Wireless Battery Operated Water Tank Overflow Transmitter

In India and worldwide water, availability is a huge issue so saving water is most important work these days for the environment. As like most of the Indian families using water tank to store water and use them later. The main issue is that wastage of water once water tank got filled and most of the water tank fixed on the rooftop. There are lots of devices available in the market to warn overflow tank but most of comes with bulky wires and connection to show the water level or water overflow warning.

But I want to make a simple battery operate design/circuit for a water tank that transmits water overflow signal every 8 or 10 seconds to the receiver. For the signal receiver, there is no issue of power but for transmitter power, an important factor and this is must that transmitter circuit works on battery for a long time.

So Here I want to design a circuit works on battery (3v to 5v). A circuit with two wire fix at the top of the water tank or on the sidewall and circuit check wires connection for water touch them every 8 to 10 sec. If water touched the wire transmitter release a signal (go to sleep mode again for next 10 sec) to the receiver and receiver worn by a small buzzer for 10 sec. Again after 10 sec transmitter check the water level and release a signal to the receiver. Similar water tank alarms comes costly around 90$ to 150$. I want to use AtTiny85 or min Arduino, Wireless module 433mhz to save money. So please help me start this project by programming or another way to finalize this project and help me save water.

Good project!

First make a wired version as a proof you can actually measure the water level reliably.
If that works focus on making it wireless.

A question, what do you do when a tank is 100% full and it will start to overflow?
What are the actions then?
Do you want to pump the water to the neighbours tank? (risk of cross contamination forbids)
Start doing the laundry?
Open a faucet to reduce the level?

Imho I think it is a bigger problem when the tank is nearly empty and the water must be spared /rationed.
Should that be included?

Perhaps the simplest way would be to use a float switch which turns on a transmitter.

The choice of transmitter depends on the range you need. 433MHz tx/rx modules are cheap and freely available as eg car remotes.

Allan

Carefully study Nick Gammon's excellent tutorial on a solar powered Arduino remote sensor. It has everything you need.