Well filtration - thoughts and recommendations?

[sebvad]

Hi folks - we've been on a well for over 40 years, problem free. A month ago, our water suddenly (as in overnight) had a great deal of sedimentation in it - far more than our single 20um sediment string filter could address. Not sure what changed. Well is 360 feet deep with the pump at 260 feet and the water level a good 100 ft above that - so there's plenty of water in the well, and it's a lined well. Since the sedimentation problem showed up 3 weeks ago, i've gone to a 1 micron string filter, but the issue persists, although it has improved.

Water is a pH of 6.8 with 5 grains of hardness, TDS of 73, iron is barely registering on the colometric chart (a little bit there, but nothing of concern). I've flushed the pressure tank multiple times, and have run approximately 18,000 gallons worth of water through the hose to attempt to flush the well a few times.

We've just had the local water / appliance store out, and they went into full blown sales mode - recommending a water neutralizaiton system, a water softening system, a water re-mineralization system for drinking, etc etc - a good $7k in systems. The main issue i want to resolve is the sedimentation - there's too much dirt/silt getting through. While i have little doubt all the systems they're recommending will improve my sedimentation issue, it feels to me to be the path of most resistance, and am hoping that some of you who have travelled this path already could contribute what you did and how effective it was to give me alternate perspective to consider.

Thanks in advance for any insight/suggestions y'all might be able to offer!

 

[Reach4]

I am not a pro. I am not speaking from experience.

How far down does the casing go?

Suppose the casing has been getting mudded up with sediment at the rate of 2.5 ft per year? In that case, a well cleaning could be good. Try searching for well cleaning air on Youtube. Or just have them lift the pump 50 ft higher maybe.

If you put some of that sediment into a glass and stir it up? How long does it take to settle out sediment? If fairly fast, a TwistIIclean filter might be good as a pre-filter for the bigger stuff. That would be cheap enough.

A backwashing filter with sand or some other media might be good.

 

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[sebvad]

Thanks Reach - good question, i'll need to find out on casing depth. This well's only 3 years old, and the pump sit pretty high up off the bottom, so i'd be surprised if that was it, but certainly something worth finding out! Most of the sediment we have getting through is pretty small at this stage - taking hours for it to fully settle out.

 

[Reach4]

Most of the sediment we have getting through is pretty small at this stage - taking hours for it to fully settle out.

I was thinking of the sediment that the string filter took out. I expect that is the sediment that you are talking about, since visible sediment is not going to make it through your 1 micron filter.

 

[sebvad]

I'll rinse a filter cartridge and see how long it takes to settle. I've got a micrometer, and have had readings as small at 2 um and as large as a few hundred (as you likely known, a micrometer will simply read the largest particle it 'sees'). We are still seeing sediment after the 1um string filter - colloidal clay perhaps? dunno - my micrometer won't go submicron in it's readings i'm afraid.

 

[Reach4]

Oooh... hope it is not colloidal clay. That would be something that you would want your well people to try to fix.

How big is your casing diameter?

 

[sebvad]

assuming the pipe stand above the well is approximately the same diameter as the casing - it's about 6"