Replacing deep well with a deeper well

[The Reverend Natural Light]

I'm thinking about having a new well drilled to replace my old muddy well. The old one is 6" drilled with the pump at 70'. I think the casing is cracked or something. It's almost 40 years old. Any way, I'm tired of fighting it.

Driller says they'll put in a new one for about $2500, 275' deep, PVC cased to 100' with 50' grout. Sounds like a good deal and the company is well known in the area.

Questions:

1. I set the pump in the old well by myself. How much harder is it going to be to set a pump that much deeper? The pump, 70' of plastic pipe, and T handle was damn heavy, but manageable. When I've fed 250+ feet of pipe down the new hole, am I going to be in big trouble trying to hold on?

1. Is 1" poly pipe and a normal pitless adapter suitable for the load? Will PVC casing hold the pitless adapter?

2. The pump in the old well is almost new. Can I reuse it? No idea what size it is. What's the norm for a well that deep? The head will probably be about 75' away and 20' uphill from the house.

1. Is there a legal way to splice wire underground? The pipe and wire to the house are new and I'd like to reuse them as much as possible. It runs under a concrete patio.

Thanks!

[M Q]

That sounds like a good price to me: less than $10/foot. You must live in a different area than I do. I paid about $25/foot for a similar depth well.

I think that you want to use some sort of winch. You are now adding both an extra 200' of plastic and an extra 200' of copper (real heavy). While you could construct the apparatus to do it yourself, there are plenty of pump & well guys with just the appropriate truck for that. Ask your driller for recommendations or check the yellow pages.

Don't know -- I have 1" sched 80 for a 300' deep pump.

Yes, you can reuse the pump. Because of the extra 200' of wire, you may need to go to a larger gauge wire. The pump controller (starter cap and relay) should have some specs on it. Also if it is almost new, I assume that you must have documentation. When figuring wire size you have to consider the entire distance from the breaker to the well head and down to the pump.

Yes, but only with appropriate materials and methods. Also do the wire size calculations as mentioned above.

[Speedy Jim]

Not the well expert, but we'll get discussion going.

For your present 70Ft well, you likely have a 1/2 HP (maybe 3/4 HP) pump. Going down to 250/275 Ft, you will need a 1 1/2 HP, maybe 2 HP. You better have a pump dealer analyze the specific needs.

Making that big a jump in HP probably means that the wiring and the branch circuit breaker won't handle the load. Also the question of whether the pumps are 2-wire or 3-wire.

If 70 Ft of pipe was tough to handle, 275 Ft will be 3 X harder. Have a pro install it. A pitless adapter should be able to handle the weight.

Still want to give up your old well? :-)

Jim

[M Q]

...

I don't agree here. There should be no additional head for a deeper pump, as the water table will be at the same depth. There will be some slight additional friction on the additional pipe, but that is probably not significant. Just as a data point, when I went from a 180' foot well to a 320' well, I kept my

3/4 HP 7 gpm (nominal) Gould pump. The water table is about 200-220' below the well head and it pumps into a tank that is about 100' above the well head. I get about 5 gpm into the tank. The depth that the pump is set does not matter, as long as it is not sucking air.

I agree here that some professional assistance may be useful.

...

[Speedy Jim]

Yes, you're correct, of course. That's if the water table is the same and he is merely placing the pump under a 200 Ft head of water in the well.

More reason to get local advice before jumping in.

[dpb]

...

But the intake and discharge _from the pump_ will be at the lower level so there is additional head -- the length of pipe from the former elevation to the new.

[Doug Miller]

and hence under a correspondingly higher pressure

which the higher pressure at the pump exactly makes up for.

At least that's the way it looks to me.

[dpb]

Yeah, actually, come to think of it, I guess that's a wash...

[Harry K]

Pretty much so except there would be a bit of inertia added due to starting a longer colume of water moving at each pump start. Doubt it would be significant though.

Harry K

[dpb]

Yes, the differences are second order -- for some reason I thought of the exit but not the entrance height initially...just an oversight, DOH! moment... :(

--

[Vic Dura]

On Wed, 25 Jul 2007 18:41:29 -0500, dpb wrote Re Re: Replacing deep well with a deeper well:

The additional head-loss will be about 3.2 ft (1.4 psi) for the flow through an additional 200' of 1" pipe. See

[The Reverend Natural Light]

Actually, it'll be a little more than I posted. The driller said $2500 ballpark for a 275 foot, but when I itemize everything with additional casing and grouting, it'll be about $3100 (dense neighborhood with lots of drainfields - I want a lot of casing). It's still not too bad a price.

I hadn't thought about the wire. That alone will be a lot of weight. I could build a frame to sit over the well with a truck wheel or something as a roller, then attach the free end of the pipe to my jeep and lower it that way. Probably safer. I'd hire a pro, but the drilling and parts alone are about all I can afford for this and I enjoy working on things. If it takes a week to weld up a rig to hold the pipe then it'll be fun.

PVC or the flexible stuff (polyethylene?) ?

The pump, tank, switch, pipes, and wires were all replaced just before I bought the place. Unfortunately, I don't have any documentation. The wire to the existing pump is 10 gauge three conductor, although only two conductors are used. Depending on where the health department tells me to drill, there'll be 250 feet more pipe and wire than before.

Thanks for the advice!

[The Reverend Natural Light]

It's a Gould pump but I didn't get any numbers off it when I had it out last. The breaker is a 60 amp (I think). Wire is 10 gauge (I think - but it is larger than 12 gauge), 3 conductor to the well head, and 2 conductor down the drop pipe. The ground wire doesn't connect to anything past the well head.

Where's the fun in that?

The local plumbing supply place only sells one type of pitless adapter and locals wells around here are normally 300 feet. Still, it just seems like a whole lot can go wrong if that little brass part breaks.

It has to get fixed. I go through a pair of water filters every week or so. Now I'm getting married. She and the future step daughter aren't going to be as adapted to coliform bacteria as I am. It's truly amazing that the most important parts of a house are where the water comes from and where it goes when you're done with it.

[hallerb]

leave old well in place for watering garden washing cars etc. since its so shallow you can use it safely without endangering new well. more people more water use.

just replace everything for berst longest lifed least hassles.

your spending 3 grand might as well spend a little more so you can forget about this for awhile.

existing pump may be worn from passing so much dirt, longer run requires heavier power cable to avoid voltage drop.

by patching it in its like buying a new car but putting in engine from old one:(

[boing]

Get an old kids swing set frame. Of course I mean a solid steel pipe frame, not the new cheap ones.

They used to make a clamp that would go around the steel pipes so you could lower or raise the pipe, stop to reconnect a winch cable, and continue on, but I dont know if that sort of thing would work with plastic pipe. Of it does, you can use a skid loader or tractor with a loader, but you only move the pipe about 10 feet at a time, then clamp the pipe and move the cable to another place. I saw a guy doing this once, but he had steel pipe. (just think how much 275 feet or steel pipe weighs ....

[M Q]

...

60 amp breaker w/ 10 guage wire doesn't make sense (or code). If it was 3 wires down to the pump, there should be a rectangular "control" box somewhere that has pump motor data on it (such as HP).

If it is a 2-wire pump, you could measure the run current (if you have one of those clamp-on ammeters) and get an idea from that: For 230 V, two wire Franklin motors (used in Goulds pumps):

1/3 HP 4.0 Amps 1/2 HP 5.0 Amps 3/4 HP 6.8 Amps 1 HP 8.2 Amps 1 1/2 HP 10.6 Amps (from You may want to look up documentation on Goulds 4" Submersible pumps here:

[M Q]

PVC -- 20' sections. Installed by one of those "pump guys" with those trucks. The winch had a high point that was more than 20' above the ground. The end of the winch cable had a swivel union on something with 1" MPT that could thread into the end of the pipe. He had a flat piece of steel that would go over the well casing and had a slot in it that would go over the pipe, but not the coupling at the end of the pipe.

[Reinhard]

A couple of points;

1. if the old well is getting mud or whatever in it then the same stuff will get into your new well unless the old well is properly abandoned. You can get the procedures from your state groundwater agency. Most states have laws about abandoning wells properly - a poorly abandoned well can pollute an aquifer so you and your neigbours will all have problems.You could spend all that money and be no further ahead and then get into trouble with the state on top of everything. A good, registered well driller should know all this and have included it in his quote but I would bet he didn't include it or intend to do it. In my experience the vast majority of well drillers are very poorly educated in their field. In my area I've asked local engineers and government groundwater specialists which driller they would recommend and they all said "none of them, except maybe the one who is most expensive by far." He is most expensive because he is the only one doing it right - the rest all are busy but are getting by only on luck and the fact that consumers have too much trouble suing them out of business. I don't think this situation varies from state to state.

1. The whole issue of the pump has not addressed the basic hydraulics - pumps are hardly ever installed near the bottom of a well. The pump needs to be only deep enough that it has sufficient submergence at maximum drawdown. Drawdown is how far the water in the well drops when the pump has been running for a while. How long depends on the capacity of the well and/or the groundwater formation. You could get some idea of this by measuring the distance down to the water surface while the pump is running - write down the measurement and the time, leave pump running for another 10 minutes and re-measure, keep re-measuring every 10 minutes until the level doesn't change. The flow should be at or better yet, above the maximum flow you intend to draw from the well. You should install the pump below this level plus a safety factor of about 10 or 20 feet. The safety factor ensures that the pump will never run dry so you need to know if the groundwater levels change from year to year or season to season and make sure the pump is below the lowest possible depth. That is as low as you need to go and it should be no where near the bottom of the well. There is a special well logging tape that has two wires in it and a fitting on the end with two exposed contacts. When the contacts hit water it beeps and you pull it up and down a bit until you know exactly what measurement causes the beeping to start. Be careful not to get this tape caught between the pitless adaptor and the well casing - took me quite a while to get it loose. Alternatively, you can gamble that the new well has exactly the same level as the old one and set the pump at the same level in the new well. The well driller should do this pump test for you before he leaves - don't pay him until he has done it.

2. Pump size depends on the lift from the water level in the well plus all the hydraulic losses in the piping. It is most likely that the level in the well will be the same as the old well and since ou are re-using the old pump the flows and losses will not change. Therefore you can re- use the old pump. You may get some improvement in pressure if you go up one size in the pipe from the pump to the pitless adaptor.

1. Something I learned the hard way - wells can very easily get infected by iron bacteria. Iron bacteria is everywhere on the ground. It gets into wells by transfer from the well drilling equipment or from drill equipment touching the ground and being put into the well. Even installing the pump can infect the well because you have to lay out the pump and pipe on the ground while you work. The driller is supposed to disinfect all of his equipment between jobs but almost none of them do. In addition, the driller is supposed to use chlorinated water for mixing his drilling mud - smell the water truck for chlorine odor, if none add enough Javex to get around 200 parts per million chlorine concentration. When the job is done, pump installed, etc, add a jug of javex to the well and leave it for at least an hour, 24 hours is best. Then run pump until there is no more smell of chlorine. At a few dollars for the Javex, this is cheap insurance to avoid a lot of future hassle.

2. The advice to get some professional advice was very good - take it or be sorry. Most well troubles began while the well was being drilled or planned. Try to be there while the driller is working, measure all drill sizes, pipe sizes, pipe lengths, etc. Figure ou how to tell how deep the drill is - there are marks on the rig and you can measure the length of the drill rods. Then just count how many rods on the truck before he starts aand then keep count of how many are down the hole and use the rig mark to get a close part-rod measurement. If you don't track the depth yourself there is no way to tell how deep the well really is or to sue of you ever feel it was not drilled as deep as promised. The odds of getting a 375 foot deep well if you are not there are slim to none but you will sure get charged for 375 feet, probably more.

1. Well drillers are notorious for padding bills with extras - grouting is supposed to be included but they'll try for an extra for cementing and tell you it is something different - one is around the casing between it qand the hole and the other is at the end of the casing. Don't fall for it - both are art of drilling a well and should have been part of quote, period. Then there is the famous "my bit broke and you as owner of the well are responsible for it's cost, maybe ,000, my guy tried for ,000. This is malarkey - he broke it not me. If the carpenter broke his hammer I sure wouldn't replace it. When they try this one they usually have put an old worn-out bit in the hole and are just getting a poor home owner to buy them a new one. If you don't track the well depth during the drilling you may get the old "we didn't get enough water at 375 feet so we had to go deeper at per foot".

2. The driller is supposed to develope the well when he is done - this can mean a lot of different things depending on the type of rock drilled, the type of well (cased, screened, etc). At a minimum he should pump out at a rate of double your intended pump capacity for at least an hour. This cleans out the well and proves that it can deliver the required capacity. Capacity and drawdown are related so he has to take 10 minute level measurements while he is pumping. All this info is supposed to be recorded and one copy left with you and one sent to the state for their records. It's a requirement of all wells drilled.

1. After you discuss all this with the driller you will get a revised estimate to account for all your 'extra' requirements which he didn't include in his original quote even though all of them are standard requirements for all state groundwater agencies and thus shold have been included unless he was planning a sub-standard job. Your final cost will be closer to what another poster said he had experienced and his price was half of what our only good driller charges.

[fartblanket]

Just remember, the deepest well that can be drilled is 41,851,444 feet and 8 inches. After that you penetrate the other side of the earth.