Water well subsiding and questions about pumps and slotted screen

[JacksonK]

Hi Guys

Small crisis at the family beach house. The water well is starting to subside and will eventually collapse into the borehole.

This is a typical Nica water well, which was hand dug~ 5 diameter and 14 feet deep. The side wall completion appears to be concrete, but I'm not sure. The well completion at the surface was just a simple brick enclosure around the diameter to keep out debris. The base of the wall is starting to slough, and the well will collapse. It was only built about 5 year ago. The pool water or rain water discharge may be facilitating the borehole collapse, but I'm not sure as I only can see pictures of the surface completing subsiding. FYI- we have never even used the water from this well, as Las Penitas has municipal water; however, I would like the option to obtain water from the well. Water from the well would only be used for non-potable uses.

Above is the background story, and now for my questions:

What types of electrical pumps are typically available in Nica?

Can these pumps small enough to be placed pipe (i.e grundfos pump/keck pump?).

I was thinking about brining down a peristaltic pump (i.e a surface mounted pump with a poly tube going down the pipe casing).

Can you buy slotted screen in Nica?

Slot size I'm not sure as to what I need as I don't know the grain-size of native materials. However, we may just make our own, so is 4-6 inch diameter sch 40 PVC available?

My plan was to backfill the 5 foot diameter well with 4 feet of gravel to create a void space for water collection. A slotted screen would be placed into the gravel connected to casing with a 3-4 foot riser coming out of the surface. After the gravel, the 5-diameter hole would be backfilled with soil (and the demo'd well blocks).


PS... it's the family beach house when it works, but seems to be mine when it needs repairsLOL!

[kwah2249]

Not sure on item prices and availability. If you have that much diameter in the well it might be easier to get concrete well liners and lower them in (might need to pump dry), then back fill with gravel around them since it's only 14' deep. If you reduce down to a 6" pipe it won't hold much volume and you will have a hard time drawing a steady flow of water. The screens will most likely get clogged up, especially if you top fill with soil. If something goes wrong after the 6" pipe is installed and backfilled it will be very difficult to repair.

Will cost more to do the concrete liners but you already have the cost of the original well. The concrete rings will keep the well useable and it should balance out in equity value. Just my 2 cents, sounds like everyone is dumping the project on you so do what works best for ya.

[Just Plain John Wayne]

Think I would go with the rings as well....

[billbudsocket]

Why not just have a posero clean out the hole and line the well with brick? That seems to be the most common practice to build a well in Nicaragua that will last.

[kwah2249]

Bricks would probably be a good fix also. But if you do the rings correctly you can add more on later. Just gotta pump it dry, dig out from the bottom, and slide'em down (safer also since you dont have the collapse risk).

[JacksonK]

Good ideas.... from what I'm reading is that a sustainable and Nica solution is needed.
I'll have to get ahold my contractor to see what he can actually build, as I am not in Nica.

[KeyWestPirate]

Good ideas.... from what I'm reading is that a sustainable and Nica solution is needed.
I'll have to get ahold my contractor to see what he can actually build, as I am not in Nica.

What size are the concrete well liners (rings)??

Sounds like a good solution. Quality of bricking varies a lot, concrete would be a sure bet.
What's approximate cost? Brick is cheap, but for a well, I don't think you are looking at first cost.