Freddy Mamani studies the operation of the McGuire Water Purifier, which uses the chlorine from ordinary table salt to purify water. The device is hung at an angle on purpose; the slight tilt increases its efficiency, according to the manufacturer. (T-G Photo by John I. Carney) [Click to enlarge]

Previously: Part 1 | Part 2 | Part 3

COCHABAMBA, Bolivia -- New Life International, a non-profit Christian group based in Indiana, produces a briefcase-sized device called a McGuire Water Purifier.

It's a U-shaped plastic tube. In one leg of the "U," you pour salt water, and seal the top of the tube with a plug. The other end of the "U" is also filled with water, either with just a pinch of salt or with some sodium hydroxide (lye) left over from a previous usage of the device. The device is hung from a nail so that it's tilted slightly, with the lye end higher.

When you hook up the purifier to a normal 12-volt car battery, it begins to bubble. What happens is that an electrified metal plate in the bottom of the "U" creates a chemical reaction. Chlorine gas is being liberated from the salt water. The sodium atoms released by this reaction penetrate the plate somehow and migrate to the other side of the tube, where they combine with hydrogen and oxygen to form sodium hydroxide.

The chlorine gas captured in the salt water side of the device is then carried away by a plastic tube. At the end of that plastic tube is a submersible pump which pulls the gas through. The pump can be powered by the same battery which runs the cholorinator.

If you take the submersible pump and drop it into a large holding tank of water, it will create a stream of chlorine bubbles which chlorinate the water, killing microorganisms immediately and leaving enough residual chlorine to keep the water safe for many hours to come. In just one minute, the McGuire Water Purifier can chlorinate a 50-gallon drum full of water. You must wait an hour for the chlorine to have its full effect and for some of the unpleasant smell and taste to dissipate, but at that point you have typhoid-free drinking water.

New Life International believes that chlorination alone is sufficient for many applications. LEAMIS International Ministries, however, likes to combine the McGuire unit with a rock and bio-sand filtration system, to remove larger parasites.

LEAMIS has installed several of these systems, primarily in Kenya, and when LEAMIS co-founder Debra Snellen began talking to representatives of a church in Cochabamba, they told her that they, too, were interested in the water purification system. LEAMIS had a partner who had committed to pay the cost of a future water purification system for one of its projects, and so began making plans to bring the system to Bolivia. Debra asked me to head up the project, and even though I hadn't worked directly with the system on any of my previous LEAMIS trips I was trained in its use by LEAMIS associates Bob Willems and Frank Schroer. I worried about the project, however, because I'm not particularly handy. I hoped that I would be able to work with our host church to get the system installed and up and running.

When Debra and I arrived in Cochabamba, we discovered that the site for our various training workshops -- a school in Villa Candelaria, a poor neighborhood on the outskirts of Cochabamba -- wasn't quite what we were expecting. It was in the city and was already hooked up to some sort of municipal water system. The water system was not too reliable; I had to do without a shower several times during the trip because the water system wasn't working that morning. Rudolf Band and Ronald Trujillo, two officials of the non-profit group which operates the school, said the water wasn't the best of quality and sometimes became contaminated by the time it got to the tap.

But when we explained our filtration and chlorination system, Rudolf and Ronald weren't as receptive as we had assumed from their original interest. They thought the filtration system would take up too much room. They also thought the quantities of water which the system would produce were more than they needed or could use. Debra told them that the children in the school needed to drink more water and that excess purified water could be sold or given away, at the school's discretion, to others in the area.

Because the church members said they couldn't find clean 50-gallon drums suitable for filtering and holding drinking water, four of these 450-liter water tanks were purchased. Many homes in Villa Candelaria have this type of tank sitting on their rooftops. (T-G Photo by John I. Carney) [Click to enlarge]

Rudolf and Ronald also said that it would be difficult to find clean plastic drums of the type LEAMIS typically uses for the filtration system. Many homes in Villa Candelaria have short, squat black water tanks sitting on their roofs, a way of storing water to compensate for outages. It was suggested that we look at buying water tanks for the filtration system instead of plastic drums. Ronald and Rudolf insisted that the water tanks might be too expensive, but when we priced them, Debra said that the cost of the tanks was within what LEAMIS had budgeted for the project, so the school would not have to worry about paying for them.

We bought the water tanks in Cochabamba and made some preliminary inquiries about the cost and availability of sand and rock. We also demonstrated the operation of the McGuire unit, although I probably looked like an idiot stumbling around with it. But Ronald and Rudolf continued to drag their feet. Was there any way to skip the filtration process, or use fewer tanks? They seemed to have no real desire to install the unit which LEAMIS had purchased and brought thousands of miles to Bolivia.

By Thursday of our work week in Villa Candelaria, Debra and I had just about given up on the project. To make things even more frustrating, a change in our schedule meant that we were scheduled to do little or nothing during the day Thursday or Friday, which would have been a perfect time to work on the system.

But when Gaston Saavedra, Rudolf's uncle and one of the pastors of our host church, got back into town, everything changed. Gaston had been on a trip with youth from the church in Cochabamba; he and the teens were delayed in their return due to a miner's strike which resulted in a highway blockade.

When Gast--n returned, however, he and Debra discussed the water project and its importance, and he determined that we would work on it Monday, before Debra and I left town for Santa Cruz. There was not enough time left to actually build the filtration system, but we could make sure that there were two people at the school who had been fully trained in operating the chlorinator. We would leave behind the drawings, instructions and connectors necessary to build the filter system. At the bare minimum, they could use the chlorinator without filtration.

Monday morning came. Ronald was chosen as one of the two who would be put through their paces on the operating system; the other would be Freddy Mamani, at whose home I stayed while in Cochabamba.

I walked through the process once myself, just as I had the previous week. Then, Debra and I emptied out the unit and told Freddy and Ronald to set it up without our help.

They made good progress, but when we went to actually chlorinate the water something wasn't working quite right. We finally determined that the submersible pump was the culprit. It was making a strange noise and didn't seem to be pumping as it should. I took it apart to see if I could find a problem but there was nothing visible. The pump was clearly not functioning correctly, and so Debra decided that we would take the pump back to the U.S. and send either the repaired pump or a new one back to Cochabamba.

In practical terms, we had walked Ronald and Freddy through all of the important parts of the process. But I still felt like that part of my mission was incomplete, if only because they hadn't been able to complete the operation by themselves.

TOMORROW: A tale of two birthday parties