See Corresponding Project Theses and Reports

The Mae La Temporary Shelter in Thailand houses approximately 50,000 refugees of the Karen tribe from Myanmar (Burma).  Mae La has existed for over twenty years and has an improved water system operated by Aide Médical Internationale (AMI).  Drinking water is drawn from a nearby river and from springs, is chlorinated in most cases, and released into a pipe network. Drinking water reaches the population through public tap stands after passing through collection systems, pump stations, storage tanks and distribution networks. An MIT Master of Engineering (MEng)  project team evaluated drinking-water treatment and the water distribution system.
Navid Rahimi focused on the modeling and mapping of the water-distribution system. His work was motivated by the need to develop analysis tools to identify areas of improvements and provide a further understanding of the complexities of the system. AMI is currently planning an expansion in the geographical coverage of the water system, and a modeling tool can provide predictions of the performance of the system when new taps are added. Navid developed and calibrated a model and then used the model to evaluate a variety of system improvement alternatives.  He found that new tap stands could be successful in providing water to underserved areas without adversely affecting system performance elsewhere.

Mary Harding used a geographic information system (GIS) in coordination with Navid’s computer model to better understand the condition of water supply within the Mae La camp. Overall GIS analysis shows that the vast majority of residents in Mae La have sufficient access to water. Homes located further than 115 meters from a tap stand, located further than 180 meters from a rope-pump well, or having access to less than 50 liters of water per day were considered a cause for concern. Approximately one in four homes met these criteria. However, only 5% of homes are located more than 115 meters from a tap stand and 40% of these are in a region of the camp with plentiful access to private springs. Approximately 14% of homes did not meet the rope-pump proximity criterion, and 15% of homes did not meet the available volume criterion.
Katherine (Kat) Vater evaluated alternatives for treating seasonally turbid spring water that is an important water source for Mae La.  Half the drinking water for the camp is provided by thirteen springs.  The volume and turbidity of these springs varies annually, correlating with the rainy and dry seasons.  Treating the varying turbidity and volume at these sources so that the water can be effectively disinfected is the treatment goal.  Horizontal-flow roughing filtration was determined to be an appropriate alternative and a design with two equivalent filters operating in parallel was developed.  One important feature of the filters is baffles that dictate the flow path of water through the filter.  A second feature is an outflow at the top of the filter that will maintain a constant water volume in the filter.  The design was based in part on flow tests and turbidity measurements taken on site.