How deep are water wells in Karnes County, Texas?
Half of the home water wells drilled in Karnes County in the last 10 years are between 281 and 500 feet deep. The median is 400 feet, based on 263 driller reports filed with the state. Drillers measured the water standing a median 116 feet below the surface (257 wells). That is deeper than the Texas median of 250 feet.
Updated every day from Texas Water Development Board driller reports. Last update: November 10, 2026, using the state file of November 9, 2026. These are depths of real wells drilled nearby, not a promise about any property. Groundwater can change over short distances and with drought. A licensed water well driller can tell you what to expect on a specific tract.
Key figures
- Typical depth (middle half)
- 281 to 500 ft
- Median depth
- 400 feet
- Deepest 10% are past
- 609 feet
- Water level (median)
- 116 feet (257 wells)
- Yield (median)
- 50 gallons per minute (1% pump-tested)
- Wells used
- 263
- Period
- Last 10 years
- Latest report
- September 4, 2026
- Depth rank
- 68 of 245 (1 = deepest)
- Confidence
- Standard
How deep the wells are
Number of home wells by depth, last 10 years (or since 2001 where wells are few).
| Depth (ft) | Wells |
|---|---|
| 50 to 100 | 1 |
| 100 to 150 | 9 |
| 150 to 200 | 15 |
| 200 to 250 | 26 |
| 250 to 300 | 17 |
| 300 to 350 | 38 |
| 350 to 400 | 23 |
| 400 to 450 | 47 |
| 450 to 500 | 19 |
| 500 to 550 | 25 |
| 550 to 600 | 11 |
| 600 to 650 | 13 |
| 650 to 700 | 7 |
| 700 to 750 | 8 |
| 800 to 850 | 1 |
| 850 to 900 | 1 |
| 900 to 950 | 2 |
Median depth by year
Median depth of home wells finished each year. Years with fewer than 10 wells are not shown.
| Year | Median (ft) | Wells |
|---|---|---|
| 2003 | 280 | 30 |
| 2004 | 284 | 14 |
| 2005 | 305 | 25 |
| 2006 | 320 | 27 |
| 2007 | 274 | 22 |
| 2008 | 338 | 23 |
| 2009 | 316 | 24 |
| 2010 | 250 | 12 |
| 2011 | 260 | 31 |
| 2012 | 390 | 37 |
| 2013 | 410 | 54 |
| 2014 | 360 | 49 |
| 2015 | 365 | 33 |
| 2016 | 400 | 18 |
| 2017 | 310 | 30 |
| 2018 | 316 | 15 |
| 2019 | 420 | 21 |
| 2020 | 420 | 16 |
| 2021 | 480 | 28 |
| 2022 | 350 | 42 |
| 2023 | 418 | 42 |
| 2024 | 420 | 39 |
| 2025 | 369 | 20 |
Are wells in Karnes County getting deeper?
New home wells in Karnes County are deeper than 20 years ago: the median went from 292 feet (2003 to 2007) to 400 feet (2021 to 2025), 37% more. The water level measured when each well was finished is also lower: 96 feet then, 120 feet now. Read the 20-year study.
Aquifers under the county
The Texas Water Development Board maps the Gulf Coast, a major aquifer, at the surface (outcrop) across 75% of the county; the Carrizo-Wilcox, a major aquifer, below other rock (subsurface) across 46% of the county; the Yegua-Jackson, a minor aquifer, under 25% of the county.
What a well costs in Karnes County
At the median depth for Karnes County (400 feet), a complete home well (drilling, casing, pump, pressure tank and hookup at the well) would cost roughly $12,500 to $30,500, by TerraFunded's estimate from published Texas prices. Trenching and the line to the house are extra. Get quotes from at least two licensed drillers.
Neighboring counties
- Atascosa County: median 380 ft
- Bee County: median 212 ft
- DeWitt County: median 184 ft
- Goliad County: median 210 ft
- Gonzales County: median 360 ft
- Live Oak County: median 250 ft
- Wilson County: median 380 ft
Common questions
How deep do I need to drill a well in Karnes County?
The middle half of home wells drilled there are 281 to 500 feet deep; one in ten goes past 609 feet. The depth a given tract needs depends on where it is and what layers the driller hits.
How much does a water well cost in Karnes County?
At the median depth (400 feet), a complete well would cost roughly $12,500 to $30,500 by TerraFunded's estimate from published Texas driller prices ($25 to $60 per foot plus pump and equipment). The real price comes from a driller's quote.
How much water does a well produce in Karnes County?
Drillers reported a median of 50 gallons per minute (257 wells). Only 1% of those figures come from a pump test; the rest are the driller's estimate, so treat them as a guide.
Are wells in Karnes County getting deeper?
New home wells in Karnes County are deeper than 20 years ago: the median went from 292 feet (2003 to 2007) to 400 feet (2021 to 2025), 37% more. The water level measured when each well was finished is also lower: 96 feet then, 120 feet now.
How do I see the well report for a property or a neighbor's well?
Every well drilled in Texas since 2001 has a public driller's report. On this page's map, tap a well to open its official report on the state's site, or look it up by location in the TWDB viewer.
How to read these numbers
Figures cover new and replacement domestic (home) wells, from the reports licensed drillers file with the state. Read the full methodology. Download the county table (CSV).
How to cite: TerraFunded Texas Well Atlas, from Texas Water Development Board driller reports (data as of November 9, 2026). https://terrafunded.com/wells
Sources
- Texas Water Development Board, Submitted Driller's Reports database (file of 2026-11-10)
- U.S. Census Bureau, 2024 cartographic boundary file, counties (1:500,000) (file of 2025-04-10)
- Texas Water Development Board, major aquifers (updated December 2006) (file of 2007-01-03)
- Texas Water Development Board, minor aquifers (updated December 2017) (file of 2017-12-15)
- TWDB well report viewer