Question- water well after flooding

[David Wayne]

I am wondering what you folks do for your water wells after a big flood like in the Carolina's now? The news is saying the flood waters are toxic from everything from paint, chemicals, waste, both human & animal. Well casings are not sealed, so all this is flowing right down through the top into your ground water. How do you make it safe again?

 

[raptorterry]

Great question.
Subscribed

 

[RedNeckRacin]

There isn't anything you can do for chemical contamination other than keep testing the water. As for the E Coli from the waste, you can "shock" the well with some chlorine.

 

[Ken]

I am wondering what you folks do for your water wells after a big flood like in the Carolina's now? The news is saying the flood waters are toxic from everything from paint, chemicals, waste, both human & animal. Well casings are not sealed, so all this is flowing right down through the top into your ground water. How do you make it safe again?

There should be a pipe seal at top of well maybe not liquid tight but sure would slow the amount of fluid entering. then a gallon of diluted Clorox to sanitize with a long period of pumping to remove any standing water above normal height of fluid in well.
ken

 

[oosik]

When I was in Anchorage - we would occasionally have a flooded well. The official procedure was exactly as RedNeckRacin spells out in post #3. In all my years as Director of Environmental Health there in Anchorage - only saw one flooded well when the casing terminated above ground - all the remaining flooded wells were in pits. Well in a pit = a catastrophe waiting to happen.

 

[Katahdin]

One gallon of household bleach will disinfect 200 gallons of water. Calculate how much water is in your well add as much bleach as necessary. For best results, mix the bleach with several gallons of water before adding it to the well.

After the bleach is in the well, run the tap furthest away until you smell the chlorine. Then do the same for the rest of your taps in your home. It will take a week or two to get rid of the chlorine taste and smell. A Brita water filter helps get the chlorine taste out, or drink clean water from another source.

I recently went through this exercise, my well cap was in a pit five feet below grade. The well became contaminated after heavy rains. I paid $1500 to have a pipe extension welded on and raised above grade. The price included removing and reinstalling the well pump, which was 175 feet deep.

 

[turnkey4099]

When I was in Anchorage - we would occasionally have a flooded well. The official procedure was exactly as RedNeckRacin spells out in post #3. In all my years as Director of Environmental Health there in Anchorage - only saw one flooded well when the casing terminated above ground - all the remaining flooded wells were in pits. Well in a pit = a catastrophe waiting to happen.

Another reason for not having a pit! I can't believe people still putting water works in a deep hole in the ground.

 

[Ritothebull]

Many folks in my area had iron bacteria in their wells and tried different methods to get rid of it, every well guy had a different idea of how to do it but none of them worked and some ended up installing expensive chlornation systems. I did mine about 6 months ago with good results using this procedure, the recirculation of the chlorinated water back into the well is the important part, they were just pouring chlorine into their wells and flushing the lines, the bacteria usually returned in a week or so.

Well Disinfection - EH: Minnesota Department of Health

 

[David Wayne]

Thanks for the answers.

 

[ning]

I shock my well every few years for good measure (we get iron bacteria, which is icky and a nuisance but not a health hazard). I find that "run it till you can't smell it" doesn't work well because all I can smell after a bit is chlorine, so I get some chlorine tester from a pool supply - put a drop in some water and see if you get yellow. At first, one drop in running water over the ground stains so dark it's almost like you dripped blood (high chlorine concentration), but eventually after pumping out you get to where you can't really see any yellow even in a glass held up to the sky. That's when I stop.
Don't water plants with that water until you don't detect the chlorine either.

 

[Alien]

We had a problem recently and normally have very high quality water. 15 ppm TDS. However it suddenly developed a smell so we had it tested and it had high levels of ecoli for an unknown reason. Our bore is completely sealed so something entered the aquifer somehow. We ran the water for several hours until it seemed clean and now we have fitted (in conjunction with the normal filters) a UV treatment system. . We have a pressure switch that operates the UV as soon as a tap is turned on.
It seems to work well but we haven't had the water tested again yet.
In the future we will be completely refurbishing the bore and pump system. It just needs some money first.....

 

[David Wayne]

I would guess multiple wells could be in the same aquifer, so multiple potential sources of contamination.
Thats basically why I ask the original question. In my mind I see a large lake so to speak under ground, that gets flood water-chemicals... You cant pump it all out, so I guess just treat what you can and let time dilute the rest to safe levels.
I do feel bad for those who have to deal with this.

 

[oosik]

Many times when there is a large storm and many private wells are flooded - the aquifer could be permanently contaminated. The contaminating agent(s) could continue to enter the groundwater for tens of years following the storm. Recognize - contaminants entering the ground water thru flooded wells is a very rapid situation - - contaminants entering the ground water thru saturated soils can go on for decades.

 

[DrRod]

If you pour a gallon of bleach down your well, can it hurt your well pump? I mean, bleach is caustic stuff and if it splashes all over your electric pump can it eat through wires, insulation, motor components, etc.?

 

[aczlan]

If you pour a gallon of bleach down your well, can it hurt your well pump? I mean, bleach is caustic stuff and if it splashes all over your electric pump can it eat through wires, insulation, motor components, etc.?

That is why you would pour the bleach down the well and then recirculate water back into the well for a while. That way it washes everything down and the bleach that may have gotten on to the wires should be diluted. The pump should not be an issue as your pump should be underwater if it is in the well.

Aaron Z

 

[oosik]

With a submersible pump - you will not hurt the pump, piping or wiring by dumping bleach directly down the well. However, what will happen is the bleach will react with the steel well casing and loose a lot of its power to disinfect. We always recommended - five gallon bucket - one gallon of bleach - fill the bucket up with clean water. Dump this down the well. Turn on all your faucets until you can smell bleach. Use no water for the next 24 hours. After 24 hours use water as normal - it will be several day before the chlorine has dissipated to the point where you can drink the water. Use alternate supply for drinking.


The thing about a submersible pump - it is at least ten feet below the water surface in the casing and it can be as much as 100 feet below the water surface. Raw bleach dumped down the casing will not land on the pump and will not damage the wiring or piping.

Bleach should be mixed with water, before use, for the reason given above.