Well water suddenlly dirty!

[Mets5rocks]

Hey there all,

I have a roughly 4 year old, 90ft deep (with a 50ft long, 6 inch casing) water well that I've never had a drop of trouble with (other than hard water) until this week. Pressure is fine best I can tell, but all the sudden I'm getting a lot of sediment that ranges from a fine grey clay like silt to courser brownish sandy stuff. It had rained considerably here for about a week, probably a week and a half ago, so at first I thought the well was just a little stirred up from all the increased rain runoff which happens on occasion, but nothing like this!

So thus far here's what I've done:

I changed the whole house sediment filter that's a 30 micron filter ahead of the water softener. When that didn't work I added two more stages of sediment filtration at 20 micron and 5 micron filters in succession. I got the water to run fairly clear with the filters but was having trouble bleeding the air out of the lines in the house.

So I hooked a hose to the spigot on my pressure tank and noticed it would run like **** for maybe 20 seconds then the pressure would fall off quickly. So basically when I emptied the pressure in the tank the pump wasn't keeping up fast enough. So I went back to where I'd set up my filter system and hooked the hose up to the test spigot I'd plumbed in right after the filters and got the same thing. I figured one of the filters were plugged, so working my way backwards I started pulling a filter, then checking. When I got to the 20 micron filter (pleated style) it was just loaded with that fine grey clay like silt! So I pulled that filter and bam, sustained pressure is back! But now I again have the sediment issues! Anybody have any thoughts?

 

[gwdixon]

Sounds like you had a cave in down the well. We periodically have the same thing here...especially after the pump was replaced with a newer and stronger one.

There are sand / silt filters that can be attached near the well's water tank that work quite nicely. It has to be emptied of the debris on a regular basis (there are timed controllers available).

This is what I put on the feed line between the pump and the holding tank:

SandMaster Home Sand Removal Separators

You may have to have the pump lifted a bit to get it clear of the cave in. A pump / well repair person could give some advice.

 

[Mets5rocks]

Thank for the input! Where do you get them if I decide to do something like that ?

 

[gwdixon]

Thank for the input! Where do you get them if I decide to do something like that ?

Hmmm...I don't recall where it was purchased. A Google search was used and then the price + shipping was evaluated. I'm a cheap SOB in that way.

I got the SMP-10.

If this Google link works it will get you started:

https://www.google.com/search?q=SMP+10+sandmaster&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-USfficial&client=firefox-a&channel=sb

 

[Mets5rocks]

Thank you sir, I'll check it out! How often do you have to empty yours?

 

[Dave M7040]

What can happen to cause your sudden change in well conditions is the drilling of another well on a property in the neighborhood.
The drillers use compressed air to blow the spoils from the drill to the surface. The effect of this air pressure can travel along water pathways underground and move sediment away from the well they are drilling and possibly towards yours. Sometimes a process called hydro fracking is used to increase the yield of a well. The well is sealed and very high pressure water is injected into the well with the hope that water passages will be opened up increasing yield. This process can cause problems in neighboring wells. I have seem cases where a well driller just went back and forth between properties blowing the sediment from one person to another and then go to that person and do the same process which move the problem back to the first person.
Well drillers can "clean" a well using a large air compressor like a jack hammer would use. They put a length of steel pipe on the end of the air hose and lower it to the bottom of the well. At that point they turn on the air and a large slug of water and mud will shoot out of the well. They do this a number of times over a couple of hours and most of the existing sediment is removed.
There is likely someone within your state government who is both responsible for and knowledgeable about wells in your area. This could confirm or disprove the possibility of a collapse within your well based on local geology.
Dave M7040

 

[troutsqueezer]

My well is 30 years old, 175' deep. I would get sediment after heavy rains for the first 15 of those years.

 

[gwdixon]

Thank you sir, I'll check it out! How often do you have to empty yours?

Every couple of days to a week between flushing. It depends on how much water is being used. Summertime requires more flushes while winter requires fewer.

 

[Dr_Zinj]

Ithaca NY sits in the bottom of a partially filled in glacial valley at the southern end of the Finger Lake, Cayuga Lake. You said your well goes down 90 feet; so I'm assuming that's through glacial till or lake deposits, and the bottom is probably just above bedrock. I don't know precisely where your well is, so why it's plugging and what's plugging it could depend on whether your on till, or lake deposits.

I suspect lake deposits since it should like fine silt/clay is getting into your system. Sounds like a collapse or subsidence in the underground aquifer might be the cause. And that happens because you probably have several hundred to several thousand people all pumping out of the ground and either depleting the ground water enough to cause shrinkage of the soils, or everyone is pumping out a little bit of silt (not enough to notice on a day to day basis) leaving a void underground that eventually collapses, and silts up your water again.

I remember a field case study our advanced geology class went on down on one of the branches of the Schoharie Valley. A couple of acres of a dairy farmer's field had subsided 10 to 15 feet for no apparent reason. The stream in the valley was a hundred feet or so below the level of the field and at least a half mile away. No visible sign of erosion. No sign of slippage like that landslide in Washington State earlier this year. Just a straight drop. We suspect that the silt and sand underlying the field was being slowly transported underground to the stream and being washed out slowly enough to not be measurably noticeable in the water or the steam bed.

 

[SPIKER]

Have you watched & listened to the pump? Is is cycling on and off a LOT more than normal? Some times a crack/leak in the line will let water spray back into the well. This stirs up the well water and will not let it settle. Shut off all the water and check the well pressure to see if it starts to slowly drop over time.

Other cases is underground earth quakes even little ones can stir em up too. Usually only a day or two.

After rains you SHOULD NOT see any cloudiness that is signs of surface water contamination... No surface water should get into the well, check for signs of depression on/around the well head. Use some Benoite clay and soil mix around it to seal it up. The fine silty stuff may be Benoite getting washed off the well sides tho if the line is leaking.

Other suggestions about nearby drilling activity can also cause it.

Mark