Microphone, Audio Processing and Arduino

Hi guys, I would greatly appreciate your help, I have a different background than electronics and programming, so I am completely lost and in desperately need of help, so any little help can save me. I want to do a project to for saving water in the shower to one of my university courses. The idea is to have a motion sensor and a microphone connected to and Arduino Uno, so when the sensor sense movement in the shower (when the person gets in) and when the mic “senses” the shower noise activates a timer. What I want to do next is just give a sound signal when a time is reached. For now I just want to know if the microphone part is possible, I have seen some projects that detects sound, but I don’t know if an specific sound like the shower noise can be detected, Also I am not sure which microphone will be best for this, I read and I will probably need and Electrec plus an amplifier, but honestly I don’t know this topic, so I am not sure, If there is someone that knows if this is possible and how it can be possible it will be great and as I said lifesaver, thanks a lot and excuse my huge ignorance.

Detecting a specific sound (running shower water versus someone singing or shower curtain movement) would require sophisticated audio processing. A simpler method might be a pressure sensor in the line between the shower valve and the shower head. Pressure will rise when the shower valve is opened.

yes, I wanted to detect the specific sound of the water running. I thought that may be difficult, my research confirmed it and now you too, thanks for the advice, that is really helpful, I may go this way. Thanks a lot