How Deep Is My Well? 4 Ways to Find Well Depth and Water Level
The fastest way to find how deep your well is: look up the well log, also called a well completion report. Most states keep these online, and the log lists total depth, casing depth, static water level and often the pump test results.
No paperwork? You can measure the water level and the depth yourself with a weighted tape or a water level meter. I will walk you through both, plus a calculator that turns your readings into how much water is standing in the well.
Boreholeflow is reader supported. When you buy through links on this page, I may earn a commission at no extra cost to you. Read the full disclosure.
| Method | Cost | What you learn |
|---|---|---|
| Your well log or state well database | Free | Total depth, casing, original water level, yield |
| Ask the driller or pump contractor | Free to a service call | Depth, pump setting, history |
| Weighted tape or line | Under $30 | Total depth (shallow and medium wells) |
| Water level meter (sounder) | About $100 to $1,600 | Static and pumping water level |
The USGS puts the median depth of US domestic wells at 142 feet (USGS).
Step 1: Find Your Well Log
In most states, the driller has to file a report when a well is finished. If your well was drilled in the last few decades, there is a good chance a record exists.
Start with your closing papers or the previous owner. If nothing turns up, search your state database by address, owner name or location.
| State | Where to search | Notes |
|---|---|---|
| Minnesota | Minnesota Well Index | Depth, geology, construction and static water level. Mostly wells from 1974 on |
| Texas | TWDB driller reports and the TCEQ viewer | TWDB for wells from 2003, TCEQ for older wells |
| Pennsylvania | PaGWIS via PaGEODE | Hundreds of thousands of well records |
| Wisconsin | DNR Well Records Search | By township and section before 1988, by address or owner after |
For other states, search for your state name plus “well log search” or “water well records”. The state geological survey, health department or environmental agency usually hosts it.
If there is no record, call local well drillers. The firm that drilled your well, or the one that last pulled the pump, often keeps job notes on the depth and pump setting.
Well Depth vs Water Level: Know the Difference
People mix these up all the time, and they answer different questions.
- Total well depth is how far the hole goes down. It does not change much over time.
- Static water level is the depth to water when the pump has been off long enough for the level to settle.
- Pumping water level is the depth to water while the pump runs. It sits lower because pumping draws water down around the well, which the USGS calls a cone of depression (USGS).
- Drawdown is the gap between the two.
A 300 foot well with water standing at 40 feet holds a lot more water than a 300 foot well with water at 250 feet. The water column is what matters for your pump.
Step 2: Measure It Yourself
Nebraska’s state groundwater procedure (SOP GW-072) describes the same methods well professionals use. Here is how they work in plain terms.
Before you start
- Turn off the pump at the breaker and let the water level settle. This can take minutes to hours.
- Remove the well cap carefully and keep everything from falling in. Wiring and the safety rope are right under the cap.
- Clean anything that goes into the water. Use a mild chlorine solution or plan to shock the well afterward.
Measure the water level with an electric tape
Lower the probe slowly until it beeps or lights up. Read the tape at the top of the casing, then subtract the height of the casing above the ground.
Measure the water level with a chalked steel tape
Rub carpenter’s chalk on the end of a steel tape and lower it past the water line. Pull it up, read the wet mark and subtract it from your reading at the casing top.
Measure the total depth with a weighted line
Tie a rounded weight to a measuring tape or marked line and lower it until it goes slack on the bottom. In deep wells the bottom can be hard to feel, so repeat the reading a few times.
Never do this past a submersible pump if you can avoid it. The weight can snag on the drop pipe, wire or torque arrestor, and a lost weight is a real problem.
Sonic meters
A sonic meter sends a sound pulse down the casing and times the echo, so nothing goes into the water. The Eno Scientific Well Sounder 2010 PRO reads from 9 to 2,000 feet and lists at about $1,595. It is a professional tool, but some pump contractors use one on service calls.
Well Water Level and Volume Calculator
Enter your tape reading and casing height to get the static water level. Add the total depth from your well log to see how many feet of water stand in the well and how many gallons that is.
Gallons per foot of casing: 4 inch 0.65, 5 inch 1.02, 6 inch 1.47, 8 inch 2.61 (Kansas State University Extension MF911). Measure with the pump off and the level settled.
Water Level Meters Worth Considering
If you check your well often or live with a weak well, a water level meter pays for itself. These are the types I see on the job.
Solinst Model 102 Water Level Meter (100 ft)
A narrow probe on a flat tape marked in feet. Built for monitoring wells and small casings.
- 100 ft tape
- Audible and light signal at water
- Slim probe
Accurate and durable.
Pricier than consumer meters.
Heron dipper-T2 (200 ft)
A longer tape for wells with deeper water levels.
- 200 ft tape
- Water sensing probe
- Portable reel
Reaches deeper water levels.
More than most shallow wells need.
Heron Water Tape (60 m)
An economical fixed probe meter from a recognized well instrument maker.
- 60 m (about 197 ft) tape
- Fixed probe
- Reel mounted
Lower cost from an established brand.
Fewer features than pro models.
Compare more options in our best water level meters and well sounders guide.
What the Numbers Tell You
Gallons stored in the casing
Every foot of water in a 6 inch casing holds about 1.47 gallons, according to Kansas State University Extension. A 4 inch casing holds 0.65 gallons a foot, and an 8 inch casing 2.61.
So 100 feet of water in a 6 inch well is about 147 gallons in reserve. That is why a low yield well can still supply a morning of showers.
Pump setting
Your pump should sit well below the pumping water level, not just the static level. If your water level is dropping toward the pump in dry months, a dry run protector is cheap insurance. See well pump protection devices.
Shock chlorination
You need the water column and casing size to dose chlorine correctly. Our guide on how to shock a well uses the same gallons per foot figures.
Choosing a pump
Total dynamic head starts with the pumping water level. Plug your numbers into what size well pump do I need, and measure your yield with how to test well flow rate.
Frequently Asked Questions
How do I find out how deep my well is?
Check your well log or well completion report first. Most states have an online well records database you can search by address or owner. If there is no record, ask local drillers or measure it with a weighted line.
How deep is the average residential well in the US?
The USGS puts the median depth of domestic supply wells at 142 feet, based on about 7.6 million records. Many are much deeper or shallower depending on local geology.
What is the static water level of a well?
It is the depth from the ground to the water surface when the pump has been off long enough for the level to recover. It is shallower than the pumping water level.
How many gallons of water are in my well?
Multiply the feet of standing water by the gallons per foot for your casing: 0.65 for 4 inch, 1.02 for 5 inch, 1.47 for 6 inch and 2.61 for 8 inch.
Is it safe to drop a tape measure down my well?
Only with care. Turn off the pump, use a rounded weight that will not snag and clean the tape first. Losing a weight or tape down the well can be costly to retrieve.
Sources (accessed November 2026): USGS well depth study; Nebraska SOP GW-072; K-State Extension MF911; Fondriest; state well databases linked above.
