Disinfecting plumbing after abandoning well

[MrFloratam]

Converting from well to city water. Well has a high total coliform count (no e.coli detected) and the owner wants to switch to city water. Well will be kept for outdoor irrigation only. I understand that there is bacteria in the piping throughout the house. This would be easy to address if we stayed on well water (shock the well, run all taps till bleach smell, let sit 24 hours, flush), but how would I accomplish this once it's connected to city water? Will the city water chlorine content take care of this automatically? Or do I need to "shock" the plumbing after city water has been connected?

If I need to do this myself, I'm thinking of isolating the plumbing and using a 5 gallon bucket with proper bleach mixture and a small electric pump to supply all the lines with the bleach solution. Open all the taps till bleach smell, let sit, then flush, then reconnect city water. Am I overthinking this?

 

[Valveman]

Check the chlorine residual. If it is still strong coming out the faucets I would think that would do the trick.

 

[Sponsor]

 

[Reach4]

For low range testing, LAMOTTE 2963LR-G .25 ppm looks good to me. https://www.globaltestsupply.com/pr...g-total-chlorine-lr-single-factor-test-strips

I have not used such strips.

 

[oldVermonter]

I agree with Valveman. One thing to keep in mind, no new coliform will be introduced once city water is connected, and (even without the chlorine) is dying off pretty quickly. Any chlorine residual will accelerate the die-off rate dramatically (which is why the residual is there).

Even so, I would certainly recommend flushing the pipes very thoroughly with city water before drinking it. Drinking bottled water for a day or so might be overkill...but wouldn't hurt. I wouldn't worry about cooking, bathing etc.

One caveat: the above only applies if the well water is sediment-free. If there is any visible cloudiness, that means there is sediment in the house plumbing. It's a lot harder for chlorine to kill bacteria embedded in sediment pores. In that case, something more drastic might be appropriate.