IoT Water Quality Monitor

IoT Water Quality Monitor

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How It Works

• A pH sensor probe reports acidity/alkalinity as an analog voltage, calibrated against known buffer solutions.
• A turbidity sensor measures water clarity by detecting how much light scatters through the sample.
• An ESP8266/ESP32 reads both sensors and uploads readings to a cloud IoT platform at a set interval.
• When pH or turbidity crosses a preset safe-range threshold, the system triggers an alert — local buzzer and/or a cloud-platform notification — flagging the reading for follow-up.

Components

ESP8266 or ESP32
pH sensor probe + interface module
Turbidity sensor
IoT platform (ThingSpeak/Blynk)
Waterproof enclosure for sensor probes

Applications

• Drinking water source monitoring
• Aquaculture and fish-farming water quality checks
• Industrial wastewater/effluent monitoring

Advantages

• Continuous monitoring catches quality drift earlier than periodic manual testing
• Cloud alerts flag unsafe readings automatically, without someone checking a log
• Extendable to more parameters (TDS, dissolved oxygen) using the same architecture

Sample Code — pH and Turbidity Threshold Alerting

// Simplified water quality monitoring - ESP8266
int phSensorPin = A0;
int turbiditySensorPin = A1;
float safePhLow = 6.5, safePhHigh = 8.5;
int turbidityThreshold = 400;

void setup() {
  Serial.begin(9600);
}

void loop() {
  float ph = readPH(phSensorPin);         // calibrated conversion
  int turbidity = analogRead(turbiditySensorPin);

  if (ph < safePhLow || ph > safePhHigh) {
    Serial.println("ALERT: pH out of safe range");
  }
  if (turbidity > turbidityThreshold) {
    Serial.println("ALERT: high turbidity detected");
  }
  // uploadToCloud(ph, turbidity); // ThingSpeak/Blynk call
  delay(30000);
}

Related Research

• IoT-Based System for Real-Time Water Quality Monitoring and Advanced Turbidity and pH Sensor Calibration — MDPI IoT