Main menu


Water Alarm: Keep Your Pool, Pond, or Tank at the Perfect Level


Water Alarm: Keep Your Pool, Pond, or Tank at the Perfect Level

Water Alarm
Water Alarm

How many times have you discovered your pool, pond, or fish tank running dry because it was hard to tell how low the water level was? An easy way to avoid this problem and keep your water level at the perfect place is with Water Alarm, a simple circuit that will turn on when the water level drops below a certain point. This can help you keep an eye on pools, ponds, irrigation systems, fish tanks, and more!

How Does it Work?

The Water Alarm is a simple circuit that uses a float switch to detect when the water level is below a certain point. When the water level drops, the float switch activates and triggers the alarm. The alarm can be an audible sound, a light, or both. You can also use the Water Alarm to shut off a pump or other equipment when the water level gets too low. In this case, you would connect the pump to one of the terminals on the switch. 

For example, if you want your pump to turn on when the water level reaches 10 inches, then connect it between terminals 1 and 2. To have the pump turn off when the water level reaches 20 inches, connect it between terminals 3 and 4. If you just want an alarm without turning anything on or off, leave the pump disconnected from any terminals.

Parts Needed and Where to Buy Them

You'll need a water sensor, an LED, and a 9V battery. You can find all of these parts at your local electronics store. Water sensors are usually located in gardening supplies. Simply mount the water sensor to any surface near where you want to measure the water level. Then connect one end of the wire from the sensor to the positive terminal on the LED, and then connect another wire from the negative terminal on the LED to the ground (negative). Now when there is enough water below this threshold level, it will turn on! When the water gets high enough, it turns off. It's easy to use and inexpensive! 

In addition, it doesn't require a lot of electricity so no worries about getting stuck with expensive electric bills. Another great benefit is that it has a nice loud alarm sound that lets you know when the water is too low! And finally, if you're not sure what size sensor to buy, this circuit should work for most types of sensors.

Fritzing Breadboard Diagram

Fritzing is an open-source hardware initiative that makes electronics accessible as a creative material for anyone. The Fritzing application is used by designers, artists, educators, and hobbyists to develop interactive electronics prototypes. For this project, you will use the Fritzing Breadboard Diagram page. Click on the breadboard icon to start a new breadboard diagram. Name your circuit Water Alarm in the bottom left corner of the window, then click Create. 

Double-click on each component in turn and place it on your breadboard according to its placement guide in order to build your circuit. When you have finished, connect two jumper wires from pins 2 and 3 (relay) to pins 9 and 10 (push button). Connect one more jumper wire from pin 6 (LED) to pin 11 (positive rail). Connect another jumper wire from pin 1 (negative rail) to the negative terminal of your battery. 

Now attach the long end of your buzzer to the positive terminal and the short end to the ground. To test if your circuit works, press the push button and make sure the LED lights up. If not, double-check all connections again! You are now ready to create an enclosure with your choice of materials using one sheet of cereal box cardboard (or any other kind) which can be cut with scissors or a utility knife.

Circuit Schematic

The Water Alarm is a simple circuit that uses a 555 timer chip. The chip is configured as an astable multivibrator. That means it will oscillate between two states: high and low. When the water level drops below a certain point, the circuit will change state and turn on an LED. It also has a piezo buzzer which produces an irritating noise to alert you of this event. 

To avoid false alarms from rain or other moisture, there are three holes in the top of the container for wire leads. These wires go to some type of sensor that detects when water levels are above normal levels (e.g., a photocell). If so, the alarm will be disabled until those conditions change again.

The unit can also be mounted outdoors with a plastic container attached to the case lid. I used JB Weld epoxy glue to attach my lid to my plastic bucket but any good adhesive should work just fine. You'll need to use a drill bit slightly smaller than your screws to make holes where you want the screws to go. 

Use washers on both sides of the screws and tighten them down tight with your hands then tighten them down more with a screwdriver if necessary. Finally, add silicone caulk around all four edges of the base of your container to seal out water leaks. Now set up your water sensors using one hole each.

Final Words

A water alarm is a great way to keep your pool, pond, or tank at the perfect level. By monitoring the water level, you can be sure that your pump is working properly and that your fish are healthy. Plus, if the water level gets too low, the alarm will sound and alert you to take action. 

The design of this project was simple, but it is an effective way to keep an eye on things. So next time you’re away from home and wondering how much water there is in your swimming pool or pond, give this project a try! It's easy to set up and use and won't cost you anything more than some copper wire, a few resistors, and some LEDs. 

For more information about electronics projects for beginners, visit our website for other helpful posts like The Simplest Way To Measure Time or Useful Ideas for Circuit Building. We also provide links to some free circuit-building software so you can get started right away with designing circuits. 

You might want to start with Project 1-10 - LED Circuit Builder Kit - Biscuit Boards Arduino Project Kit because it includes everything you need except for a battery pack. And don't forget to follow us on Facebook, Twitter, and Google+ for even more helpful tutorials and cool designs.


table of contents title