How to Check the Water Level in a Water Well

Owners of water wells should periodically measure the water-table elevation in their wells.

Manual Water-Level Measurement

Routine water-level monitoring will provide data about natural variations in the groundwater elevation.Routine water-level monitoring will provide data about natural variations in the groundwater elevation.
Water-table measurements will help you determine that the well has the capacity to provide a sufficient quantity of water. A dramatic change in the water-table elevation will signal a problem with the well supply. You can use manual or automatic water-level measurement techniques to gauge the groundwater elevation on a routine basis.

Remove the well cap and allow the well to sit for approximately 20 minutes to equilibrate. If the well has a permanent well pump, make sure that the water-level meter probe will fit into the well. If the probe does not fit, you must either remove the pump or choose to install automatic water-level measurement equipment.

Place a mark with a permanent marker on the casing to establish a reference mark. You will read the water-level depth from this mark each time to provide consistency between readings. This is especially effective for well casings that do not have level surfaces.

Turn on the water-level meter and press the test button to make sure that the equipment is operational. If the model you have does not have a test button, immerse the probe in a glass of water to make sure that it is functioning properly. The meter should emit a tone when it encounters water.

Lower the probe into the well slowly, adjacent to the measurement mark on the casing. When you hear a strong tone, stop lowering the probe. The tone indicates that you have reached the top of the water table.

Read the water-level measurement from the graduated tape that is next to the mark on the top of the casing. Record the measurement in your notebook to the nearest 0.01 foot.

Automatic Water-Level Measurement

Choose an automatic water-level measurement method. Two popular methods are air lines and data loggers with pressure transducers.

Install the automatic water-level measurement equipment at the same time you install the permanent well pump, if possible. You can install the equipment in an established well but it may be more difficult. Follow the manufacturer's instructions for the installation.

Place the data logger or air pressure gauge inside the well cover to protect it from weather and damage. The air pressure gauge will record the water level continuously. You can program the data logger to record the water level at specified intervals. Record the water level data in your notebook.

Things You Will Need

  • Manual electronic water level
  • Automatic water level
  • Notebook


  • There are other types of manual water-level indicators, such as weighted or chalked tapes; however, the electronic meter is often the most accurate. Any method you choose should be able to measure the water level to the nearest 0.01 foot.
  • You can install and remove the pressure transducer and data logger periodically if you do not want to leave it permanently in the well.
  • Measure the water level in your well weekly to gather sufficient data about the natural variation in the water-table elevation.

About the Author

Tracy Barnhart is an earth science expert. A professional geologist with over 16 years of technical writing experience, she has expanded her writing skills to include instructional articles on business, parenting, finance and science. She has Bachelor of Science and Master of Science degrees in geology from Furman University and the University of South Carolina.