Well Chlorination Frequency Q&A

Someone recommended using a regular "maintenance dose" of bleach in our well every few months

Thank you for your informative shock procedure and your FAQ section!

I have an additional question: is it possible to do a "maintenance dose" of chlorine every month or so, like a cup or pint? We have a bored well, and it showed bacteria again in just a few months.

The water quality office said this is a common occurrence for bored wells, and they mainly recommend chlorinators (which one guy said would be $2000 to install!).

When I asked what people did before chlorinators, is when he mentioned knowing of people who put in maintenance doses of Clorox. But I'd like a 2nd opinion on that. Thanks again! On 2018-05-14 by Chris

by (mod) - A "maintenance dose" of chlorine or bleach into a well won't assure safe drinking water

Chris:

A "maintenance dose" of chlorine or bleach into a well is not a good idea in my opinion.

First: your dose will be too dilute to have any useful effect - if you don't reach sufficient bleach concentration in the water it won't kill bacteria that may be present

Second: repeated bleaching at a functional concentration in the well may lead to corrosion problems in plumbing or health problems for building occupants

If there is a persistent bacterial source that you can't fix - for example if it's in the supplying water table - then you need a permanently installed water disinfection system.

Bottom line: in my OPINION if you test your well water after a few days after disinfecting it and the water is not contaminated with coliform or other bacteria and if there's no history of recurrent contamination then you should probably still test the water once every year.

If you find that the bacterial contamination is recurrent and if you can't fix that by correcting a problem in or at the well itself (such as surface runoff leaking into the well) then you need to install a proper water disinfection system in your building to provider potable drinking water.

In comparison, periodic pouring of a bit of bleach down a well is arbitrary and gives absolutely no reliable assurance that the treatment is effective nor long lasting enough to provide safe drinking water.

If you want to assure that your well water is safe to drink I'd start by reading WATER WELL SAFETY & SANITATION, 6 STEPS-EPA