If you're looking for ways to use less water, Instructables user tamberg developed a DIY water faucet sensor that shows you when you've used up a liter. Using an Arduino, flow sensor, and colored ...

This sensor contains a nine-axis inertial measurement unit (IMU) that detects how far you’ve twisted, turned or tilted the handle, and uses that information to estimate the amount of water flow.

Flume’s Home Water Protection Service provides 24/7 water flow monitoring across an entire home and property, utilizing Wi-Fi connectivity and a sensor easily connected to the existing water meter.

“The sensors monitor the level, flow and pressure of the streams and allow the council to quickly put outalerts on rising water levels, allowing people to be prepared during weather events.