The answer to 'water line rusty water' is that rusty water is often caused by corroded or deteriorating water pipes. This can happen over time as pipes age and rust builds up on the inside, causing discolored, metallic-tasting water.
Some common causes include old galvanized steel pipes, copper pipes with mineral buildup, or even well water with high iron content. Symptoms include reddish-brown, orange, or yellow water coming from your taps. While this is usually not a health hazard, it can stain laundry and damage appliances over time.