David Schneider from Spectrum.ieee.org shows us how to watch over your water usage using an Arduino and a Raspberry Pi. He writes:
California, where I once lived, is in the midst of a severe drought. Thankfully, I now reside in North Carolina, a much wetter state. But even here there have been years when water was in short supply and people were asked to conserve.
My system doesn’t require plumbing alterations, and it transmits the information via my home wireless network, so I can view water use on a connected device anywhere in the house. Now when my teenage kids take profligate showers, I can berate them with quantitative measurements!
To measure water flowing from the municipal supply, I employed a digital compass—that is, a 2-axis magnetometer—that I originally purchased some time ago from SparkFun Electronics to use as a direction finder. SparkFun no longer sells that module, but for even less money (US $15), you can now purchase a 3-axis magnetometer, which I suspect would work just as well or even better.
Build a Wireless Water Meter for Your Home – [Link]