Oxfam humanitarian response specialist Kenny Rae is currently in Haiti working on the recovery effort. Here’s his latest blog from Port-au-Prince.

Six months ago, Tom Mahin’s focus was figuring out how to improve the quality of drinking water in the Massachusetts city of Gloucester, whose 30,000 residents had been told to boil their tap water before drinking it due to high levels of harmful bacteria.

Today his task, albeit on a smaller scale, is arguably more important: For the first time since the January 12 earthquake, 340 displaced families in Impasse Fouget, Port-au-Prince, have safe drinking water, thanks to Mahin and Haitian engineer Donald St. Preux. Mahin is a drinking water specialist with the Massachusetts Department of Environmental Protection and is working as an advisor to Oxfam America in Haiti.

Because of the urgent need, we chose this spontaneous camp to be the first to receive one of the 10 bladders—they look like big rubber pillows that hold about 2,900 gallons of water—that just arrived. Until now the 1,482 people in this densely populated location close to the city center were venturing out as far as a kilometer for drinking water.

Oxfam’s job is not only to provide water, but to ensure its quality, all with the participation of the people who will be drinking it.

At Impasse Fouget, our first task was to build a large platform with rubble, rocks, and earth on which the bladder could rest. A bladder like this filled with water weighs 10 tons, so the platform has to be well constructed–a task that community members took on, with no request for payment. A flexible pipe running to a set of five outdoor faucets carries the water from bladder down to where people can draw it.

Chlorinating water ensures its safety—and Oxfam works to reinforce that idea through hygiene promotion activities in the camps. When a delivery truck comes to fill the bladder, chlorine is added, a responsibility we have given to local users who have selected a water committee to carry it out. Mahin provides bottles of a one-percent chlorine solution (quite safe—household bleach is six percent) to a committee member who adds it to the bladder. An Oxfam engineer, working with the same handheld meter used by water authorities in the US, monitors the chlorine level to determine whether it’s appropriate, and can adjust the concentration if necessary.

Oxfam is working in camps of many sizes, from a few hundred people to many thousands. Our team’s focus is on 35 smaller encampments in the Delmas district. Between 200 and 2,100 people might reside in each. Working at this scale makes our community-based approach for chlorination effective.

A test of the water emerging from the tank at Impasse Fouget showed an acceptable residual chlorine level of 2 mg/liter–enough to ensure any bugs in the water would be killed, but not enough to be tasted except by the most sensitive palate.

Mahin’s with us for a couple of weeks, and by the time he returns to Boston he will have helped to bring safe water to more than12,000 people—almost half the number who live in Gloucester.