11 October 2009: Flow Rate Testing
EWB@WSU conducted flow-rate testing on a hand pump designed by a non-profit group, Developing World Technologies. The pump was originally designed as part of a WSU senior design project. The four students who worked on that project started up DWT and continue to refine their pump design. When fully refined, these pumps will be used in Malawi to move drinking water and for irrigation.
A group of EWB@WSU members worked with Dr. Howard Davis to carry out the testing. Those present included:

1. David McDonald, Project Leader
2. Bryan Young
3. Rory Beckstrom
4. Melissa Bogert
5. Said Abdi-dhaharand
6. Ezra Griffey

The testing procedure included pumping 5 gallons of water at 10, 20, and 30 foot heads. Three people were to rotate through each head moving 5 gallons twice at each head. Yet during testing on the 10 foot head, a manufacturing flaw was identified in the pump's one-way valves. The soft rubber flap sealing each one way valve was found to deform under the back pressure. As it deformed, it allowed the water to pass downhill through the pump. The pump’s malfunction was attempted to be remedied on site, but further tests were shown to equally deform the pump valve. Before valve deformation became a problem, the pump moved roughly 10 gallons of water per minute with minimal exertion at a 10 foot head. With moderate exertion, it moved roughly 20 gallons per minute also at a 10 foot head.
Dr. Howard Johnson has contacted the president of Developing World Technologies, Angel Hall, to determine a solution to the valve problem. Testing will resume on that pump when the valve is fixed.