Suggestions - borehole in sandstone?

[Nomad]

I’m looking at ideas as we have a fresh water well in the garden (Portugal) and the water level is near critical.

We also have a small stream a few yards away. The stream is dry for most of the year but takes surface water runoff from winter rains to the local river.

It would be ideal if I can use the runoff water to fill the well.

Thoughts are :
How to drill through sandstone from the stream to the well (and install plastic dainpipe liner).

Alternatively, dig a “sump” in the stream and fit a 240v submersible pump.
Not ideal as it will need and electric supply + running costs)

Suggestions welcome, I guess the main question is “can I drill a 15ft long, horizontal hole through sandstone? How?"

Random web photo (not the actual place) to give an idea.

 

[rtcosic]

Self powered pump from the stream?

 

[Kram]

Sandstone will be easily eroded so any hole might want some kind of resistant liner.


If the well is supposed to be of drinking water quality, you may want some filtration on the incoming feed from the stream.


A 5 meter hole is going to need a few extensions, but sandstone is usually easy to drill.

 

[Nomad]

Agree a liner will be needed to avoid future problems - standard drainpipe or similar (exact size & pipe isn't critical)

Filtration is already sorted

Background about the layout :
The well in question is for irrigation only, we have a 2nd independent well to supply the house.
The wells are a few yards apart and not connected,
Experience says water from the irrigation well will filter through the sandstone to fill the other well. Water from that well goes though several filtration stages before it gets to the house.

 

[Pigeon_Droppings2]

On the discovery channel there's a show called homestead rescue...might be worth a watch. A lot of episodes have ideas for creating water sources using what's available to hand.

Based on the above shows that I watched they often use a perforated steel tube to form a sump...back filled with stone...then pumped from inside the tube. Is solar an option for the pumping maybe?

 

[Erie Fred]

Your wanting to take surface water, and put it onto the aquifer ?

 

[Nomad]

Photo showing inside the well and the sandstone “bedrock” material.


We have historical photos from late 1970s showing water level much higher, up where the recent photographer was standing!

 

[6ply]

Your wanting to take surface water, and put it onto the aquifer ?

That's what I thought. Seems to bypass the usual route for percolation and natural filtration?

 

[Seadog]

Using it as a cistern.

 

[Agroshield]

Can you not divert/pipe the stream from a point higher than the top of the well?

What volume is currently available in the well (from current water level to the top)? Piping the stream into the well, that is the maximum volume of water you will gain.

What volume do you withdraw from the well in a given time period? So how long will the top up last?

What is the flow rate of the stream? How long will it take to top up the well?

Once the well is full, how do you switch off the flow from the stream? Or what are the consequences of the well overflowing?

You might need some kind of 'first flush' diverter (as in rainwater harvesting systems) to stop all the dross from the first flow of the season (i.e. when the stream first starts flowing) going into the well

 

[addjunkie]

20k drills you a proper bore hole

 

[Pigeon_Droppings2]

Will pumping water into an existing well work? Won't the water simply be absorbed by the surrounding water table.

I thought you were pumping the stream into additional storage tanks.

 

[gaz1]

as ive looked into it as i need a reference to get under the floor to insert a new water mains

first off understand direction and this gives you an idea of that

if you want a basic drill then you can use another type

there is another way

 

[colnerov]

ISTR, you need a licence to interfere with a water course in the UK, big fines. Or are you elsewhere? Is it the same, if you are.

https://www.gov.uk/guidance/owning-a-watercourse

 

[gaz1]

sandstone will fail with water and a constant drilling also used with the egyptians who also used sand to drill through with a copper bit end

so is it possible with the tools nowadays yes just need to get the drill speed lower

i was looking at 5kg drill or a heavy duty impact drill also cheap from tool station

youtube has changed again and is now showing restricted searches so i will have to go find the downloaded video that ive already saved

 

[Robotstar5]

On the discovery channel there's a show called homestead rescue...might be worth a watch. A lot of episodes have ideas for creating water sources using what's available to hand.

Based on the above shows that I watched they often use a perforated steel tube to form a sump...back filled with stone...then pumped from inside the tube. Is solar an option for the pumping maybe?

Good old Marty Raney

 

[reb78]

Will pumping water into an existing well work? Won't the water simply be absorbed by the surrounding water table.

I thought you were pumping the stream into additional storage tanks.

Exactly what I was just thinking. I'd imagine the well depth is the same as the surrounding water table - the well is just where you access that reservoir.

 

[Nomad]

Thanks everyone, replies ...

The water table in the region is low due to years of drought. This is rural land with nearest neighbours half a mile away, no residential or commercial areas to contaminate the runoff water, adding to the aquifier isn't ideal but shouldn't affect anyone or anything as there's nothing nearby.
Adding the this well seems to be a way to hold the runoff water and let it filter through the bedrock to the house well (where it's badly needed)
It should also raise the water table near the wells rather than disappearing as runoff to the rivers.

Not able to tap into the runoff upstream (stream has a gradient but very little, tapping from a point above the well would need to be several hundred yards away).

There's no risk of the well overfilling, the stream is a couple of meters below ground level compared to the well. Stream has flowing water for maybe a couple of months every winter.
Also I'd guess it would take a few winters of steady heavy rains to fill the well (and filter to the house well) if I can tap the stream using a drainpipe or similar bore.

Volumes, capacities, flow rates, usage - all good points but for the last couple of years we have been cutting usage to essentials only, adding *anything* to the levels in the wells should move us away from critical levels.

Estimates.
The well in question is 8m diameter, it now has about 1m of water in it (50k liters), to get back to 70s levels will raise another 4m (5m total = 250k liters)
Filling this well will filter through bedrock to the "house" well (similar dimensions ie capacity to hold another 200k of runoff water).

"Rainy season" lasts for maybe 3 months with some steady rain that could be captured using a standard drainpipe or similar.
"Flash floods" overwhelm main storm sewers so no system I can DIY will be able to capture that volume at that rate.
Diverting the whole stream into the well would be overkill and would also send a lot of garbage in with the water. Not an option.

"First flush" makes sense, I can see a sump that needs to be cleared at the start of every rainy season.

We already have a 100m borehole drilled decades ago but never connected. It would need 100m of piping + electrics running, also a high volume / high pressure pump designed to fit down a narrow pipe. All expensive if tapping the stream is a zero-running cost option needing no expensive pumps.

Location: this is rural Europe, new boreholes or wells need permission (recent legislation due to drought..),
I don't think the pipe I'm considering needs any permits but I'll check once I know if it's practical.

 

[drjim]

Can you not stick an mope pipe in the stream further up, maybe with a small dam to guarantee head of water and just let it run into the well/sump? Easier than drilling holes through sandstone/

 

[julianthegypsy]

Thanks everyone, replies ...

The water table in the region is low due to years of drought. This is rural land with nearest neighbours half a mile away, no residential or commercial areas to contaminate the runoff water, adding to the aquifier isn't ideal but shouldn't affect anyone or anything as there's nothing nearby.
Adding the this well seems to be a way to hold the runoff water and let it filter through the bedrock to the house well (where it's badly needed)
It should also raise the water table near the wells rather than disappearing as runoff to the rivers.

Not able to tap into the runoff upstream (stream has a gradient but very little, tapping from a point above the well would need to be several hundred yards away).

There's no risk of the well overfilling, the stream is a couple of meters below ground level compared to the well. Stream has flowing water for maybe a couple of months every winter.
Also I'd guess it would take a few winters of steady heavy rains to fill the well (and filter to the house well) if I can tap the stream using a drainpipe or similar bore.

Volumes, capacities, flow rates, usage - all good points but for the last couple of years we have been cutting usage to essentials only, adding *anything* to the levels in the wells should move us away from critical levels.

Estimates.
The well in question is 8m diameter, it now has about 1m of water in it (50k liters), to get back to 70s levels will raise another 4m (5m total = 250k liters)
Filling this well will filter through bedrock to the "house" well (similar dimensions ie capacity to hold another 200k of runoff water).

"Rainy season" lasts for maybe 3 months with some steady rain that could be captured using a standard drainpipe or similar.
"Flash floods" overwhelm main storm sewers so no system I can DIY will be able to capture that volume at that rate.
Diverting the whole stream into the well would be overkill and would also send a lot of garbage in with the water. Not an option.

"First flush" makes sense, I can see a sump that needs to be cleared at the start of every rainy season.

We already have a 100m borehole drilled decades ago but never connected. It would need 100m of piping + electrics running, also a high volume / high pressure pump designed to fit down a narrow pipe. All expensive if tapping the stream is a zero-running cost option needing no expensive pumps.

Location: this is rural Europe, new boreholes or wells need permission (recent legislation due to drought..),
I don't think the pipe I'm considering needs any permits but I'll check once I know if it's practical.

If you already have a borehole, why don't you stick a windmill on top of it? It's one area where wind power really excels. You might be able to find an old one off an abandoned farm or a cheap second hand one.