Annual rain and flood had causes many cases of cars trapped in road tunnels in Malaysia. Hence, the prototype design is aim to solve this problem. It is a product which can sense water level and gives alert base on the height of the flood detected. Alert method included SMS to related authority, siren and a illuminated danger sign board to be equipped at the entrance of a tunnel. Live data if feed in a website to display info on the temperature, humidity and water level which can be view by an authority governing certain road tunnel safety.