Driving a well point?

zmoz · May 21, 2010

Dumb question from a city boy. Recently our city water bill has gone through the roof, in fact, I believe we pay the most in the country. We're talking ~$200/month for water/sewer. They bill the sewer based on the water I use...without taking into account how much of that ends up on the lawn, and not in the sewer.

Anyway, that means my lawn will be brown this summer unless I can come up with something else. I was thinking about trying to drive a well point like this:
Watersource Stainless Steel Well Point  For 1 1/4in. Pipe, Model# WP3680 | Well Points | Northern Tool + Equipment
to use purely for irrigation. From what I've been able to read about other wells in the area, the ground water level is about 20-25' in this area with clay soil.

Can I honestly pound this thing into the ground about 30' and expect to suck water out of it? That just seems too easy. If that's the case I don't know why I've been putting fancy city water on my lawn all these years! Do you just use regular galvanized pipe? I guess if I accidently hit a rock, I'm pretty much screwed and have to start over somewhere else?

bp fick · May 21, 2010

I don't know your area, but driving points are typically successful in sand/gravel area. Driving through clay is likely impossible.

The reason this works is that a thick layer of sand, 20-25 feet, with a harder pan at that point traps and hold ground water. It isn't particularly potable and usually is polluted with high levels of nitrates, which is a serious chemical to be avoided, especially concerning developing children and babies.

But for irrigation of lawns, it is about perfect. You are re-cycling the ground water over and over, although losing some to evaporation.

I have driven wells as deep as 75', although I don't encourage it. It is hard work. I use driving coupling and a widow maker; heavy weighted pipe with two handles. Using a post hole digger to pilot the first 3 feet is a blessing.

Ask around with old time neighbors. See if anyone has done a driven well in your area first. In clay areas with high water tables, a dug well with crocks works well. Best regards.

bp fick · May 21, 2010

Ask your water department about a double meter. Many municipalities allow the installation of a second meter, just for the exterior irrigation. This saves you the sewer computation on that portion. You should also know that this isn't a cheap install, typically $500-700, which means your payback is way out there, 5 years or more.

The reason sand/gravel areas (with a ground water catch layer of harder pan down 25-30 feet) can produce water is that this sand/gravel top layer allows the ground water to quickly flow to the driven well point. BTW, those points are typically called "sand points". If the subsoil is not porous, the ground water cannot flow fast enough to the point to provide any meaningful pump rate.

zmoz · May 21, 2010

bp fick said:
The reason sand/gravel areas (with a ground water catch layer of harder pan down 25-30 feet) can produce water is that this sand/gravel top layer allows the ground water to quickly flow to the driven well point. BTW, those points are typically called "sand points". If the subsoil is not porous, the ground water cannot flow fast enough to the point to provide any meaningful pump rate.

That makes sense...but how do I know what's 30 feet underground? There aren't really any wells around here since 90% of the houses were built within the last 15 years and they're all on city water. I found an online listing of all the wells in the area with the ground water level at each, there aren't any real close to me but they're all in the 20-30' range.

All I know about the soil really is that it's clay, followed by harder clay for the first 8 feet or so. That's the deepest I've ever dug down. But if the water table is at 20-30', wouldn't that mean there must be some sand/gravel in that area?

Even if I could get a really low flowing well I would be happy. I have a ~2000 gallon pond I could use as a storage tank and pull water from the well constantly.

I'm not sure I'm even "allowed" to have a water well where I live, but I don't plan on asking anyone's permission if I can do it myself.

The water department is totally raping us, they can't come up with a good reason why, and EVERYBODY is outraged. I like the idea of a second irrigation meter if they offer one, but around here I would guess the connection fee is extremely high.

LittleBlueTractor · May 21, 2010

I've been thinking of trying to drive a well for some time now, but need to find enough time to give it a try. Really wanted to do it before it got too hot, but missed that opportunity and now I'll be sweating up a storm unless I wait until the fall -- south Texas is already in the 90s. Anyway, I found this site when doing my research for the project:

Water Well Helpline

Lot's of information for the DIYer out there. Good luck with yours and I'll try to post something if I ever get around to doing anything.

yomax4 · May 21, 2010

I put in a sand point some years back. It really needs to be put down in sand. I used an old used point to get down most of the way. Then I used my loader to pull it out and installed a nice new Stainless point. Gently pounded it back down. Worked fantastic and the water tests great every year. Here is a tip. You have to screw several pipes together to get down 20-30', When you get the point all the way down. Insert a length of inexpensive plastic pipe down inside the pipe to the point. This eliminates leaks and corrosion. Then you must have a check valve on your pump and hook right to the plastic pipe. Make sure you buy a pump that will pump the depth you have set your point. I have used this at my cabin for years.

bp fick · May 21, 2010

Before you begin, you really, really, really need to interview old timers in the area. If no one has ever had a driven well in the area, there's likely a good reason. The old time local hardware guy likely knows too, because if there are driven wells, he has sold them points, drive couplings, 1 1/4 pipe in 6' length to drive down, the driving cap, (goes on top to protect pipe threads, then gets replace by coupling, next section added, driving cap goes on top and the process starts again) and other hardware. That guy has also sold them shallow well jet pumps, check valves and tanks. If none of this stuff is being sold in your area, that's a pretty good indicator that it isn't a locale that will make a good candidate. The whole set up is around $600 minimum.

Sandy areas, around lakes and ponds, cottages "up north" fit the bill. An area with clay on the surface, just isn't fit for driving a shallow well.

Again, you don't give your area, so there's isn't much more help one can give.

jbooth · May 21, 2010

You might try digging down about 8-10 ft. with one of the old twist augers to see what you find. I used to put cased wells in by digging down with an auger till I hit sand and then used a sand bailer to go on down. Put one well down around 50 ft. We used an 8" auger to allow clearance for a 6" casing but you could get by with a lot smaller one. Most of the twist augers had 3/4" inch pipe as the shaft and you would need to aquire pipe extensions for your auger. Was a bit labor intensive but so is hammering a point down. You might also contact some well drillers in the area for a bit of geology education. Noticed in your post you were aware of the geology for the 1st 8 ft or so, so you might need to auger a bit farther than 8-10 ft.

The Dougster · May 21, 2010

Since the OP did not identify just where in the Nation he lives, and since everyone is on a public supply system, it's my guess that a point driven well might be futile.
First and foremost, check the local geology... does your State have a DNR agency? Where do well drillers send their drillers logs? To assume there is available water a few feet below land surface is quite a stretch... research your project before doing anything.