see how it works. If they are not too expensive they may also be an alternative.
Things moved slowly here and it was then time for a break. I still wanted to talk about other topics like SODIS solar disinfection using UV rays, water filters and “cocinas mejoradas”, but time was running out. The hosts of the workshop scheduled some other activities and when I finally got to speak again I only had about a half hour to cover the rest of the material. I really galloped through it, and promised to send them some material later and then was done.
In summary, I think the workshop was a success. I put a lot of emphasis on accurate water testing and I think the participants understood that. I told them that the health and perhaps lives of people now depended on them to do their jobs well. I said that I was always available to help them and gave them all my email address, and I'll also write them with materials so we can keep in touch. I think follow up with them is very important as well and to encourage them to use the new knowledge they have.
Then I went back to the hotel and took a long nap!
On Friday of the workshop the plan was to set up the solar stoves the participants had made and cook a meal for everyone. One of the staff loves to cook and she was very excited about trying out both the solar and the rocket stoves. She was going to cook hard boiled eggs and beans and other things to demonstrate their versatility.
We woke up that morning to a torrential downpour. The streets were flooded and the wind was blowing. The climate here is very wet , it's cool and misty much of the year and the tops of the local mountains are usually in the clouds. That's why I wanted to demonstrate the rocket stove as an alternative cooking and water pasteurization method, but I wasn't counting on it being so dramatic a presentation. People here cook over open fires and I also was going to talk about a smokeless stove with a chimney, a cocina mejorada.
We got to the workshop and luckily were able to pull in under an awning to unload our stuff. It was raining so hard that we had to shout over the noise of the wind and rain on the roof, not a good sign for my talk. My original plan was to review the material from Thursday and then examine everyone's water tests. I had a few slides to show about that, then we were going to try out the stoves. It looked like I could set up the rocket stove under the eave of the building and try it without setting the place on fire so that part would still work and I then would have more time to talk about other things.
It's fun to look at the water samples with the participants, usually it's their own local water and so they are very interested in the results. Last year I was a little disorganized about the interpretation of results and people needed reassurance that they were interpreting their results correctly. This time I had everyone line up and one by one we looked at their slides and tubes. I asked each person to interpret their results and explain why they thought the samples were positive or negative, then we discussed them. It's difficult to correctly see the fluorescence of positive colilert tubes in bright light so we sort of crawled under a counter in a dark area to compare their tubes to positive and negative ones.
I was very pleased with how the class was able to correctly interpret their results, which meant that they had been listening yesterday and that they would be able to accurately test water themselves. After they had looked at their samples with me, I had them share their results with Susan and she made a table of results on the white board. About half of the samples were at least moderate disease risk, which is average for me in the testing I have done. Many of the people at the workshop drank bottled water, which is very expensive, but I emphasized how they could save money by just Pasteurizing local water. It also makes a better demonstration to others if you are drinking the same water you are advocating for someone else.
Then it was time for the rocket stove. I asked Stan to set it up for me under the eave and get it ready to light. Like most people he split up some wood which was way larger than necessary for the stove, tiny twigs and sticks work best at first to get the fire started. We lit it and after some huffing and puffing we got it going good. After a little while the flame gets so hot there is very little smoke and it shoots out the top of the stove. Sometimes the air intake makes a whistling sound, so it's interesting to see it work. The lady doing the cooking demonstration put on a pot with cold water and eggs to cook and the large pot began to boil within a few minutes. She also cooked a dish of refried beans and one other dish within a few minutes. One point of the rocket stove is that it cooks very quickly and is very hot and so the women are not exposed to smoke as much as in an open fire.
Everyone was very impressed with the stoves and asked a lot of questions about how to make them. There is some information available about them, but mostly in English. I'm going to try and write something in Spanish with some pictures and make it available to everyone. They are simple to build and not very expensive. I'm hoping someone in the community would be interested in making them and selling them locally which would be a good way to make them more available.
There is also a commercial model available called an “ecostove” that is made from cement. I just became aware of it the day of the workshop and wasn't able to find one to demonstrate, but I'll try to get the local staff of Food for the Hungry to buy one and see how it works. If they are not too expensive they may also be an alternative.
Things moved slowly here and it was then time for a break. I still wanted to talk about other topics like SODIS solar disinfection using UV rays, water filters and “cocinas mejoradas”, but time was running out. The hosts of the workshop scheduled some other activities and when I finally got to speak again I only had about a half hour to cover the rest of the material. I really galloped through it, and promised to send them some material later and then was done.
In summary, I think the workshop was a success. I put a lot of emphasis on accurate water testing and I think the participants understood that. I told them that the health and perhaps lives of people now depended on them to do their jobs well. I said that I was always available to help them and gave them all my email address, and I'll also write them with materials so we can keep in touch. I think follow up with them is very important as well and to encourage them to use the new knowledge they have.
Then I went back to the hotel and took a long nap!
Sunday, October 31, 2010
Some Amazing Days
I haven't written for the blog for several days now, I've been caught up in giving my water testing workshop. It's been a fabulous, rewarding experience, but exhausting and somewhat overwhelming. I didn't get much sleep on Wednesday or Thursday nights and now finally on Saturday morning I've gotten enough rest and time to be able to think clearly and try and put down some of what happened.
One issue has been that my team partner Stan and I have very different interests and objectives for our work. Food for the Hungry has received requests from different remote villages for help with their water systems, whether wells or springs or pumps or whatever. Stan then is sent out to check them out, a long process that takes most of the day, and two interpreters. They try to coordinate our projects with Stan's, so it sometimes turns out that we are kind of stuck in someplace waiting till he finishes his work. I had a lot of prep work to do prior to the workshop, so I asked for time to work in the office, and on Wednesday their staff had a meeting to attend so they just gave me their keys. Susan and I spent the day there working getting ready for Thursday. Because I decided to use their projector and do a power point show rather than just hold up pictures, Susan had to photograph some of my things that weren't in the computer then down load them. They looked a little funny, but were the best we could do. I wanted everything to be both in English and Spanish and so had to write some Spanish titles on the fly. I'm definitely not a power point person and it took an exceedingly long time to put the show together. If I had had time before I left to prepare I'd have felt more secure.
I couldn't sleep Wednesday night fussing and organizing and I had a big stack of papers and handouts I'd prepared to get sorted. I worried that I hadn't tried the projector with my computer and program, so I made copies of it in various formats. I copied it to a zip drive so that possibly I could use another computer if mine was compatible. I also was worried that inadequate information had gone out to the participants in advance. I wanted everyone to bring cardboard so that we could make stoves. Susan didn't think that they had access to cardboard boxes and that we might have to find a different material, but I was hopeful that there would be enough for at least a few stoves. Also it has been cloudy and overcast a lot and I was worried that the solar stove display would be a bust. I finally got up at about 4:00 and went over my speech trying to translate my thoughts into understandable Spanish. The only good sign was that there was plenty of hot water for a shower and I didn't cut myself shaving!
It's about a half hour drive from town to the resort where the workshop was held. Guatemala is an incredibly poor country, but there must be some rich people because this resort was almost as nice as any in the States. It covered several acres with gardens and pools and their own zoo of native animals. They had several fancy restaurants and very nice coffee service for our group. We got there about 8:30 and there were already 15 or 20 people waiting for a 10:00 start. At first there was no electricity, then no extension cord, but the lady doctor with Food for the Hungry also was going to use the projector and she had a little temper tantrum and immediately a cord appeared. I had a lot of of stuff to set up, but the director of the program caught me off guard by saying since everyone was there early, they might as well get started an hour early! There was nothing to do but grab my notes and plunge in!
At first my speech is just about how many people suffer from contaminated drinking water and the bad effects it has, especially on children. The audience was interested but not enthusiastic, I think they had heard that part before. Then though I start getting more technical and complicated as I start to plow into basic bacteriology. I want the participants to be knowledgeable about what they are doing and not just guess at the results, and it obviously was a new topic for some of them. I think some people didn't even know there were bacteria. I think next time I’ll have a slide that shows the relative size of things. We talked about what bacteria and viruses were and how they grow. Then we went into the various diseases and why you need an indicator for contamination. People were definitely sitting up in their seats then.
After all that I pull out some petrifilms and some tubes and we start looking at samples and talking about which are positive and why. I always struggle with the explanations in Spanish and then a person was translating my Spanish into the indian language. It slowed things down, but gave me time to think about my next sentence so it was all right.
By that time people had been sitting for an hour so I had everyone get up and we practiced pipetting. The little plastic droppers actually are a little trick for people to get used to, and they have to pipet exactly one ml of water on the Petrifilms, using the markings on the dropper. Usually we mix some coffer or coke with the water so it is more visible and then everyone gets a chance. I think people seemed to be having fun.
After everyone feels comfortable with the pipets we get started with the setup. I passed out Petrifilms and Colilert tubes, but I had a hard time keeping people from opening them up. First I talked about the importance of labeling and record keeping. Even though they only had one sample today, it is important to stay organized and accurate. I taught them how to open the pipet package without contaminating the tip and then to carefully open the tube. After we filled the tube to 10mls we replaced the top and mixed it well. Then I demonstrated how to carefully draw up one ml of water and put it in the center of the Petrifilm and very slowly replace the covering. This is sort of a trick also and several people had to try again before they got the knack of it. We used my petrifilms because I wanted them to start their work with a complete kit of supplies.
Of course then comes the big joke of the morning when I demonstrate how to incubate the samples under their clothes. I told them that for tonight this was their spouse and they were going to sleep with them all night in their beds. Then we got serious about how bacteria need the right temperature – body temperature- to grow. I gave everyone a ziplock bag and after some joking around every one put their samples in the bags and put them inside their clothing, including some of the women. Then we had a very nice lunch in the resort restaurant.
A minor problem was that everything moves slowly and happens when people want it to, so I fuss with the projectors and organize handouts, but everything starts 45 minutes late, except when I'm not prepared. Eventually I started out by talking about the risk of drinking water contaminated by bacteria and ask how that could be prevented. One simple way is to heat the water before drinking. The water need not be boiled because I show that harmful organisms are killed at temperatures well below that level. I show the WAPI chart and then explain how the WAPI works, how it can be reused and we pass some of them around to look at.
Meanwhile I had Susan setting up the solar stove and heating the water outside. We all got up and went out to see her display. Miraculously when she took the top of the pot off, the wax had melted. I brought along a digital thermometer and showed that the temperature was well above 65 degrees. I let Susan do this part of the program and she did quite well. Everyone has to touch the pot to prove t themselves that it's hot and then for dramatic effect I mixed a cup of the hot water with some Nescafe and drank it to show that I was confidant that the water was safe.
People seemed quite impressed with the stove, but have a hard time believing that they can be simply made, so the final part of the day is to have the participants form small groups and make solar stoves themselves out of cardboard and tin foil. Most tried to trace my Cookit stove even though I had lots of pictures of different stoves they could make. I think next time I'll hide mine to force them to create their own. It's a fun activity with everyone down on the floor cutting cardboard and gluing foil on it, it reminds me of a 3rd grade art project. At the end of the day everyone sets up their stoves to dry and we leave. I should try to work in a summary session at that time, but everyone is scattered and tired.
So that was Thursday, the microbiology lesson and sample set up, followed by a solar stove building session. On Friday we will examine the samples and go from there.
One issue has been that my team partner Stan and I have very different interests and objectives for our work. Food for the Hungry has received requests from different remote villages for help with their water systems, whether wells or springs or pumps or whatever. Stan then is sent out to check them out, a long process that takes most of the day, and two interpreters. They try to coordinate our projects with Stan's, so it sometimes turns out that we are kind of stuck in someplace waiting till he finishes his work. I had a lot of prep work to do prior to the workshop, so I asked for time to work in the office, and on Wednesday their staff had a meeting to attend so they just gave me their keys. Susan and I spent the day there working getting ready for Thursday. Because I decided to use their projector and do a power point show rather than just hold up pictures, Susan had to photograph some of my things that weren't in the computer then down load them. They looked a little funny, but were the best we could do. I wanted everything to be both in English and Spanish and so had to write some Spanish titles on the fly. I'm definitely not a power point person and it took an exceedingly long time to put the show together. If I had had time before I left to prepare I'd have felt more secure.
I couldn't sleep Wednesday night fussing and organizing and I had a big stack of papers and handouts I'd prepared to get sorted. I worried that I hadn't tried the projector with my computer and program, so I made copies of it in various formats. I copied it to a zip drive so that possibly I could use another computer if mine was compatible. I also was worried that inadequate information had gone out to the participants in advance. I wanted everyone to bring cardboard so that we could make stoves. Susan didn't think that they had access to cardboard boxes and that we might have to find a different material, but I was hopeful that there would be enough for at least a few stoves. Also it has been cloudy and overcast a lot and I was worried that the solar stove display would be a bust. I finally got up at about 4:00 and went over my speech trying to translate my thoughts into understandable Spanish. The only good sign was that there was plenty of hot water for a shower and I didn't cut myself shaving!
It's about a half hour drive from town to the resort where the workshop was held. Guatemala is an incredibly poor country, but there must be some rich people because this resort was almost as nice as any in the States. It covered several acres with gardens and pools and their own zoo of native animals. They had several fancy restaurants and very nice coffee service for our group. We got there about 8:30 and there were already 15 or 20 people waiting for a 10:00 start. At first there was no electricity, then no extension cord, but the lady doctor with Food for the Hungry also was going to use the projector and she had a little temper tantrum and immediately a cord appeared. I had a lot of of stuff to set up, but the director of the program caught me off guard by saying since everyone was there early, they might as well get started an hour early! There was nothing to do but grab my notes and plunge in!
At first my speech is just about how many people suffer from contaminated drinking water and the bad effects it has, especially on children. The audience was interested but not enthusiastic, I think they had heard that part before. Then though I start getting more technical and complicated as I start to plow into basic bacteriology. I want the participants to be knowledgeable about what they are doing and not just guess at the results, and it obviously was a new topic for some of them. I think some people didn't even know there were bacteria. I think next time I’ll have a slide that shows the relative size of things. We talked about what bacteria and viruses were and how they grow. Then we went into the various diseases and why you need an indicator for contamination. People were definitely sitting up in their seats then.
After all that I pull out some petrifilms and some tubes and we start looking at samples and talking about which are positive and why. I always struggle with the explanations in Spanish and then a person was translating my Spanish into the indian language. It slowed things down, but gave me time to think about my next sentence so it was all right.
By that time people had been sitting for an hour so I had everyone get up and we practiced pipetting. The little plastic droppers actually are a little trick for people to get used to, and they have to pipet exactly one ml of water on the Petrifilms, using the markings on the dropper. Usually we mix some coffer or coke with the water so it is more visible and then everyone gets a chance. I think people seemed to be having fun.
After everyone feels comfortable with the pipets we get started with the setup. I passed out Petrifilms and Colilert tubes, but I had a hard time keeping people from opening them up. First I talked about the importance of labeling and record keeping. Even though they only had one sample today, it is important to stay organized and accurate. I taught them how to open the pipet package without contaminating the tip and then to carefully open the tube. After we filled the tube to 10mls we replaced the top and mixed it well. Then I demonstrated how to carefully draw up one ml of water and put it in the center of the Petrifilm and very slowly replace the covering. This is sort of a trick also and several people had to try again before they got the knack of it. We used my petrifilms because I wanted them to start their work with a complete kit of supplies.
Of course then comes the big joke of the morning when I demonstrate how to incubate the samples under their clothes. I told them that for tonight this was their spouse and they were going to sleep with them all night in their beds. Then we got serious about how bacteria need the right temperature – body temperature- to grow. I gave everyone a ziplock bag and after some joking around every one put their samples in the bags and put them inside their clothing, including some of the women. Then we had a very nice lunch in the resort restaurant.
A minor problem was that everything moves slowly and happens when people want it to, so I fuss with the projectors and organize handouts, but everything starts 45 minutes late, except when I'm not prepared. Eventually I started out by talking about the risk of drinking water contaminated by bacteria and ask how that could be prevented. One simple way is to heat the water before drinking. The water need not be boiled because I show that harmful organisms are killed at temperatures well below that level. I show the WAPI chart and then explain how the WAPI works, how it can be reused and we pass some of them around to look at.
Meanwhile I had Susan setting up the solar stove and heating the water outside. We all got up and went out to see her display. Miraculously when she took the top of the pot off, the wax had melted. I brought along a digital thermometer and showed that the temperature was well above 65 degrees. I let Susan do this part of the program and she did quite well. Everyone has to touch the pot to prove t themselves that it's hot and then for dramatic effect I mixed a cup of the hot water with some Nescafe and drank it to show that I was confidant that the water was safe.
People seemed quite impressed with the stove, but have a hard time believing that they can be simply made, so the final part of the day is to have the participants form small groups and make solar stoves themselves out of cardboard and tin foil. Most tried to trace my Cookit stove even though I had lots of pictures of different stoves they could make. I think next time I'll hide mine to force them to create their own. It's a fun activity with everyone down on the floor cutting cardboard and gluing foil on it, it reminds me of a 3rd grade art project. At the end of the day everyone sets up their stoves to dry and we leave. I should try to work in a summary session at that time, but everyone is scattered and tired.
So that was Thursday, the microbiology lesson and sample set up, followed by a solar stove building session. On Friday we will examine the samples and go from there.
Tuesday, October 26, 2010
Climbing the hills
Monday started out really early, about 6:30 for breakfast in the hotel dining room. I'm not sure but they seem to be the slowest restaurant I've ever been in, even coffee takes 10-15 minutes. The other side of it was that even though our minder said she wanted to be going by 7:30 it was really closer to 8:30 by the time we actually left.
We drove to a small town a few miles from Cobán, San Juan Chamelco, where the head offices of Food for the Hungry are located and met the local Director Shane Hoffner and his wife Cali. They are both young and just learning Spanish, but seemed very dedicated and competent. His background is Civil Engineering and hers is Health Promotion, so they have good backgrounds for their work. We were only in the office for a few minutes and I was racing around to get the supplies for my had washing demonstration. We had purchased some soap and nylon stockings to put the soap in the night before and a bottle to use for the “tippytap” demonstration. Then we all piled back into the van for a trip on a very rough road to a small mountain community where the health promotion was taking place.
When we arrived they were already involved in the program, with a very animated woman giving an pep talk on hand washing to about 60 ladies from the area. She was speaking in the local native indian language and the woman were paying very close attention and responding to her talk. She was in modern dress but the audience women were all dressed in very elaborate, traditional costumes There were many that were hand embroidered, and some in traditional styles but using modern materials. The clothes were beautiful and I took a number of photos of them, which they seemed to be proud to pose for.
After the lady spoke, Cali, Shane's wife spoke. She is a beginning Spanish speaker but gamely gave a talk about hand washing and children, then did the old trick of putting hand lotion on her hands then glitter. Then by shaking hands with another person, some of the glitter and lotion came off on that persons hands who shook anothers hands and glitter came off again and the third person, and so on. It's a simple but effective game to play to demonstrate how bacteria are transferred from person to person. Next I did my demonstration with my water bottle. We used the same ladies to show that washing can remove the glitter/bacteria. I spoke in Spanish then someone translated it into the Indian dialect. It went okay, but my point was that it didn't use much water, and most of the women in the audience had running water in their homes and didn't need to conserve. It rains a lot and there are lots of springs so many villages have some sort of water system. The part about washing the glitter off their hands made more sense to them, it had a practical purpose. In all, I thought my presentation was sort of lame next to the ladies talk. She then followed my with an elaborate skit about a baby with diarrhea and had everyone's complete attention.
After I spoke I set up the solar stove outside to try it out. In my rush to get going I didn't bring a small pot so the one I ended up with was too large to heat up the water quickly, but the outside of the pot got hot. The ladies were really interested and crowded around wanting to know how it worked, so Susan and I took turns explaining it. That turned out to be the big hit of the day, so that was good. There is a lot of cloudy weather and rain and many people feel that a solar stove can only be a backup to wood burning. There is quite a lot of deforestation going on so that is a big issue.
Stan Withee was there looking at the water system. They have a chlorination system there but it doesn't work very well and they don't know how to manage it. Stan collected a sample for me to test for bacteria.
After that Stan and Shane were going out to look at a couple of other water systems and asked if I wanted to go along. With such short notice Susan and I had to race around to get our stuff collected and we got scattered . I ended up leaving my pack with my water bottle and laptop with Susan and took off in the van. We went to another community further up the road. They had a system where they had to pump water up to a high distribution tank. It was very expensive to run and didn't provide enough water for the people. The question was whether the pumps were working right or whether there were leaks in the system.
We hiked up the whole length of the pipe through very dense brush to measure the distance to the upper tank. The local men guided us up the hill, chopping the brush with machetes. There were beautiful flowers and plants everywhere but it was a struggle and very slippery and muddy from the rain. On top we took GPS measurements of the elevation and checked the tank. Everything seemed to be okay with their water system. Stan offered advice to them about simple things like making sure there were no leaking water faucets at peoples homes, or that they make sure they don't overfill the tanks and waste water they have pumped. He also examined their pumps to see that they were working adequately.
I thought that they had a very sophisticated and complicated system for such a small community, but that they seemed very comfortable with running it.
We then looked at another community even further up the road at a higher elevation. Our van couldn't climb the steep road and so we ended up walking up to the houses. There was no electricity there and the only year round functioning spring was below the homes, and it was small so there was no opportunity to pump adequate water up to the homes. The best that Stan could offer was to do a simple survey to show where the water pipe could be brought out to the edge of the road so that they could have a more convenient tank to store their water. Also we made suggestions about how to fence off the area to keep animals out and to cover the spring so that mud and debris didn't get into the water. We also took a sample to check for bacteria.
We finally got back to Cobán about 6 pm. I was really tired and muddy from all the climbing, plus I had several water samples to set up and incubate. It had been a long day, but it was fun. We rested for a while and took showers and got to bed about 11. I'm still concerned about my workshop on Thursday and need to go to the mercado to look for stove parts to build a rocket stove for a demonstration. I hope we will have time on Tuesday to look.
We drove to a small town a few miles from Cobán, San Juan Chamelco, where the head offices of Food for the Hungry are located and met the local Director Shane Hoffner and his wife Cali. They are both young and just learning Spanish, but seemed very dedicated and competent. His background is Civil Engineering and hers is Health Promotion, so they have good backgrounds for their work. We were only in the office for a few minutes and I was racing around to get the supplies for my had washing demonstration. We had purchased some soap and nylon stockings to put the soap in the night before and a bottle to use for the “tippytap” demonstration. Then we all piled back into the van for a trip on a very rough road to a small mountain community where the health promotion was taking place.
When we arrived they were already involved in the program, with a very animated woman giving an pep talk on hand washing to about 60 ladies from the area. She was speaking in the local native indian language and the woman were paying very close attention and responding to her talk. She was in modern dress but the audience women were all dressed in very elaborate, traditional costumes There were many that were hand embroidered, and some in traditional styles but using modern materials. The clothes were beautiful and I took a number of photos of them, which they seemed to be proud to pose for.
After the lady spoke, Cali, Shane's wife spoke. She is a beginning Spanish speaker but gamely gave a talk about hand washing and children, then did the old trick of putting hand lotion on her hands then glitter. Then by shaking hands with another person, some of the glitter and lotion came off on that persons hands who shook anothers hands and glitter came off again and the third person, and so on. It's a simple but effective game to play to demonstrate how bacteria are transferred from person to person. Next I did my demonstration with my water bottle. We used the same ladies to show that washing can remove the glitter/bacteria. I spoke in Spanish then someone translated it into the Indian dialect. It went okay, but my point was that it didn't use much water, and most of the women in the audience had running water in their homes and didn't need to conserve. It rains a lot and there are lots of springs so many villages have some sort of water system. The part about washing the glitter off their hands made more sense to them, it had a practical purpose. In all, I thought my presentation was sort of lame next to the ladies talk. She then followed my with an elaborate skit about a baby with diarrhea and had everyone's complete attention.
After I spoke I set up the solar stove outside to try it out. In my rush to get going I didn't bring a small pot so the one I ended up with was too large to heat up the water quickly, but the outside of the pot got hot. The ladies were really interested and crowded around wanting to know how it worked, so Susan and I took turns explaining it. That turned out to be the big hit of the day, so that was good. There is a lot of cloudy weather and rain and many people feel that a solar stove can only be a backup to wood burning. There is quite a lot of deforestation going on so that is a big issue.
Stan Withee was there looking at the water system. They have a chlorination system there but it doesn't work very well and they don't know how to manage it. Stan collected a sample for me to test for bacteria.
After that Stan and Shane were going out to look at a couple of other water systems and asked if I wanted to go along. With such short notice Susan and I had to race around to get our stuff collected and we got scattered . I ended up leaving my pack with my water bottle and laptop with Susan and took off in the van. We went to another community further up the road. They had a system where they had to pump water up to a high distribution tank. It was very expensive to run and didn't provide enough water for the people. The question was whether the pumps were working right or whether there were leaks in the system.
We hiked up the whole length of the pipe through very dense brush to measure the distance to the upper tank. The local men guided us up the hill, chopping the brush with machetes. There were beautiful flowers and plants everywhere but it was a struggle and very slippery and muddy from the rain. On top we took GPS measurements of the elevation and checked the tank. Everything seemed to be okay with their water system. Stan offered advice to them about simple things like making sure there were no leaking water faucets at peoples homes, or that they make sure they don't overfill the tanks and waste water they have pumped. He also examined their pumps to see that they were working adequately.
I thought that they had a very sophisticated and complicated system for such a small community, but that they seemed very comfortable with running it.
We then looked at another community even further up the road at a higher elevation. Our van couldn't climb the steep road and so we ended up walking up to the houses. There was no electricity there and the only year round functioning spring was below the homes, and it was small so there was no opportunity to pump adequate water up to the homes. The best that Stan could offer was to do a simple survey to show where the water pipe could be brought out to the edge of the road so that they could have a more convenient tank to store their water. Also we made suggestions about how to fence off the area to keep animals out and to cover the spring so that mud and debris didn't get into the water. We also took a sample to check for bacteria.
We finally got back to Cobán about 6 pm. I was really tired and muddy from all the climbing, plus I had several water samples to set up and incubate. It had been a long day, but it was fun. We rested for a while and took showers and got to bed about 11. I'm still concerned about my workshop on Thursday and need to go to the mercado to look for stove parts to build a rocket stove for a demonstration. I hope we will have time on Tuesday to look.
Sunday, October 24, 2010
Cobán
On Sunday morning we had a nice breakfast at the small pension where we stayed. It was a little distance from the airport and the streets are a little rough and confusing so I don't know exactly where we were. After breakfast we went to look at a different hotel that Roger Capps group will be staying in when they arrive. It really didn't look very clean so then we went to another hotel that our guide from Medical Teams recommended. It was really much better and about the same price so I wrote to Roger and to the person from Child Aid who is in charge of his trip with that info.
Guatemala City is large and spread out like Mexico City but seems to lack attractive central areas like parks or plazas. At least I didn't see any as we drove through town on our way out to Cobán. Cobán is about 4 or 5 hours away in the mountains. The climate is cooler and cloudier, sort of like Oregon but with a few palm trees. We passed through an area known as a bioreserve where some species of birds and plants are protected, like the Quetzal, Guatemala's national bird.
Near the bioreserve is a hotel resort complex called the Park Hotel. It's where we are going to have my workshop on Thursday and Friday. It's very nice and upscale, the fanciest place I've held a workshop. It's a little intimidating, I hope we get enough people to justify the expense.
In Cobán we met up with Stan Withee my teammate. He's been here a week surveying water systems in the small communities. He's a water engineer and has been climbing up and down the hills laying out pipe lines and examining springs and other water sources. He has a number of water samples for me to test so that he can report back to the people he helped.
Apparently we are scheduled to go to a health fair tomorrow in a community. The first part is a talk from a health nurse about hand washing and I suggested that we bring a hand washing station – called a tippytap- to show. It's just a plastic bottle with a few holes in it, plus a soap in a nylon stocking, but it works very well and is a good demonstration. In Mexico I gave out small geraniums with the tippytap which made them much more desirable. I'd thought about including it in the Friday lecture, so I guess I can try out my speech tomorrow.
In the afternoon I'm supposed to take some water samples as a demonstration for the community and bring the results back the next day. The only problem is that it sometimes takes more than 24 hours so I hope I have some results to show.
I've still got a ton of unpacking to do to get ready for tomorrow, so I'll sign off.
Let me know if you're reading this blog, and what your opinions are.
tom
Guatemala City is large and spread out like Mexico City but seems to lack attractive central areas like parks or plazas. At least I didn't see any as we drove through town on our way out to Cobán. Cobán is about 4 or 5 hours away in the mountains. The climate is cooler and cloudier, sort of like Oregon but with a few palm trees. We passed through an area known as a bioreserve where some species of birds and plants are protected, like the Quetzal, Guatemala's national bird.
Near the bioreserve is a hotel resort complex called the Park Hotel. It's where we are going to have my workshop on Thursday and Friday. It's very nice and upscale, the fanciest place I've held a workshop. It's a little intimidating, I hope we get enough people to justify the expense.
In Cobán we met up with Stan Withee my teammate. He's been here a week surveying water systems in the small communities. He's a water engineer and has been climbing up and down the hills laying out pipe lines and examining springs and other water sources. He has a number of water samples for me to test so that he can report back to the people he helped.
Apparently we are scheduled to go to a health fair tomorrow in a community. The first part is a talk from a health nurse about hand washing and I suggested that we bring a hand washing station – called a tippytap- to show. It's just a plastic bottle with a few holes in it, plus a soap in a nylon stocking, but it works very well and is a good demonstration. In Mexico I gave out small geraniums with the tippytap which made them much more desirable. I'd thought about including it in the Friday lecture, so I guess I can try out my speech tomorrow.
In the afternoon I'm supposed to take some water samples as a demonstration for the community and bring the results back the next day. The only problem is that it sometimes takes more than 24 hours so I hope I have some results to show.
I've still got a ton of unpacking to do to get ready for tomorrow, so I'll sign off.
Let me know if you're reading this blog, and what your opinions are.
tom
Saturday, October 23, 2010
First Night in Guatemala City
Susan and I arrive here in Guatemala City after a nice flight from Portland to Houston and then on to here. We'll stay overnight here and leave in the morning for Cobán, about four hours away by bus. It's supposed to be a beautiful place with lots of flowers and birds, including the Quetzal, the national bird. It's a sort of beautiful parrot with a long trailing tail.
I talked yesterday about the very short time we'll actually be here, just two weeks to visit many different small communities. I don't like that in one way, I don't want to be a visiting authority who comes in for a short visit, doesn't really understand the situation or the communities needs, makes some pronouncements and leaves. I'm going to try and not make myself seem all knowing and smarter than I really am. I'm expecting to learn more than I teach.
Someone once made a good observation to me that I really liked. When Americans volunteer for service projects like the one Susan and I are on, we sometimes think of ourselves as knowing a lot and coming to teach others who know less than us. We are on a higher plane and the people we are serving are down on a lower level. We are going to hand down our wisdom and the people will gratefully accept it. It's certainly easy to think like that when you see extreme poverty and illness, especially if you think you know ways to alleviate it.
That person put it differently. He said that instead it was more like a mutual sharing. That these people had ideas and skills just as valuable to teach us. He tells the people that he is working with that Americans need help, they need the skills and values that they have and that the Americans are coming to learn from them. Americans have lost the sense of family, the sense of sharing and community that these people have and they need the lessons that they can teach. That is a trade, not a one way transfer and no charity is involved.
When the interaction between volunteer groups and local communities is seen in that way, there is more of a mutual respect and sense of value in what each offers. I try to keep that observation in my mind at all times, and I try to listen more than I talk. I've certainly learned a lot about people and human values on the trips I have done, and I've hoped to share a little of what I know that can help someone else.
I'm really looking forward to this new learning experience!
Tom
I talked yesterday about the very short time we'll actually be here, just two weeks to visit many different small communities. I don't like that in one way, I don't want to be a visiting authority who comes in for a short visit, doesn't really understand the situation or the communities needs, makes some pronouncements and leaves. I'm going to try and not make myself seem all knowing and smarter than I really am. I'm expecting to learn more than I teach.
Someone once made a good observation to me that I really liked. When Americans volunteer for service projects like the one Susan and I are on, we sometimes think of ourselves as knowing a lot and coming to teach others who know less than us. We are on a higher plane and the people we are serving are down on a lower level. We are going to hand down our wisdom and the people will gratefully accept it. It's certainly easy to think like that when you see extreme poverty and illness, especially if you think you know ways to alleviate it.
That person put it differently. He said that instead it was more like a mutual sharing. That these people had ideas and skills just as valuable to teach us. He tells the people that he is working with that Americans need help, they need the skills and values that they have and that the Americans are coming to learn from them. Americans have lost the sense of family, the sense of sharing and community that these people have and they need the lessons that they can teach. That is a trade, not a one way transfer and no charity is involved.
When the interaction between volunteer groups and local communities is seen in that way, there is more of a mutual respect and sense of value in what each offers. I try to keep that observation in my mind at all times, and I try to listen more than I talk. I've certainly learned a lot about people and human values on the trips I have done, and I've hoped to share a little of what I know that can help someone else.
I'm really looking forward to this new learning experience!
Tom
Thursday, October 21, 2010
Guatemala Health Survey
It's been a while since I last posted on this blog, I usually try to focus on my current activities and projects. My wife Susan and I are leaving on Saturday, October 23 for Guatemala for a month of work. We are scheduled to meet with representatives of two organizations, Medical Teams International and Food for the Hungry. We'll be staying with them and helping do a health survey in a number of small communities is the central highlands of Guatemala.
Nearly two million children world wide die annually from drinking contaminated water. Most of my interest is is simple, low tech things families can do for themselves to make their water safe and protect their own health. Others can promote larger scale programs like wells and water systems, but I find that these projects are often expensive and complicated and a long time coming. Meanwhile children and families suffer from easily preventable diseases.
The kinds of questions I'll be asking include how many of the families have an adequate latrine or toilet. How is the drinking water in the community and has it been tested for contamination. How do families cook their meals, and what do they use, gas?, charcoal? wood? What is their overall health like.
The next questions are about what do the people there see as problems and what would they like to change? What are their priorities? Also, are there positive things about their communities and their lives that they want to preserve?
Then the question is what are their resources to make changes. Can the community help with money or labor? Is there leadership in the community to guide the work to completion? What about long term follow up?
I try not to impose my ideas on the people I'm working with, but try to understand their concerns and offer suggestions if asked. I'm hoping rather for discussions about their interests and their ideas about solutions. I can then perhaps offer different ideas that they could consider.
We'll see how all this will go! On top of all the logistical, cultural and language barriers there will only be a short amount of time to actually talk to people and listen to their ideas. I expect that I will get far more out of the visit than the people I meet. Hopefully I'll be able to bring back some ideas and perhaps develop some ideas for future projects.
In addition to working and report writing, I'll try to maintain this blog of my activities and I'll be happy to hear opinions from you about what I'm doing. You can also check out my Agua Pura website at http://aguapuraparaelpueblo.org/
watertestingTom
Nearly two million children world wide die annually from drinking contaminated water. Most of my interest is is simple, low tech things families can do for themselves to make their water safe and protect their own health. Others can promote larger scale programs like wells and water systems, but I find that these projects are often expensive and complicated and a long time coming. Meanwhile children and families suffer from easily preventable diseases.
The kinds of questions I'll be asking include how many of the families have an adequate latrine or toilet. How is the drinking water in the community and has it been tested for contamination. How do families cook their meals, and what do they use, gas?, charcoal? wood? What is their overall health like.
The next questions are about what do the people there see as problems and what would they like to change? What are their priorities? Also, are there positive things about their communities and their lives that they want to preserve?
Then the question is what are their resources to make changes. Can the community help with money or labor? Is there leadership in the community to guide the work to completion? What about long term follow up?
I try not to impose my ideas on the people I'm working with, but try to understand their concerns and offer suggestions if asked. I'm hoping rather for discussions about their interests and their ideas about solutions. I can then perhaps offer different ideas that they could consider.
We'll see how all this will go! On top of all the logistical, cultural and language barriers there will only be a short amount of time to actually talk to people and listen to their ideas. I expect that I will get far more out of the visit than the people I meet. Hopefully I'll be able to bring back some ideas and perhaps develop some ideas for future projects.
In addition to working and report writing, I'll try to maintain this blog of my activities and I'll be happy to hear opinions from you about what I'm doing. You can also check out my Agua Pura website at http://aguapuraparaelpueblo.org/
watertestingTom
Sunday, April 18, 2010
Sand Filtration Systems
Sand Filtration Systems
Recently I have been studying and writing about various methods for disinfection of water . Since I first learned about solar stoves, I have made a number of them in different designs and have also given several workshops about how to make them. Solar stoves have the capacity to heat water to temperatures adequate for Pasteurization, and small temperature indicators can verify that. Of all the methods available this one of the few that has a secure endpoint, positive proof that each batch of water has been disinfected. Other methods can only assume that the water is safe, based on previous experience. Dr. Metcalf who developed the testing methods I advocate calls this “evidence based versus faith based methodologies”.
Sand filtration systems are in this category. When working correctly they are effective and produce a fair volume of water. They have many possible defects however and require proper setup and maintenance to work safely.
One organization, Aqua Clara, has designed a small sand filtration system that seems simple enough and inexpensive enough to be used by families . It is designed to be constructed in a plastic garbage can or similar sized container, and uses PVC pipe for the internal piping. At the bottom of the container is a layer of gravel or small stones, larger than the hole sizes in the pickup tube running across the bottom. Above that layer is one of finer gravel. On top of that second layer is a thin layer of a metallic biocide, a material that kills bacteria. Finally, above that is a layer of fine sand. Thus there are at least 4 layers from bottom to top of increasingly fine sand material. In practice a layer of active bacteria and yeasts slowly forms on the surface of the sand, called a “schmutdecke” in German. This bioactive layer also helps to kill or inactivate pathogenic organisms.
The principal of the sand filter is that contaminated material slowly passes down through the schmutdecke and the very fine sand and the contaminants get trapped in the pores and interstitial spaces between the sand grains. There is also some biological activity killing pathogens in the sand layer. Any pathogenic materials that make it through the sand layers are killed when they pass through the biocide layer. Finally water pressure from above forces the clean, decontaminated water up and out the outlet pipe.
Aqua Clara suggests that the sand layers be put down very evenly and carefully so that no small channels develop through the sand, thus allowing the water to pass though without being filtered adequately. Operating properly they say it should take up to 24 hours for water to filter from the top to the bottom. Also, to be effective it make take several weeks for the bioactive schmutdecke to develop and the water may not be completely decontaminated or safe until that time.
After studying the informational material provided by Aqua Clara, I decided to try and make a small sand filter model that would demonstrate the principal of the system. I wanted something that I could take with me as an example for people to examine. I also wanted to test the methods of construction that Aqua Clara use to make their filters. After learning and practicing their procedures by making a model, I planned then to make a full size filter similar to theirs and test it for effectiveness.
I had some coarse sand from previous projects so I made two sifting screens similar to Aqua Clara's instructions and sifted the sand into three sizes: small gravel, course and fine sand. After sieving the sand into the three sizes I washed the sand to remove dirt and impurities. The procedure is to take small quantities of sand and swirl them in water for a few seconds then pour off the dirty water while the sand settles back to the bottom. Usually several washes are required to get the sand reasonably clean. The sand is then spread out to dry on clean plastic tarps.
Because of all the sand and water, these filter systems are very heavy and difficult to move, so mine was made in a small waste basket, but when completed it still weighed over 30 pounds. I cut the front panel out of the waste basket and added a
piece of Plexiglas so people could
see the different layers inside. I
then cut and fitted ½ inch PVC pipe
to make the pickup tube and outlet
pipe.
It's important to place the layers carefully in the filter so that no air is trapped and the layers are even and well packed. Starting with the gravel layer on the bottom I placed the material around the pickup tube so that the openings were not blocked. After several inches of gravel came the layer of coarse sand. In practice these layers are put in with lots of water and stirred to settle so that no air is trapped and no channels develop through the sand. I didn't have any metallic biocide material, so I put in a thin layer of white sand to indicate that material. The final fine sand layer extends up to within an inch or two of the outlet tube so that the water level remains above the sand and the sand cannot dry out.
Due to weather and other commitments this whole project took me several weeks to complete, but turned out pretty well when done. My goal was to have it ready by the time of the World Water Day activities in Portland, I was scheduled to give a presentation and I wanted the filter for a display. I made up an exhibit that included the water filter and a solar reflector oven and some other things with explanations and I thought it went pretty well.
One small problem with the filter was that the different layers tended to sift together, especially when I moved the filter. In normal operation that would not be an issue, especially if the layers were well settled, but in this case where the layers are visible they don't look as clean and distinct. If I redo this filter or make another for display, perhaps I can put something like plastic wrap in between the layers to keep them separate.
Another issue is its weight of about 40 pounds. Maybe I could make a smaller filter that isn't so heavy or substitute some other lighter material for the sand, or I could just have a nice picture of the layers and have the filter itself empty.
My next goal is to make a full size filter in a large garbage can similar to the ones made by Aqua Clara. They are quite specific about every detail of the construction so I'll try to follow their instructions closely. I have a power-point of one of their training sessions so I can try to watch it as I work. I want to build it in my back yard and use rainwater from my roof to charge it. Originally I had planned to make it a simple system that just passed the rainwater directly through the filter, but Aqua Clara says the water has to be added slowly every twelve hours, so I guess I'll have to have a rainwater storage tank that I can then pipe to the filter at intervals. I'll try to build it this summer during the dry season so that it will be ready by next fall.
Aqua Clara International has been very helpful to me, sharing their methodologies and giving me the biocide material to test and use. There are other manufacturers of water filter systems, but Aqua Clara seems committed to designing systems that local communities can build and maintain for themselves and to transferring the technology to them. I appreciate their concept and I hope that I can support them in their work. This should be a really interesting project to complete for me. I'm anxious to see how it works and to test it for a while here at home. It's important to use things yourself that you advocate for others; to practice what you preach. Just as I've used and tried to improve the latrines I've built and cooked and drank the water from the stoves I've made, I want to build and use water filters before I promote them to others.
Recently I have been studying and writing about various methods for disinfection of water . Since I first learned about solar stoves, I have made a number of them in different designs and have also given several workshops about how to make them. Solar stoves have the capacity to heat water to temperatures adequate for Pasteurization, and small temperature indicators can verify that. Of all the methods available this one of the few that has a secure endpoint, positive proof that each batch of water has been disinfected. Other methods can only assume that the water is safe, based on previous experience. Dr. Metcalf who developed the testing methods I advocate calls this “evidence based versus faith based methodologies”.
Sand filtration systems are in this category. When working correctly they are effective and produce a fair volume of water. They have many possible defects however and require proper setup and maintenance to work safely.
One organization, Aqua Clara, has designed a small sand filtration system that seems simple enough and inexpensive enough to be used by families . It is designed to be constructed in a plastic garbage can or similar sized container, and uses PVC pipe for the internal piping. At the bottom of the container is a layer of gravel or small stones, larger than the hole sizes in the pickup tube running across the bottom. Above that layer is one of finer gravel. On top of that second layer is a thin layer of a metallic biocide, a material that kills bacteria. Finally, above that is a layer of fine sand. Thus there are at least 4 layers from bottom to top of increasingly fine sand material. In practice a layer of active bacteria and yeasts slowly forms on the surface of the sand, called a “schmutdecke” in German. This bioactive layer also helps to kill or inactivate pathogenic organisms.
The principal of the sand filter is that contaminated material slowly passes down through the schmutdecke and the very fine sand and the contaminants get trapped in the pores and interstitial spaces between the sand grains. There is also some biological activity killing pathogens in the sand layer. Any pathogenic materials that make it through the sand layers are killed when they pass through the biocide layer. Finally water pressure from above forces the clean, decontaminated water up and out the outlet pipe.
Aqua Clara suggests that the sand layers be put down very evenly and carefully so that no small channels develop through the sand, thus allowing the water to pass though without being filtered adequately. Operating properly they say it should take up to 24 hours for water to filter from the top to the bottom. Also, to be effective it make take several weeks for the bioactive schmutdecke to develop and the water may not be completely decontaminated or safe until that time.
After studying the informational material provided by Aqua Clara, I decided to try and make a small sand filter model that would demonstrate the principal of the system. I wanted something that I could take with me as an example for people to examine. I also wanted to test the methods of construction that Aqua Clara use to make their filters. After learning and practicing their procedures by making a model, I planned then to make a full size filter similar to theirs and test it for effectiveness.
I had some coarse sand from previous projects so I made two sifting screens similar to Aqua Clara's instructions and sifted the sand into three sizes: small gravel, course and fine sand. After sieving the sand into the three sizes I washed the sand to remove dirt and impurities. The procedure is to take small quantities of sand and swirl them in water for a few seconds then pour off the dirty water while the sand settles back to the bottom. Usually several washes are required to get the sand reasonably clean. The sand is then spread out to dry on clean plastic tarps.
Because of all the sand and water, these filter systems are very heavy and difficult to move, so mine was made in a small waste basket, but when completed it still weighed over 30 pounds. I cut the front panel out of the waste basket and added a
piece of Plexiglas so people could
see the different layers inside. I
then cut and fitted ½ inch PVC pipe
to make the pickup tube and outlet
pipe.
It's important to place the layers carefully in the filter so that no air is trapped and the layers are even and well packed. Starting with the gravel layer on the bottom I placed the material around the pickup tube so that the openings were not blocked. After several inches of gravel came the layer of coarse sand. In practice these layers are put in with lots of water and stirred to settle so that no air is trapped and no channels develop through the sand. I didn't have any metallic biocide material, so I put in a thin layer of white sand to indicate that material. The final fine sand layer extends up to within an inch or two of the outlet tube so that the water level remains above the sand and the sand cannot dry out.
Due to weather and other commitments this whole project took me several weeks to complete, but turned out pretty well when done. My goal was to have it ready by the time of the World Water Day activities in Portland, I was scheduled to give a presentation and I wanted the filter for a display. I made up an exhibit that included the water filter and a solar reflector oven and some other things with explanations and I thought it went pretty well.
One small problem with the filter was that the different layers tended to sift together, especially when I moved the filter. In normal operation that would not be an issue, especially if the layers were well settled, but in this case where the layers are visible they don't look as clean and distinct. If I redo this filter or make another for display, perhaps I can put something like plastic wrap in between the layers to keep them separate.
Another issue is its weight of about 40 pounds. Maybe I could make a smaller filter that isn't so heavy or substitute some other lighter material for the sand, or I could just have a nice picture of the layers and have the filter itself empty.
My next goal is to make a full size filter in a large garbage can similar to the ones made by Aqua Clara. They are quite specific about every detail of the construction so I'll try to follow their instructions closely. I have a power-point of one of their training sessions so I can try to watch it as I work. I want to build it in my back yard and use rainwater from my roof to charge it. Originally I had planned to make it a simple system that just passed the rainwater directly through the filter, but Aqua Clara says the water has to be added slowly every twelve hours, so I guess I'll have to have a rainwater storage tank that I can then pipe to the filter at intervals. I'll try to build it this summer during the dry season so that it will be ready by next fall.
Aqua Clara International has been very helpful to me, sharing their methodologies and giving me the biocide material to test and use. There are other manufacturers of water filter systems, but Aqua Clara seems committed to designing systems that local communities can build and maintain for themselves and to transferring the technology to them. I appreciate their concept and I hope that I can support them in their work. This should be a really interesting project to complete for me. I'm anxious to see how it works and to test it for a while here at home. It's important to use things yourself that you advocate for others; to practice what you preach. Just as I've used and tried to improve the latrines I've built and cooked and drank the water from the stoves I've made, I want to build and use water filters before I promote them to others.
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