50-foot dead end return line: bacteria risk?

[pas]

Hey everyone,

We recently had our house remodeled and we went tankless. We had the plumber run a (copper) line back to the water heater for a recirculation system, but ultimately we stopped working with the plumber and never installed the recirculation pump.

Currently, the line just terminates with a cap after about 50 feet. Is this a health risk? Do we need to worry about bacterial growth (e.g., legionella) in that pipe? If so, how urgently should we finish this project?

Thanks!

 

[Kreemoweet]

There are countless millions of home water supply systems that contain dead ends of all sorts, and seldom- or never-used fixtures. Yet there is no epidemic
of legionella infection. Virtually all of the sources of advice to homeowners to eliminate such things also stand to profit (individually or collectively)
from that advice being followed. It's just another scare industry. You can put a valve on the end of the run, and flush it periodically, if it makes you feel better.