Water Quality and Usage Monitoring Device

Check your tank with care


How It Works

Team Members

Components and Technology

Advisors and Mentors

Work Done So Far



Water mismanagement and consumption of poluted water is a major challenge, the world is facing currently. Current market is yet to address this issue with an effective solution. The solutions that are currently present on the market are either too expensive for domestic usage or does not meet the user expectations.


To overcome these issues, we are propossing a device which can be used to measure the water quality of the inlet of a water tank and the water level inside the tank. We expect to target both domestic user requirments and industrial user requirements by a reasonable price (click here for budget) User can access to the data using a mobile application.

Water level Monitoring

By using an ultrasonic sensor, water level will be monitored and when the tank is nearing to finish filling, user will be notified. We use ultrasonic sensor because of it's high accuaracy and sensor is not easily effected by water. Also this will generate the usage reports of the water and allow user to observe the current water level in the tank if needed. This measurement also allows to rationing of water and user will be warned in case of overusage.

Water Quality Monitoring

TDS count – by electric conductivity of water

The presence of dissolved solids in water may affect its taste.The palatability of drinking- water has been rated by panels of tasters in relation to its TDS level as follows:

  • excellent, less than 300 mg/litre;
  • good, between 300 and 600 mg/litre;
  • fair, between 600 and 900 mg/litre;
  • poor, between 900 and 1200 mg/litre;
  • unacceptable, greater than 1200 mg/litre
  • Water with extremely low concentrations of TDS may also be unacceptable because of its flat, insipid taste. Click here for see WHO guidelines for drinking water quality

    Turbidity – by measuring scattering of light in water

    Turbidity, which is caused by suspended chemical and biological particles, can have both water safety and aesthetic implications for drinking-water supplies. Turbidity itself does not always represent a direct risk to public health; however, it can indicate the presence of pathogenic microorganisms and be an effective indicator of hazardous events throughout the water supply system, from catchment to point of use. For example, high turbidity in source waters can harbour microbial pathogens, which can be attached to particles and impair disinfection; high turbidity in filtered water can indicate poor removal of pathogens; and an increase in turbidity in distribution systems can indicate sloughing of biofilms and oxide scales or ingress of contaminants through faults such as mains breaks.WHO says that for dinkable water turbidity must be below 5NTU and should be low as possible like 0.1NTU Click here to download the review done on the turbidity by WHO.

    For these 2 measurments, TDS sensors and Turbidity sensors will be used and their readings will be analyzed with ideal water quality levels and determine the water quality of the incoming water to the tank during a filling and notify the user if there is any contamination in the water. We use these 2 sensors because by using these 2 readings we can determine most of the characteristics of water.

    How It Works

    This diagram shows the overall implementation of the system.There are sensors to get the data, server to handle the clients.The system works as below steps.

    • Sensors reads the data
    • Sends the data to the server
    • Server sends the data to the clients
    According to above steps, firstly sensors read the data. The ultra sonic sensor is situated inside the tank and the turbidity sensor is situated inside the water pipe which uses to fill the tank. The readings from these sensor are sent to the atmega chip and by using a wifi module those readings are sent to the server. From server, relavant data sends to clients accordingly. Client may be a mobile user or pc user. When consider the mobile users, by using the mobile app, clients can check the level of water filled to the tank and also can see the water purity percentage. When consider the pc users, they can log into the website and get the above details. There is an alarm module to function without any internet connection which is helpful when the client has no internet access. And it can be implemented according to the clients' desire. Clients can also get daily usage details via the website.

    Team Members

    Harshana Bandara

    Department of Computer Engineering
    Faculty of Engineering
    University of Peradeniya

    Yasitha Herath

    Department of Computer Engineering
    Faculty of Engineering
    University of Peradeniya

    Thushara Weerasundara

    Department of Computer Engineering
    Faculty of Engineering
    University of Peradeniya

    click on images to visit github pages of the members See more..

    Components and Technology

    HTML , CSS and JS

    HTML is a simple and dominant language to formatting web pages.It supports every browser .HTML Combined with CSS and JS can be used to give client an elegant and yet fast experience


    Flutter is free and open source UI framefork which is able to cross platform developments.The language used in flutter is DART which is optimized for UI development.


    Protocol which allows efficient data distribution with lightweight overhead and with high sclabability Reduce bandwidth consumption so the client can have maximized available bandwidth.


    High scalability and better for cloud services


    Provides the connectivity between the device and server.low cost which reduce the prie of the product and low energy consumption which is essential to a long battery life of the devise.

    Ultasonic Sensor

    Reliable hardware for measuring short distances with a sufficient accuracy


    Dr.Isuru Navinna

    Senior Lecturer

    Dr.Zian Marikkar

    Senior Lecturer

    Work Done So Far

    GUI prototype

    GUI was designed with the aid of figma.
    Click herefor experience the GUI

    Circuit Designs

    Click this link to see more about our Circuit Design

    Hardware Testing and Simulation

    Hardware Components are simulated in Tinkercad. click here to see more

    Our Front End Implementation

    Web Site

    Our web site UI is designed to give a user friendly experience to the customer in a very simple manner. It uses dynamic web pages to interact with users therefore fast responses can be obtained with less data usage.

    Role Based Access

    This offers different user expirience to the user depending on the role of a user.
    3 roles in our system are,

    1. Super Admin - Give access to Admin Users
    2. Admin - Supervise Users (Customers)
    3. User - Customers


    Web Site Views

    1. Customer UI

    Log In

    Daily Usage

    Monthly Usage

    Sign Up

    Getting User Details


    2. Admin UI

    Admin View

    Delete a User

    Update a User


    3. Super Admin UI

    Admin View

    Create Administrative User

    Delete an Admin


    Mobile App

    App with limited access for customers

    App uses validate methods when a user does a login attempt to avoid un-necassary requests to the server

    Login Screen

    Home Screen

    Tank Details

    Invalid email

    Invalid Password

    Tank info

    Tests Conducted

    1. Penetration Testing

    Several Penetration Tests were carried out in order to check vulnerabilities in our backend system. Tools used on those tests are


    Packet Sniffing

    End Point Responses

    Security Headers

    OS information

    Security Headers

    2.Unit and integration Testing

    Unit test are carried out to check the functionality of the seperated functions and integration tests are used to test user creation and roles, to test sensor readings storing and validity.Below tools are used to test these.

    • Mocha
    • Chai




    We implemented our security measures using these results.

    Security Aspects

    Embeded Hardware Designs

    Components List

    Designs made for fabrication

    Embeded System

    Water Quality Monitoring Module

    Water will enter this module and Quality Measurements will be recorded. Readings will be taken as analog inputs.

    Water Usage Monitoring Module

    Water Usage will be recorded using this module. Readings will be taken by external inturrupts in microcontroller chip.

    User Expirience Optimization



    Plan For The Embeded Systems Testing

    There are two parts of our embedded system testing plan.Those parts are showed below.

    Aim is to ensure the reliability of our product by doing these tests.

    Hardware Testing

    In this we do tests when soldering and to test the functionality of the sensor devices.

    When soldering we do below steps,

    1. Soldering and testing the power sections one by one
    2. Solder the relavant wires from the sensors with microcontroller and test the basic functionality
    3. check the connectivity

    To check the connectivity we use oscilloscope or logic analyzers.

    To do the sensor testings for turbidity sensor and TDS count sensor we use glasses with water which desolved with different kind of substances as below.

    By dipping the sensors inside the water glasses we test the functionality of the sensors and how the readings change according to the difference of water. By those readings we can calibrate the sensor readings accordingly. And also we can detect if the sensors are deffected by checking the sensor readings. To test Ultrasonic sensor we can use above glasses with different water levels and do the same tests.

    Node Software Testing

    In this testing we do test to check variable overflows, compiler optimizations and typing mistakes. We use below techniques to do the debugging.

    And also we are planning to check the real time sensor readings are showing on our web site and the app. By this we can make sure that the interaction between node software and backend works correctly.

    Embeded Software Explanation

    This device utilizes the services of Arduino UNO R3 board which has ATMEGA328P U chip and NodeMcu ESP-12E board for WiFi connection. Let's consider the working procedure of the device step by step.

    Device Initialization

    1. When the device is powered up, NodeMCU will creates a WiFi server on port 80 under the url of www.aquawatcher.com using "DNS" and "WebServer" modules. We can connect to that network and set up user details and tank details. Then we can enter our WiFi network details as well. Those details will be stored in EEPROM memory of the device until they are updated. Therefore user won't have to set those values again on reboot.
    2. We can reset the above details by pressing reset button and going through the same procedure as before.
    3. Thereafter, server will be closed down and normal procedure of the device will occur.
    4. Working Procedure

      1. Water Level will be measured using Ultra Sonic sensor using an analog input pin. This will be used to get tank size as well.
      2. Water Usage will be measured using a Flow Meter using external inturrupts.
      3. Water Quality will be measured using TDS and Turbidity Sensors using an analog input pins.
      4. All the above modules will use their own custom libraries.
      5. Readings will be taken periodically.
      6. When the water is contacted with the sensors, device will identify water is filling.
      7. Then the device will start sending new data to the server.
      8. When an issue occurs regarding water level or quality, an alarm will be set off using Tone function.
      9. Water quality standards are preseted values.
      10. Communication between 2 boards will be done using serial communication. Extra pins in NodeMCU board was set as serial pins using Softwareserial library.
      11. Solar panels are intergrated as power source.

      Device Installation

      Water Level Monitor

      1. 1st empty the tank
      2. Then Install the "Water Level Monitor" inside of the closing lid of the tank. Make sure it is levelled

      Water Quality Monitor

      1. 1st remove the inlet of the tank.
      2. Then Install the "Water Quality Monitor" to the inlet and then insert inlet pipe to the back of the device.
      3. Make sure to expose the device to direct sun light if you choose to use our solar panel intergrated version..

      Getting Started

      There are two parts of setting up the device.

      Device Initialization

      1st we need to store user email and tank number in the device. 1st connect the device to the power, then connect with "AquaWatcher device Setup!" wifi network. Then go to the address www.aquawatcher.com and provide information.
      It will be convinient to you if you installed our "AquaWatcher" app on your android/iOS device as well.

      Connecting to WiFi

      Then wifi network "Aqua Watcher" will be available and connect to it. Then go to manage wifi network and enter your wifi network information.

      Start Operation

      Cloud Deployment

      1. A Node.js based server is deployed in an aws ec2 instance.
      2. URL of the website is www.aquawatcher.ml .
      3. 2 webservers are handling requests and they are configured using nginx. Round robin method is utilized.

      4. Admin access is restricted to certain ip addresses and ports to prevent unauthorized requests to admin endpoints.
      5. Database is a MongoDB implementation.
      6. Database access is restricted to unknown ip addresses.
      7. Database takes snapshots of it self to keep backups.

      Future Plans

      1. Water leakage detection functionalities.
      2. Extend the compatibility to other chemical types to install with chemical tanks.
      3. Set automatic valves.
      4. Improve app and server architecture.