Re: water well depth

From: Joerg (notthisjoergsch_at_removethispacbell.net)
Date: 01/29/05 

Date: Sat, 29 Jan 2005 19:24:09 GMT

Hi Steve,

>The next time I have the "really expensive well riggers" out, I could
>ask them to drop something into the well. Is a simple wire enough? If
>you have a wire with a heavy weight on it (to get it to the bottom)
>can you tell the distance to the water? I don't like the usual
>suggestions as "drop a pebble" or "make an ultrasound pulse" or "blow
>through a straw into the well bottom". I don't dislike them because
>they are not possible, just they are not sustainable (dropping
>1,000,000 pebbles fills the well) or "automate able" or just custom to
>one particular well construction technique.
>
>

Well, the echo method would be sustainable and long-lived. Pretty much
maintenance free if you use good parts that don't corrode easily. Some
of our early ultrasound designs are still in use, to the point where the
chassis paint starts to wear off.

An idea for the cable: What if you mounted a pressure transducer at the
end? Then you would exactly know where your water level is, including
dynamics such as detecting a slow-down of refill through the rock
formation fissures. Of course, you would have to have a non-fatigue and
chemically neutral guide wire in parallel so your cable doesn't sag over
time. And nothing that can leach out and contaminate your water. You
might be able to lower it all the way to the pump if that's safe.

Regards, Joerg

http://www.analogconsultants.com

Relevant Pages

  • Re: Signals on a single wire
    ... > Is the second "wire" a path between you and the negative via your ... If we think of a short piece of water pipe, ... Then if we start the pump it will pump the water in one direction, ... The antenna converts electric signals into electromagnetic waves which ...
    (sci.electronics.basics)
  • Re: Yacht Rf ground and radials
    ... I think we all would be interested in how a small piece of metal buried in sea water can provide an efficient ground versus one or 2 elevated radials. ... Not any more efficient than a foot long uninsulated wire extending downward from the surface. ...
    (rec.radio.amateur.antenna)
  • Re: Yacht Rf ground and radials
    ... The relative velocity of propagation along a wire immersed in water is ... The greater the cross-sectional area, the better, of course, but it would seem not to be a critical factor based on what both Roy and Reg reported, A one inch diameter copper pipe would probably give you some margin based on those reports. ...
    (rec.radio.amateur.antenna)
  • Re: Yacht Rf ground and radials
    ... The relative velocity of propagation along a wire immersed in water is ... I also made some kitchen table-top saltwater measurements about a year ago, but at much lower frequencies than you discuss. ...
    (rec.radio.amateur.antenna)
  • Re: Yacht Rf ground and radials
    ... I think we all would be interested in how a small piece of metal buried in sea water can provide an efficient ground versus one or 2 elevated radials. ... Since the salinity of salt water is not constant using one or 2 radials on yacht would be more efficient. ... Not any more efficient than a foot long uninsulated wire extending downward from the surface. ...
    (rec.radio.amateur.antenna)