This is an instructible on how to crudely detect water flow in a pipe and drive an ambient display. I am using a piezo transducer, some LED's and an arduino. The device is a rough prototype of what will eventually become a persuasive technology that motivates sustainable behavior and raises awareness about water use.
This is a project by Stacey Kuznetsov and Eric Paulos at the Living Environments Lab, at Carnegie Mellon University Human Computer Interaction Institute.
Living Environments Lab
The video below illustrates a previous version of this project, where a microphone is used instead of a piezo element to detect water flow. You will achieve better performance when using a piezo transducer, so this instructible details the piezo approach.
Special thanks to Briam Lim, Bryan Pendleton, Chris Harrison and Stuart Anderson for help with ideas and design of this project!