I have a spring fed 1500 gallon plastic holding tank buried underground. I then draw the water into the house for usage…..and drinking.
Although it is great tasting and filtered I would like to add some bleach to the tank in order to kill any bacteria etc. that has accumulated during the summer.
Does anyone know how much bleach I should use?…..and how long I should wait after flushing the tank before drinking?
waiting on the revolution…………..
Replies
When it's a well, it's called "shocking" the well. If you google it, you'll come up with correct figures and methods.
If the tank were simply a storage tank, then the amount of bleach to pour in would be approximately equal to one of those little cups that comes with pepto-bismol... per 300 gallons.
So in your case, 5 of those little cupfuls.
That is to prepare the water for drinking. You would put in the bleach, and leave it for a day or two, then you could drink the water.
As for shocking, I would just dump a whole gallon in there and leave it for a day or so. Flush the tank. Allow to fill, flush again. And the day after the second flush, I'm guessing the water would be ok for drinking again.
I would be taking samples of the spring water and the tank water to a lab for some testing. Bleach may (or may not) take care of all the bad stuff that may be in the water and a lab may be able to tell you what to use and how much of it to use to treat it for drinking.
Even the most "pristine" mountain streams can have lots of bad stuff in them. Go ahead, ask me how I know that. - lol
Contact time for the household chlorine bleach is only 50 minutes. We have cabin we built for a customer years ago that required a holding tank. The HO hauls the water and pumps it into the holding tank. We only have the HO put 1/4 cup every time they add to the 500 gal tank. Works just fine. It does help that the tank is in a heated indoor environment. Colder environments will force the chlorine to take longer.
When we set up the system, we initially bought a chlorine drip feed system that put chlorine in as the water was used. We returned the system when we found out that there wasn't enough contact time for the bleach to really work.
We also use the bleach method for our water tanks when we go rafting or camping. It keeps everything clean.
My tank has a fairly large constant overflow....comes in one side out the other.....the spring is never (so far) dry.........but I wonder about bacteria etc..........since I'm sure at least some of it will flow out the overflow.....would you think a gallon placed in the pre-tank crock and allowed to flow into the large tank would be about right?I plan on turning on all house spigots and just let them run until the smell is gone.....
waiting on the revolution..............
I got our information the system we set up from a water/wastewater engineer. Pay for some time and find out for sure.
By the way bleach will only take care of bacteria. But the arsenic, nitrates, etc. will still be there. The nitrates are from septic.
I just had the same problem last week. Look for a post named "rotten eggs in my well" In the general discussions forum. There is a link in the first couple posts to an article that tells you exactly how and how much.
To shock chlorinate a water supply, a typical recommendation is to raise the concentration of chlorine in the water to 100 parts per million. For 1500 gallons of water, using household bleach (which is usually about 5% chlorine) 3 gallons of bleach would do it.
Here's a recommendation from Vermont for an overflowing spring: "For an overflowing spring, use fast-dissolving 65 percent calcium hypochlorite pellets (3 ounces for every 100 gallons of water or about 2 feet in depth). Pellets are available at pool supply or hardware stores. Caution: The pellets should contain ONLY calcium hypochlorite—NOT algicides, chlorine stabilizers/conditioners, acids or other disinfectants. (These may be acceptable to use in swimming pools, but are not safe for drinking water.)"
As has already been suggested, you ought to have the water tested. It may be fine.
thanks everybody...........
waiting on the revolution..............