Robustness of IoT-connected e-Taps for sustainable service delivery of rural water supply

‘e-Taps’ monitor flow at rural water points in sub-Saharan Africa and enhance revenue collection using pre-paid tags. Real-time, high temporal resolution e-Tap usage data are available to service providers. In this paper, the robustness of the e-Tap is evaluated in the laboratory regarding (1) accuracy of the flow meter and (2) the flow rate reduction caused by addition of a y-strainer and debris build-up. An average relative error of +3.63% across varying flow rates is found. A general calibration will bring 95.45% of measurements within a ±4.54% error range. In the y-strainer, smaller gauze sizes, smaller debris sizes, and higher debris loads cause greater flow rate reductions. The maximum reduction observed was only approximately 68% of the baseline flow rate. These physical findings can be integrated into software solutions to management problems.