In our classes, several people have asked how to get water out of their well when the grid power is off. The answer is, “That depends!” To start, see our article on alternative well pumps.
If your well is shallow, say, less than 25 feet from surface to the water, then you could use a shallow hand pump with a pipe or tube that reaches down to the water level. The pumping cylinder is actually at the top of the well, and it draws a vacuum to pull water up the drop pipe. These are called shallow well pumps or pitcher pumps. They are simple and less costly.
If your well has water more than about 25 feet from the surface, then no amount of vacuum in a pipe will draw the water to the surface. The pump cylinder has to be below the water surface in the well. The pump then pushes the water up to the surface. These are called deep well pumps. They are more costly because there is a rod connected from the surface to the pump, and that is more expensive in terms of materials.
It matters not whether the pump is motorized. The depth of the well to the water determines whether the pump cylinder can be at ground level, or has to be under water.
So, how deep is your well, from the well head to the water? You can use a simple sonar range finding technique to estimate the depth. Here’s what to do.
This requires some mechanical skill, so if you don’t know how to use a wrench, get a plumber or other qualified professional to help. It’s not brain surgery, but you don’t want to mess up your well head or drop anything down your well. PROCEED AT YOUR OWN RISK. We are not responsible for any damage you do to your well system.
First, unbolt the cap on the well. On modern well caps, there are several bolts around the periphery which must be removed. Then the top of the well cap may be removed, exposing the open well casing, which may be plastic or steel. You may need a helper to hold the top of the well cap as it usually carries the electrical cable for the well pump. BE CAREFUL NOT TO DROP ANYTHING DOWN THE WELL!
Now that the well is open, you can gently tap on the outside of the well casing with an implement, or clap your hands over the opening. Be careful because the edge of the well casing might be sharp. You will hear a repeating echo, and the timing of each echo is related to the depth of the well as the sound wave moves down the casing, bounces off the water surface, and moves back up the pipe. The deeper the well, the longer the echo. The sound actually bounces off the open end of the well casing at the top, and moves back down, creating the multiple echo effect!
We have created several sound clips that approximate what you will hear for various depths. They appear below. Click on them and listen to get an idea of what the echo sounds like.
13 feet (fastest echo)
250 feet (slowest echo)
Compare the sounds of these clips with the sound you hear from your well. If you have a smartphone, you could even listen to the clips while at your well head. BE CAREFUL NOT TO DROP YOUR PHONE DOWN THE WELL!
Or your could use an audio recorder app on your phone to record the sound of the well and compare it to these clips when you are at your desktop computer.
Either way, by comparing the sound of the echo of your well to these few sound clips, you can get an idea of how deep your well is.
Be sure you securely bolt the cap back onto your well. Take care not to let any debris fall down the hole. This is a good time to inspect for damage, wear, frayed wires, insect encroachment, etc. If you see anything suspicious, consult a well professional.
If you are technically inclined, then you can take the recorded echo and load it into a sound analysis program like Audacity. Measure the time between two echos and use this formula:
- Depth in feet = echo time in seconds * 560
Using Audacity (which is free), you can load the audio file, highlight the space between echos, and read the Selection Length out of the box at the bottom of the screen.
For example, an echo length of 0.088 seconds results in a depth of
- 0.088 * 560 = 49ft.
Either way, you can get a good idea of the depth of your well, from the well head to the water line. This method does not tell you how deep the well casing is, or the well pump, but generally wells are drilled quite a bit deeper than the water level.
Measure the water depth during various times of the year to get a feel for the variation. Some wells may vary a lot, some little.