Where should we locate the well?

stumpfield · Mar 10, 2006

After reading the posts. JimBrown's right: I think I'm taking the wrong approach. Actually, the highest spot where we want to place the water tank is the easiest location to get to. It's almost perfectly flat. It's on a ridge. Not the highest part of the ridge but it's the highest location on our property. We don't have any concern about the initial cost. We want the most reliable water system. As close to city water convenient as possible except for the fact that I'm the city /forums/images/graemlins/grin.gif. Anyway, I always thought it's not a good idea to drill on ridge /forums/images/graemlins/confused.gif

techman · Mar 10, 2006

A single water line to flow bidirectionally is standard practice in nearly all water systems. You run the line from the tank to the house and "T" in the pump connection anywhere. The pump will have a check valve so that water can only go from the pump out.

Be aware that with a tank like that, there will be a vent to atmosphere, so that the air can make up water height differences. Problem is that this allows "things" to grow in the water. Bacteria, algea, etc. It will be likely that you will need to treat the water with chlorine.

One other consideration is to locate the storage tank near the home, perhaps underground. The house can be fed with a readily available pump that will provide the desired water pressure. The pumps operate only when there is a water demand. They are available in 120 VAC as well as 12/24 VDC. (Think RV water system). You might need two pumps (parallel with check valves) so that one can operate when AC is on and the other off of battery/solar when no AC is present. The cost of the pumps is way cheaper that the cost of the piping/trenching for the gravity feed. In an emergency, a hand pump could be used as well.

Just a thought. It keeps the system close to home (literally).

Paul

Egon · Mar 10, 2006

Try and find out what the geology of your area is like. Also check and see if there is recorded information on surrounding wells.

Egon /forums/images/graemlins/grin.gif

3RRL · Mar 10, 2006

Spiker,
You're right about finding the "spot" but this part is not, according to my hard rock well driller. ( if it IS solid granet then you will not get much water below it unless it has fractures for the water to penetrate it. not to mention getting the drill through it)

He told me that is the best place for hard rock wells. You just need to locate a fissure in it. Their drills are like a hammer drill with carbide knpbs on them. The cay cut through granite like you can't believe. If you're lucky enough to hit quartzite (sp) that an even better sign. He said the canyons and ravines that carry water are the worst to drill because the rock in those places have been squeezed together so tight that there are very few fissures in those locations. Going up on a ridge is a much better alternative. Funny, I thought the same about drilling in the ravine until he explained it to me.

Here's a picture of when he started to hit the quartzite rock.

3RRL · Mar 10, 2006

techman has some good advice on the water tank. For that reason, we are drawing right from the well via a pump. The large tank is primarily there to satisfy the fire dept code in our area (min 4000 gals for them). We will have a valve located on the tank that can feed the house, but it has to be located above the 4000 gal mark. (according to code)

If you're off grid, your solar system will run the whole house and such via an inverter, and the 120v pump without the need for 12/24v pump, I think.

stumpfield · Mar 10, 2006

The geology in the entire sierra foothill is as described by 3RRL. We are on the side of a gaint granite mountain. Underground water flows from the high elevation sierra nevada east to west. Everything ends up at the san joaquin valley which has a water table and plenty of water. Wells down there are in 1000's gal/min. Drilling any where in between will have to intercept fractures in the rock to get water. I searched the net but found nothing about finding favorable locations to drill in the sierra foothill. I did find a research paper on finding water in pennsylvania bedrock. The geological condition sounds very similar. I can't remember the link and not able to find it anymore. I did save a hardcopy. (don't know how to post a picture here...)

It said something like this:

-------------
Because most groundwater in Pennsylvania's bedrock flows through fractures and openings between rock layers, locating a well in an area with a high density of fractures may result in a higher yield, if the well is to be drilled into a bedrock aquifer. The more factures that a well intersects, the better the chance of encountering an adequate supply of water.
Determining the rock unit and the fracture density require that the person selecting the welll site have some geological knowledge. A simple way in for anyone to increase the likelihood of a good yield is to locate a well in a valley. Other things being equal, wells drilled in a valleys yield more water than those drilled on hillsides or hilltops.

The valley exist because the rocks are more easily eroded there, indicating that is a zone of weakness. The source of that weakness may be a concentration of fractures......
The rocks beneath a valley are more likely to be highly fracture than rocks beneath hillsides and hiltops.....

EddieWalker · Mar 10, 2006

( He said the canyons and ravines that carry water are the worst to drill because the rock in those places have been squeezed together so tight that there are very few fissures in those locations. )

OK, call me slow, but this just doesn't make sense to me. Ravines and canyons are caused by erosion, not movement of the plats. What would cause them to be sqeezed together?

I'm of the opinion that those locations are where the magority of the underground water suplly comes from. Rain doesn't come down heavy enough saturate the land down hundreds of feet. It just travel down there along a path of some kind. I always though this happened in the mountains from the crackes in the rock, and the the vast majoritiy of it came from lakes and rivers.

Could it also just be a story that well drillers tell to avoid having to deal with the absolute most dificult location for the to get their drilling rigs to???

Sorry for my ignorance,
Eddie

Highbeam · Mar 10, 2006

Even if you went right next to a river and drilled a well, the groundwater would me way below the river. The canyon collects and is formed by water from the surface, not the ground. Our wells here on the valley floor between Mt. Rainier and the puget sound are several hundered feet deep despite our ground elevation of 60 feet above sea level.

They're just two different things.

Phils · Mar 10, 2006

You've been getting some good info already. Some things I can add:

Witching for water does work. My driller didn't believe in them and drilled a totally dry hole at the best place he recommended (atop a small rocky ridge). We've been using the one we had him drill per the witch's recommendation for over 20 years (about a hundred feet away from his dry hole).

We have been off the power grid since we bought in 1977. Our battery bank is charged by solar panels and there is a propane generator for extended foul weather times. I have another gas generator for a backup. Diesel gensets are better (one reason is because it's easy to find ones that run 1800RPM instead of 3600RPM) but I chose propane because it is delivered (hauling gas or diesel is a pain).

Our well is in one building (pumphouse) and the water storage tank is in another (watershed). I use the two pipe system (pvc is cheap). One pipe to the tank from the well. I have a couple of pressure tanks in the watershed that are charged with a 110V jet pump (run from a dedicated inverter), which feeds a second pipe to the house and yard faucets. There is also a 12V pump to charge the tanks as a backup.

I have two other inverters -- one for lights and entertainment, the other for everything else in the house. Using just one inverter for the house caused the TV to "wink" off and back on when the washer or dryer started. All three inverters and the charging aparatus are together with the battery bank in the pumphouse.

The main inverter can be programmed to automatically start and stop the generator according to battery voltages but I prefer to run the gen myself. It's behind the pumphouse maybe a hundred feet from the house and is difficult to hear when it's on. I have remote switches in the house to control it. I also have a digital voltmeter in the kitchen so we can see the state of charge in the batteries easily.

I don't want to bore everybody with a book-long post, so I'll just say that I've worked out my power and water systems to my satisfaction and will gladly pass what I've learned on to you if you want. Either post here (I pretty much keep a TBN window open during working hours, makes sitting on "hold" much better) or PM me.

Phil

stumpfield · Mar 10, 2006

I have the same curiosity as EddieWalker. What the well driller told 3RRL is in direct conflict with what I read on geologist/hydrolygist's paper indicate (published by pennsylvania water resource board). For my specific location, the ravine is a the creek. I can see the granite exposed and surface fractures everywhere. If it were less likely to have fracture below (water flow) because the rocks compress tightly together, then why is all the springs are located in the lower part of the ravine. The springs run year around to feed the lower parts of the creek which flows into the Chowchalla river. During the wet season, I can see water comes out of the rocks in the upper part too. This is weeks after it stops rainning.

I can undertand it's not practical to drill in the middle of a ravine becuase it's difficult to get the drilling rigs there. But how about just on the side of the ravine? Wouldn't it be more favorable than on top of a ridge? or a hilltop? I'm just curious.