The answer to 'water line rusty water' is that rusty water is typically caused by corrosion in the water supply lines. Over time, the metal pipes can rust and release iron particles into the water, giving it a reddish-brown color. This is a common issue, especially in older homes with galvanized steel or cast iron plumbing.
Some common symptoms of rusty water include discolored water, a metallic taste, and staining of sinks, tubs, and laundry. The solutions can range from replacing sections of the pipe to installing a whole-house water filtration system, depending on the severity of the issue.