2022 Hackaday Prize: Sensible Flow Helps You Keep Track Of Your Water Usage

An infographic showing a tap with a sensor and a flow meter display

Safe, clean drinking water is a scarce resource that shouldn’t be wasted. But it’s not always easy to see how much you’re using when you turn on the tap: is it one liter a minute? Is it ten? How much do you actually use when washing your hands or brushing your teeth? If you’d like to get some hard data on your water usage, have a look at [Josh EJ]’s Sensible Flow project. It contains designs for a set of sensors that measure your water consumption and a convenient little display that shows the total amount consumed.

The most obvious way of measuring water consumption is to install an off-the-shelf flow meter onto your pipe, which is something that Sensible Flow supports. But probably the most interesting part of the project is a design for a non-invasive flow sensor that you can simply attach to any type of tap. 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. You will need to perform an initial calibration step using a timer and measuring cup, but you won’t have to rip open your plumbing just to keep track of your water usage.

Both types of sensors are powered by a coin cell battery that is estimated to work for about one year, thanks to a power-efficient Arduino Pro Mini and a BlueTooth Low Energy (BLE) module to communicate with the base station. The base station plugs into a wall socket and shows the total water consumption on a small one-inch OLED display. STL files for the enclosures are available on the project page, along with detailed circuit diagrams that show how all the parts are connected.

We’ve seen several water flow measurement systems for home use, such as this neat ESP8266-based shower water monitor. If you prefer just a simple visual reminder to turn off the tap, have a look at this LED gadget.

15 thoughts on “2022 Hackaday Prize: Sensible Flow Helps You Keep Track Of Your Water Usage

      1. Except the accuracy of the faucet “meters” is next to worthless, and from flow rate / time of day you can probably figure out where the water was used anyway. It and also doesn’t account for the biggest consumers of water in almost any household: the bathtub/shower, washing machine, and irrigation. Nor does it account for leaks.

        These faucet “meters” would only be useful in *addition* to total consumption monitoring.

  1. I like the idea but the sensors used seem to be an odd fit. A flow sensor for the actual water is way more accurate, can be added to any faucet, and possibly even self-powered.

  2. I wonder how frequently RF water meters update? In my city the water utility company not only installed remotely readable meters, but shows you usage on their website. I don’t think there’s a formal API though, but there’s always SDR…

    Though that might not give the user the kind of feedback they need to make better decisions. Even if the mains meter was low latency and reported frequently, it wouldn’t be able to measure the water used at a single tap.

  3. I have a 3/4 copper line running from my incoming water meter to my house. Why not slip a 3/4 water flow sensor (turbine) and use an ESP32 to count the pulses? The ESP can handle up to 13 microseconds between pulses … way faster than the pulses from the hall effect turbine. Then I would know the water usage for my WHOLE house. But Josh is thinking outside the box … gotta give him kudos for that. What he built could be used for other things. Measuring deflection on some mechanical structure?

    1. The Point of Sensible Flow was to give you a rough estimate of water usage, it would be very easy to setup as it is non-invasive. It can be setup in all kinds of taps including showers/ bathtubs.

      But think long the lines of the step trackers on our smartphones, each application and device shows a different step count. Once you reach the target it gives you a notification to motivate you. The point of Sensible flow was to incentivize you to reduce water consumption rather than providing the most accurate value.

      Sensible flow can also be connected to flow rate sensors, this gives you the possibility to connect to any pipe (including irrigation, washing machine etc) and have very good accuracy. The Base unit displays the real time water usage.

  4. A lot of water softeners have a built in flow meter, generally a small plastic turbine with a magnet sitting inside a plastic pipe and a hall effect or Reed switch counting the revolutions. A local softener supplier might have defective units you could cannibalize.

  5. Better to have faucets that serve their task without Victorian age legacy. The spray faucet here is a good start. Covid and such will teach us not to have handles on hand washing sinks, it should be code now. A hundred years ago we should have had foot operated faucets, now we have hands free faucets. Instead then we were filling stoppered basins and leaving bar-soap residue on our hands. Some germs can grow on a bar of soap.

    People will conserve when the devices enable us. Nobody wants to be given 3 sheets of TP etc.

Leave a Reply

Please be kind and respectful to help make the comments section excellent. (Comment Policy)

This site uses Akismet to reduce spam. Learn how your comment data is processed.