Wow, I’ve lived this exact chaos! One evening, my nephew “helped” flush, and the toilet decided it was auditioning for Niagara Falls—water everywhere. My spouse and I were running around like crazy, checking under sinks, peeking at the meter outside, totally lost on where the main shutoff was. After that, I realized we needed a proper guide before our house turned into a water park again. I found this really clear step-by-step walkthrough: main water valve location guide . Followed it, labeled the valve, and now I sleep easy knowing we can stop a flood in seconds!