Arduino Based Water Level indicator for underground tank

Projects General Guidance
7

code for ultra sonic sensors can easily be found on google, you just need the model of sensor you're using.

this is for HC-SR04

  digitalWrite(trig,LOW);      // activate Ping sensor 
  delayMicroseconds(5);
  digitalWrite(trig,HIGH);
  delayMicroseconds(10);
  digitalWrite(trig,LOW);
  
  duration = pulseIn(echo,HIGH); //read trig

  cm = (duration / 2) / 29.1; // distance calculation