🔍 BRIEF INTRODUCTION
Water is a vital resource, and efficient management of water storage is essential, especially in residential, agricultural, and industrial settings. Traditionally, monitoring the water level in storage tanks is done manually, which can be time-consuming, inaccurate, and prone to human error. The Smart Water Tank System addresses this challenge by providing an automated solution for monitoring and controlling the water level in a tank.
This system is built using an Arduino Uno microcontroller, an ultrasonic sensor (HC-SR04) to measure water level, an LCD with I2C interface to display the level and status, and a relay module to control a water pump. The ultrasonic sensor continuously monitors the water level, and the Arduino processes this data to determine whether the pump should be turned ON or OFF. The LCD display provides real-time updates, such as the current water level percentage and pump status.
By automating the filling process and preventing both overflows and dry conditions, the Smart Water Tank system offers a reliable, low-cost, and energy-efficient solution for water management.
📋COMPONENTS LIST
S.No |
Component |
Specification/Details |
Quantity |
1 |
Arduino Uno |
Microcontroller board |
1 |
2 |
Ultrasonic Sensor (HC-SR04) |
Range: 2cm – 400cm, for level measurement |
1 |
3 |
LCD Display (16x2) with I2C |
I2C module reduces wiring |
1 |
4 |
Relay Module |
1-channel (5V), for switching the pump |
1 |
5 |
Water Pump |
DC or AC pump (depending on use) |
1 |
6 |
Power Supply |
5V/9V/12V for Arduino and pump (as needed) |
1 |
7 |
Jumper Wires |
Male-to-Male and Male-to-Female |
As required |
8 |
Breadboard (optional) |
For prototyping |
1 |
9 |
Resistors (optional) |
For signal conditioning (if needed) |
As required |
10 |
Tank or container |
Simulated or real water tank |
1 |
11 |
Diode (e.g., 1N4007) |
Flyback diode for pump relay protection |
1 |
12 |
Transistor (e.g., BC547 or TIP122) |
For switching (if relay module requires) |
1 (if needed) |
BLOCK DIAGRAM

WORKING
The Smart Water Tank System is designed to automatically monitor the water level inside a tank and control the water pump accordingly to maintain optimal levels. It operates based on real-time distance measurement using an ultrasonic sensor and executes logic through the Arduino Uno microcontroller.
🧩 Step-by-Step Working Process:
-
Distance Measurement Using Ultrasonic Sensor:
-
The HC-SR04 ultrasonic sensor is mounted at the top of the water tank.
-
It emits ultrasonic pulses (triggered by Arduino) and listens for the echo reflected from the water surface.
-
The time taken for the echo to return is used to calculate the distance between the sensor and the water surface using the formula:
Distance=Time×Speed of Sound2\text{Distance} = \frac{\text{Time} \times \text{Speed of Sound}}{2}Distance=2Time×Speed of Sound
-
This distance is subtracted from the total tank height to get the current water level.
-
Level Calculation and Percentage Conversion:
-
The measured water level (in cm) is converted into a percentage relative to the total tank height.
-
This allows easy threshold setting (e.g., turn on the pump if water is below 30%).
-
LCD Display Output:
-
Pump Control via Relay:
-
The Arduino checks the current water level percentage.
-
If the level is below 30%, the Arduino activates the relay, turning ON the pump.
-
If the water level reaches or exceeds 95%, the relay is deactivated, turning the pump OFF.
-
The relay acts as a switch, allowing the low-power Arduino to safely control the high-power water pump.
-
Looping Functionality:
IMAGES ARE ONLY FOR SAMPLE PURPOSES!!!!!!