Making Effective, Affordable Water Level Monitors

February 12, 2026 by Donald Papp 36 Comments

Water wells are simple things, but that doesn’t mean they are maintenance-free. It can be important to monitor water levels in a well, and that gets complicated when the well is remote. Commercial solutions exist, of course, but tend to be expensive and even impractical in some cases. That’s where [Hans Gaensbauer]’s low-cost, buoyancy-based well monitor comes in. An Engineers Without Border project, it not only cleverly measures water level in a simple way — logging to a text file on a USB stick in the process — but it’s so low-power that a single battery can run it for years.

The steel cable (bottom left) is attached to a submerged length of pipe, and inside the cylinder is a custom load cell. The lower the water level, the higher the apparent weight of the submerged pipe.

The monitor [Hans] designed works in the following way: suspend a length of pipe inside the well, and attach that pipe to a load cell. The apparent weight of the pipe will be directly proportional to how much of the pipe is above water. The fuller the well, the less the pipe will seem to weigh. It’s very clever, requires nothing to be in the well that isn’t already water-safe, and was designed so that the electronics sit outside in a weatherproof enclosure. Cost comes out to about $25 each, which compares pretty favorably to the $1000+ range of industrial sensors.

The concept is clever, but it took more that that to create a workable solution. For one thing, space was an issue. The entire well cap was only six inches in diameter, most of which was already occupied. [Hans] figured he had only about an inch to work with, but he made it work by designing a custom load cell out of a piece of aluminum with four strain gauges bonded to it. The resulting sensor is narrow, and sits within a nylon and PTFE tube that mounts vertically to the top of the well cap. Out from the bottom comes a steel cable that attaches to the submerged tube, and out the top comes a cable that brings the signals to the rest of the electronics in a separate enclosure. More details on the well monitor are in the project’s GitHub repository.

All one has to do after it’s installed is swap out the USB stick to retrieve readings, and every once in a long while change the battery. It sure beats taking manual sensor readings constantly, like meteorologists did back in WWII.

An Over-Engineered Basement Monitor

November 25, 2024 by Lewin Day 10 Comments

[Stephen] has a basement that depends on a sump pump. What that means is if the pump fails or the power goes out, the basement floods—which is rather undesirable. Not wanting to rely on a single point of failure, [Stephen] decided to build a monitor for the basement situation, which quickly spiralled to a greater degree of complexity than he initially expected.

The initial plan was just to have water level sensors reporting data over a modified CATS packet radio transmitter. On the other end, the plan was to capture the feed via a CATS receiver, pipe the data to the internet via FELINET, and then have the data displayed on a Grafana dashboard. Simple enough. From there, though, [Stephen] started musing on the possibilities. He thought about capturing humidity data to verify the dehumidifier was working. Plus, temperature would be handy to get early warning before any pipes were frozen in colder times. Achieving those aims would be easy enough with a BME280 sensor, though hacking it into the CATS rig was a little challenging.

The results are pretty neat, though. [Stephen] can now track all the vital signs of his basement remotely, with all the data displayed elegantly on a nice Grafana dashboard. If you’re looking to get started on a similar project, we’ve featured a great Grafana guide at a previous Supercon, just by the by. All in all, [Stephen’s] project may have a touch of the old overkill, but sometimes, the most rewarding projects are the ones you pour your heart and soul into!

Building The Most High-Tech Pond In The Neighborhood

August 11, 2022 by Tom Nardi 14 Comments

What do you think of when you hear the word pond? If you’re like most people, it conjures up images of a simple water-filled hole in the ground, maybe with a few fish added in for good measure. But not [Anders Johansson] — his pond is a technical marvel, utilizing more unique pieces of hardware and software than many of the more traditional projects that have graced these projects over the years.

In fact, this is one of those projects that is so grand in scope that any summary we publish here simply can’t do it justice. The aptly-named Poseidon project is built up of several modular components, ranging from an automated fish feeder to an array of sensors to monitor the condition of the water itself. How many other ponds can publish their current water level, pH, and oxygen saturation over MQTT?

The ESP8266 fish feeder is just one element of Poseidon

[Anders] has provided schematics, 3D models, and source code for all the various systems built into the pond, but the documentation is where this project really shines. Each module has it’s own detailed write-up, which should provide you with more than enough guidance should you want to recreate or remix what he’s put together. Even if you use only one or two of the modules he’s put together, you’ll still be ahead of the game compared to the chumps who have to maintain their pond the old fashioned way.

In the past we’ve seen projects that tackled some of the individual elements [Anders] has developed, such as 3D printed fish feeders, but after searching through the archives we can’t find anything that’s even half as ambitious as Poseidon. At least, not for ponds. It reminds us more of a highly advanced aquaponics setup, and we wonder if that might not be a possible spin-off of the core project in the future.

Shower Water Monitor Tracks The Dollars And Cents

July 24, 2019 by Lewin Day 27 Comments

There’s nothing quite as relaxing as a long, hot shower. This has the tendency of making the bather absent minded as to the amount of water being used, which can lead to excessive bills. [LiamOSM] built a device to monitor this instead, and calculate the cost, to boot.

The device consists of an Arduino hooked up to a cheap flow meter sourced from Banggood. The sensor consists of a paddle wheel that sits in the water flow, fitted with a magnet. A hall effect sensor picks up pulses as the magnet spins, and counting these allows the flow rate to be measured. An HD44780 LCD screen is used to display the readings, controlled over I²C.

To avoid issues in the bathroom environment, the enclosure was designed to be waterproof. The LCD is mounted behind a clear plastic window sourced from vegetable packaging, and the button chosen was specially selected for its sealing grommets. We’d love to see a proper submersion test, but for the most part, it appears to be doing a good job in the bathroom.

If you’re interested in monitoring your water use as a household, you might find it possible to piggy back on the municipal meter.