Well yield / rate of recovery questions

Discussion in 'Pumps and Tanks Well Forum & Blog' started by gsaunders, Apr 13, 2011.

  1. gsaunders

    gsaunders New Member

    Messages:
    16
    Location:
    Virginia
    1) Let's say you are digging a "new" well. How does a well digger test the yield or rate of recovery of the well with the new well. One wouldn't have a pump yet... so does he have a pump on the rig?

    2) Let's say you are digging an "existing" low yield well deeper. How does a well digger test the yield of the well. I know he can use one's existing pump, but if it is just a 6GPM pump and the water isn't going down then how would he tell exactly what the yield is? pump on his rig?
  2. gsaunders

    gsaunders New Member

    Messages:
    16
    Location:
    Virginia
    I talked to one of the well guys in town and he said they have pumps with them in either case to test the yield.
  3. valveman

    valveman Moderator Staff Member

    Messages:
    4,383
    Location:
    Lubbock, Texas
    In our area, we can’t drill an old well deeper. If it needs to be deeper, we just drill a new well. Well drillers can blow a well with air to get an idea of the flow rate. But you really need a pump to get more accurate. A 6 GPM, ½ HP will still pump 5 GPM from 200’, just not with any pressure. Which is OK to test a well with, so I don’t know why they would need a larger pump to test for less than 5 GPM down to 200’.

    I would want a ¾ HP, 5 or 6 GPM pump, so I could get 5 GPM with good pressure as the water level dropped to 200’ deep. You have more than a couple hundred gallons stored in that well between 40’ and 200’. Just need a ¾ HP to get it from 200’ with pressure.

    If you go with a storage tank, the ½ HP would be plenty large enough. But I would try to use the well depth for storage and set the ¾ HP as deep as possible.

    That is not a bad price for a pump. There are a lot of expenses in well and pump work. 200% markup doesn’t mean he makes that much profit. Even charging that much, at the end of the year he may only end up with maybe 10% profit.

    Well and pump guys get angry and want to be “done” when the customer wants the impossible done at the cheapest price. They can’t will your well to make more water. Even drilling deeper doesn’t guarantee anything. You have what you have, and if that is not enough you need to use a storage tank.
  4. gsaunders

    gsaunders New Member

    Messages:
    16
    Location:
    Virginia
    This particular post was specifically about how do well drillers / pump guys determine the rate of recovery of the well when drilling a new well or drilling an existing one deeper. I wanted to understand whether they have pumps on board to do this sort of testing. And I found that they do... or at least the ones around here. Just trying to gain more knowledge of the practices and processes.

    My guess your response above may be referencing back to my other post where I was having some problems with the pump guy.

    I certainly haven't asked for the impossible and certainly didn't ask for the cheapest price. Although I can image some folks do. I fully understand matters could be made worse by drilling deeper... or even destroying the well.

    But I do expect honest, integrity, and communication. Which I have found little to none in my situation from previous post.

    This is a big learning lesson for me. I almost always become knowledge expert in any project I hire out a third party company to do... so I am well educated and can ask the important questions to be sure everything is on track. In this once case I made a BIG mistake in not doing that before hiring out a company so I am paying for it in multiple ways.

    Thanks for your feedback... and thanks for pointing out somewhere the Cycle Stop Valves. I will be definitely checking into this.

    G
    Last edited: Apr 15, 2011
  5. valveman

    valveman Moderator Staff Member

    Messages:
    4,383
    Location:
    Lubbock, Texas
    I read an article a while back, I think it was in the Water Well Journal. It said pump and well people where notoriously stubborn and hard headed. It went on to say that is because they work in all kinds of bad weather, with heavy and dangerous equipment, and for people who are already mad because they are out of water.

    They should be honest and have integrity, but they maybe slow to call back because they are always dealing with angry customers.

    Testing the well means running the pump at low pressure and high volume until the well pumps dry. Measuring how much water you get out the first time gives you the storage capacity of the well. Then wait a certain time period like exactly one hour, measure how much you get out before the well pumps dry again. How much you get out the second time, divided by the hour or time the pump was off, gives the recovery rate. IE; If you get 100 gallons after the pump has been off for 1 hour, you have 1.66 GPM recovery rate.
Similar Threads: yield rate
Forum Title Date
Pumps and Tanks Well Forum & Blog Low Yield Well - Help! Oct 8, 2013
Pumps and Tanks Well Forum & Blog Setup evaluation for low yield deep well Mar 7, 2013
Pumps and Tanks Well Forum & Blog How do I find instructions/diagrams on low yield well water storage install Sep 27, 2012
Pumps and Tanks Well Forum & Blog ~*~* New well yielding plenty of problems and dirty water that will not clear. ~*~* Jul 26, 2012
Pumps and Tanks Well Forum & Blog Pump Controller is "weak", yields low pressure Mar 30, 2012

Share This Page