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This fall, Alexandra joined the Low Flow Stacked Rapid Sand Filter team and the 4" 10 cm filter sub-team. She and her teammate, Jeanette, have constructed a manometer to test tested the backwash initiator on the existing filter. To date, we have attached the manometer to the filter and are constructing a way to quantify the effects of the backwash initiatorto see if it can initiate backwash at a constant head of 1.4 meters. They found that the backwash initiator is actually more of a backwash indicator, as they could not rotate it and initiate backwash unless the sand bed was already fluidized. They also constructed a new sand drain for the current 10 cm test filter.