(206) 949-5683, Top Rated Plumber, Seattle
Results 1 to 6 of 6

Thread: running water out of old well

  1. #1
    DIY Member ugabulldog's Avatar
    Join Date
    Nov 2007
    Location
    Northeast GA
    Posts
    60

    Default running water out of old well

    I have a drilled well, 1hp 12 gpm pump at 240' and let it run from faucet at wellhead, trying to get clear water. It ran dry after after 20 min or so and water was still very dirty. The faucet is definetly putting out more than 12 gal. per min, closer to 20 gpm....is this pumping water too fast, causing dirt or whatever to be pulled into water?? Also, how long is too long to let pump run after water stops pumping, any?? I have to make it about 400' to shut off pump unless someone is there with me. thanks

  2. #2
    DIYer, not in the trades LLigetfa's Avatar
    Join Date
    Feb 2011
    Location
    NW Ontario, Canada
    Posts
    3,679

    Default

    First off, the static height of the water is as important a factor as the depth of the pump. It determines both the storage capacity and the height the pump needs to lift. The storage capacity determines how many gallons you can pull before the well's recovery rate becomes an issue.

    When my mud well was put in, the well driller left his 5 GPM running for days, both to get it to run clear, and to satisfy the mortgage lender that there was adequate GPM of recovery. When I put my 10 GPM pump in the well, it immediately turned muddy and actually sucked mud up into the pump.

    Now, I assume at 240 feet that your well is drilled in rock and that eventually it will run clear. A 12 GPM pump with no pressure (depending on the size of the wellhead faucet) could pump more than 12 GPM but if you are pumping the well dry, that is eventually a column of 240 feet of water the pump needs to lift. With every 2.31 feet equal to 1 PSI, that's around 100 PSI down at the pump. Surely that should regulate the GPM down to something the well can recover from. Did the driller's report state the GPM the well is capable of?

  3. #3
    Moderator valveman's Avatar
    Join Date
    Mar 2006
    Location
    Lubbock, Texas
    Posts
    4,156

    Default

    20 minutes at 20 GPM is 400 gallons stored in the well. That is pretty good. Wait exactly one hour and do it again. Time how long it takes and how much water you get out of the well the second time. Then wait 30 minutes and do it again. The amount of water you get out, divided by the number of minutes it took, will give you a good indication of your recovery rate.

    If you run more water than the recovery rate, you will always pump the well dry. You can try to choke the pump back to the recovery amount and it should run steady as long as you want. However, the recovery flow rate may not be enough to help clean out the well. What you are doing is probably the best way to clean out the well. Run it hard until it pumps off, wait 30 minutes or an hour, and do it again. If you can get to the kill switch within about a minute after the well pumps dry, you won’t hurt the pump. It is still in water and has water in it, so it takes a few minutes to start heating up.

    The slower the recovery rate, the longer it takes to clean up a well. I have a well that makes a little less than 1 GPM. When I shock the well and try to clean it out, it takes many days. I use a Cycle Sensor to shut off the pump when the well is dry. Then I set it to automatically restart in an hour. It pumps out about 50 gallons, is off for an hour, then does it again. After a couple of days it clears up nicely.

  4. #4
    DIYer, not in the trades LLigetfa's Avatar
    Join Date
    Feb 2011
    Location
    NW Ontario, Canada
    Posts
    3,679

    Default

    Quote Originally Posted by valveman View Post
    20 minutes at 20 GPM is 400 gallons stored in the well..
    How many gallons in 240 feet of casing? I guess it depends on casing size and how much the pipe and wiring displaces but I wild-ass-guess around a gallon per foot for a 6 inch casing so either the well recovery is pretty good or the GPM is dropping off as the level drops.

  5. #5
    DIY Member ugabulldog's Avatar
    Join Date
    Nov 2007
    Location
    Northeast GA
    Posts
    60

    Default

    it was running clear a couple of days ago,....I am just wondering if there could be another reason for the dirtyness in water today?? I shocked well a couple of days ago also.

  6. #6
    That's all folks! Gary Slusser's Avatar
    Join Date
    Aug 2004
    Location
    Wherever I park the motorhome.
    Posts
    6,790

    Default

    6" has 1.47 gals/ft of water and yes, the lower the water level goes the less gpm the pump will deliver.
    Gary Slusser Retired (= out of business)
    Click Here to learn how to correctly size or program a water softener.
    CAUTION, as of Nov 12 2013 all YouTube videos showing how to rebuild a Clack valve have an error in them that can cause damage.

Similar Threads

  1. water running when nothing is on
    By crazebstrd in forum Plumbing Forum, Professional & DIY Advice, Tips & Tricks
    Replies: 20
    Last Post: 12-03-2009, 05:17 AM
  2. Why am I running out of hot water??
    By rhliberman in forum Plumbing Forum, Professional & DIY Advice, Tips & Tricks
    Replies: 22
    Last Post: 01-31-2008, 06:47 AM
  3. No running water
    By tgaf1949 in forum Plumbing Forum, Professional & DIY Advice, Tips & Tricks
    Replies: 4
    Last Post: 01-23-2008, 02:02 PM
  4. Running out of water
    By Ken P in forum Pumps and Tanks Well Forum & Blog
    Replies: 1
    Last Post: 03-17-2006, 10:10 AM
  5. can hear water running when neighbors water lawn
    By brendis in forum Plumbing Forum, Professional & DIY Advice, Tips & Tricks
    Replies: 2
    Last Post: 08-22-2005, 05:08 PM

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •