Pressure washing a shallow well casing

[K H]

Ok guys, I've got a pretty normal problem, a slightly odd well, and a slightly odd idea I would like some feedback on. Plus a request for other ideas.

My well: I have a 2' metal cased well 22' deep. So it's not a gallery well and it's not really a typical drilled well (at least for my area). It stores a few hundred gallons of water, delivers at 12 gpm, but it doesn't recharge nearly that fast. I'm not sure how to safely test the recharge but if I keep long-term use to 2.5 gpm I don't run dry. That's hard when using it for my permitted use of domestic irrigation.

My problem: The well now likes to run dry during heavy usage but I'm 99% certain the water table isn't dry, just my hole in the ground. The neighbors use more landscaping water and don't run their shallower gallery wells dry.

My theory: I think my perforated casing has scaled, ironed, and silted up.

Preferred pro solution is an acid wash and brushing but because of my metal casing and medium storage volume the acid is very expensive and brushing is not too likely to be effective.

Other professional olutions:
New well: $$$$$
Cistern: $$$$

So I'm looking for cheap solutions. Any ideas?

The one idea I have is to get a 20' telescoping pressure washing wand and use my pressure washer to try to knock sediment, silt, iron, or calcium off the perforated casing. That wouldn't work with a narrow casing but I have this weird 2' casing.

Here's a slightly stupider idea: buy a large RO generator for the house (we have a kitchen sink sized RO system right now). Make RO water into storage (not sure what that storage is) while running the well low. Put RO water in the well. Go on vacation for a week. I have no idea if RO is actually grabby enough to accomplish anything sitting in the well for a week. If I own the RO generator, I could repeat this task. I don't know how I would store 250-300g of RO water.

So questions:
- has anyone ever used a pressure washer to try to refurbish/maintain slotted or perforated metal casing?
- is there a better approach I'm not thinking of?

Sorry if this is an odd request but I'm hoping for some experiences, advice, or ideas beyond 'drill a new well'

 

[LLigetfa]

It would be hard to control the end of the long wand as the force of the water coming out at an angle will push the wand away from the surface you want to clean. I got an 18 foot wand to wash my house siding and I have gravity working for me to counter the force of the water.

You would need to make some long outrigger wheels that ride the opposite side.

 

[Sponsor]

 

[Valveman]

They make devices to "jet" a well that work like a pressure washer. So yes sometimes that can help. With 2" casing I would just drop in some Nuwell tabs, chase it with 10 gallons of water, and let it set overnight. The jetting won't get to the outside of the casing like it should and the tabs will probably work better.

 

[Reach4]

I have a 2' metal cased well

So to be clear, that is 24 inch or so diameter.

 

[Valveman]

So to be clear, that is 24 inch or so diameter.

Good catch. I was seeing that as 2" with my old eyes. Lol!

 

[K H]

Yeah, it's a 24" perforated metal casing. Sorry, I should have stated it that way. The information I currently have from the one local well company willing to talk to me is that there isn't a good brushing solution. I discussed an acid and brush treatment with them but between the challenge of brushing a 24" casing and the extremely high cost of acid, both because it has to be dry acid for the metal and because of the high volume of the well, the company and I felt it was not cost effective. We'll probably consult at some point about a new well but honestly, I hope that if I can figure out how to descale the perforations a little, I'll be ok for a long while.

 

[Valveman]

You could still make an air jet system than would vacuum stuff off the bottom. But it is hard to brush or air lift a 24" casing.

 

[LLigetfa]

If you look at how a rotary surface cleaner works, you might be able to use that principle to pressure wash the screen.

 

[LLigetfa]

Take a look at Mosmatic for ideas and the parts to build your own.
https://www.mosmatic.com/us/products/high-pressure/

 

[ZorLence]

Thanks for the answers in the thread. I am also looking forward to cleaning my well, and I didn’t know that one can use pressure cleaning.
I know that guys from https://sparklewash.com/nashville/ do that in our city, and I will just call them and ask whether they do well cleaning. Is there something I should know beforehand? Is it safe for the water that is down there? It is safe to use any chemicals, or should the cleaning be done with water only. I am not a professional and just want to ensure that I have clean water in my house. Pressure cleaning is one of the safest ways to clean something because you can use water pressure without any detergents.