Well Drilling

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This is a very odd and rare situation.
 
Do you have water?
 
Ross, Mace, sounds like you need to come find water on my property:)
 
splitshot said:
Ross, Mace, sounds like you need to come find water on my property:)
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No freakin' way. If I recall correctly, you are near the entrance to the Charleough Gap trail entrance. I would have to look at maps and what not, but there is a very high probability that you have +4km of Oracle granite a few tens-100ft under your house.


I'm no hydrologist, but it is hard to find water in unfractured granite. You may be in a fault basin, but I would have to check some maps, that would increase your chances 100%, but depending on size of the basin you may not have much dependable water.

This is just the wild ass guess of a hard rock geologist, take it for what it is worth, I know nothing of the hydrology in that area.
 
No water.

No water yet. I bought 1340 feet of 1" pvc pipe yesterday. The ditch is dug, but is 98% rocks. So I've got to have topsoil hauled in to cushion the pvc from the rocks. It's gonna suck. For the moment, we are hooking up the pvc and just laying it in the ditch, will fill later. It doesn't get very cold here that often, if it does, I will have to leave water dripping.

We have to be moved out of our house next Wednesday. And I leave tomorrow for a duck hunt in Maine. Let's just say the wifey ain't real happy with me now.

Oh well, I have got my dad taking care of the pvc this week.

J.R.
 
Its probably too late but I use 200psi poly pipe when putting waterline in rocky areas. It will take a lot more abuse and can be bought in 100' to 500' rolls.
 
I have bought something to go under my pipe to cushion it. I bought concrete expansion joints. They are recycled rubber and are 4" wide and 1/2" thick.

I am going to lay the pipe on top of the rubber and duct tape/zip tie every five feet or so. Then when I dump top soil into ditch with the tractor, the pipe will not move off the rubber.

I think it's actually cheaper to buy this stuff than topsoil.

JR
 
GeoRoss said:
No freakin' way. If I recall correctly, you are near the entrance to the Charleough Gap trail entrance. I would have to look at maps and what not, but there is a very high probability that you have +4km of Oracle granite a few tens-100ft under your house.


I'm no hydrologist, but it is hard to find water in unfractured granite. You may be in a fault basin, but I would have to check some maps, that would increase your chances 100%, but depending on size of the basin you may not have much dependable water.

This is just the wild ass guess of a hard rock geologist, take it for what it is worth, I know nothing of the hydrology in that area.
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JR, don't mean to hijack here, but it's a good thread to get info on this.

As far as water in Oracle, from talking to various folks, (including neighbors and well drillers), seems it's a kinda hit and miss. Consensus is it lies in underground streams about 300' deep. Some wells have produced upward of 40gpm, with others around 3gpm.
Our community water is pumped 11 miles away because of this. Bad part of the story, (last I looked), is we pay the highest water rate in Az, and somewhere in the top 10 for the nation. So, there is a motivational factor to drill.
I'd like to hedge my bet, before I toss the dice on a $30k hole.
Any confidence on water witchers?
 
Here in the northeast most of the small community water systems have bedrock wells in fractured igneous and metamorphic rock (lots of granite around). 1,000 feet deep is pretty common. It's not uncomon to get yields in the 20-50 gpm range and sometimes more out of a 6" hole. The average residential well is around 350 feet with a yield of 4-6 gpm. there are all kinds of fancy ways to pick a well site. I use a pretty straight forward fracture trace method most times but sometimes follow up with geophysics (also keep a couple of bent welding rods in the truck just in case :cool:). I tell my clients that just randomly drilling holes is like playing slots at the casino. Doing a little homework brings the odds more in line with blackjack. In the end you gotta play if you want to win.
 
Paying someone to do a fracture trace analysis or surface geophysics for a domestic well is a bit on the expensive side.

If you can identify some large scale faults in your area you might have good luck with drilling into the associated fracturing. If there is not much by way of faulting/fracturing, solid granite sucks as an aquifer.

Water witchers are a waste.

From what your neighbors are saying it sounds like there are a couple of preferred paths in the rock that they are able to tap. It should not be hard to get copies of the local well logs to help identify possible production areas. That is free.

If you give us some more info about where you live we can probably give you a better idea of how bad off you are ;)
 
Ross knows the area, where would I locate the local well logs?

My neighbor down the street is a driller, he just punched a dry hole on his own property:eek:

On the other hand, two wells on either side of me, he found good water.
 
Azwater site is being a slow poke.

Thanks, I may owe you one, if it looks do-able:)
 
splitshot said:
Ross knows the area, where would I locate the local well logs?

My neighbor down the street is a driller, he just punched a dry hole on his own property:eek:

On the other hand, two wells on either side of me, he found good water.
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Follow Mace's advice. You'll have a much better luck following his advice than mine. The well log data will be much more informative.

Mace here is the challenge. He is near the backside of a metamorphic core complex. The footwall is all granite and gneiss. The back side has been excised by a number of high angle normal faults, some big and lots of small ones. The reason that it is so hit and miss there is that you never know if you are drilling on the footwall or the hangingwall of these fault blocks. The cover over the footwalls is pretty thin, 100ft or so.

There are so many small unmapped faults that it is a crapshoot, but if your neighbors have good wells, then the chances are better that you can hit that aquifer too.

I don't know a whole lot about real world hydrology and everything else I've learned from Mace. :grinpimp:
 
Hope I'm not intruding by adding my 2cents. From what I've seen a fault zone is necessary for adequate water for a residential setting. I've seen lots of wells that intercept joint sets within one rock unit that yield plenty of water for a house. Well logs are a great place to start but not always that helpful. Recently I saw the log of a rock well that yielded more than 100 gallons per minute and a similar log from a well less than 200 feet away that went much deeper and yielded less than 1 gallon per minute:confused:. Drillers don't always log the wells in a way that makes for good comparison but not everyone can or wants to pay for one of us high dollar geo guys to stand around and drink coffee. Again, the geology may be totally different in your area but in general terms looking for an area with some surface feature that appear linear can help with the odds (different vegetation types or a subtle topographic depression are sometimes good indicators). Drillers often just pick a spot where they can get in and out the fastest with the lowest chance to mess up their big dollar rig.
 
hydrogeo said:
Hope I'm not intruding by adding my 2cents. From what I've seen a fault zone is necessary for adequate water for a residential setting. I've seen lots of wells that intercept joint sets within one rock unit that yield plenty of water for a house. Well logs are a great place to start but not always that helpful. Recently I saw the log of a rock well that yielded more than 100 gallons per minute and a similar log from a well less than 200 feet away that went much deeper and yielded less than 1 gallon per minute:confused:. Drillers don't always log the wells in a way that makes for good comparison but not everyone can or wants to pay for one of us high dollar geo guys to stand around and drink coffee. Again, the geology may be totally different in your area but in general terms looking for an area with some surface feature that appear linear can help with the odds (different vegetation types or a subtle topographic depression are sometimes good indicators). Drillers often just pick a spot where they can get in and out the fastest with the lowest chance to mess up their big dollar rig.
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Kinda of a global statement but it really depends on the geologic setting that the well is in. Faults are typically not required for alluvial wells, however they can assist in increasing the production of a well if the alluvium is fine grained. In rock it really depends on the geology of the surrounding area. Fauts and fractures do typically increase the permeability of the host rock. Obviously if the rock is prone to weathering to clays (Tuffs, or units with high feldspar content for example) fractures/faults can easily become less permeable than the host rock. Even carbonates can have argilicious fracture fill. Not to mention on relative age of the fractures and the potential of them being healed or not.

The nice thing about well logs is that they are a great place to start. Typically they are not the greatest logs in the world. Hell, drillers fill them out, not geologists.. However, they still have depth to water (close proximity at least), general units drilled and, if the well was pumped, what it managed to produce... With a collection of them in your hand of the area of interest. You can get a reasonable idea of what to look for.

The idea of looking at vegetation patterns or surface expressions of fault structures is a good one. Just be aware that if the depth to water is significant, encountering the fault at depth will take a bit of research into the orientation of the structures. Commonly it is better to try to assiciate your well with the fractures associated with larger scale faults. Faults are both barriers and conduits to flow..

Splitshot, how far away are your neighbors wells? Is there significant relief between them? Depth to water approximations?
 
One is about 400 yards away, the other is approx 1200 yards. The dry (drillers) hole is about 2400.

Significant relief as in topography?

Depth to water runs 250' plus or minus.
 
yeah, topography..

linear bumps, hills anything like that?
 
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