The answer to 'why is my sewer line rusty water' is that a rusty sewer line is often caused by corrosion of the pipes over time. This can happen due to age, chemical buildup, or high mineral content in the water. Symptoms include reddish-brown water coming from drains and fixtures, a metallic taste or smell, and potential clogs or backups.
In many cases, a rusty sewer line will need to be repaired or replaced by a professional plumber. Trying to fix it yourself could be dangerous and may not address the root cause. A plumber can inspect the line, determine the extent of the damage, and recommend the best solution - whether that's cleaning, relining, or fully replacing the pipe.