Question- water well after flooding

[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.