# Well grid 78-21, Texas — Atascosa, McMullen — how deep, and through what

> 173 well reports in Texas state well grid 78-21, covering Atascosa, McMullen. Median depth 40 ft.

## Texas well grid 78-21

A 7.5-minute quadrangle of the Texas state well grid, mostly in [Atascosa County](/county/atascosa.md) and [McMullen County](/county/mcmullen.md). **173** reports, median depth **40 ft**.

### What you will drill through in grid 78-21

*Logged in state well grid 78-21, by depth. The figure is how many wells hit it.*

| Depth, ft | What was logged there |
|---|---|
| 0–25 ft | **Lean Clay** 12 , **Clay** 14 , **Clayey Sand** 11 , **Top Soil** 12 , **Silty Clay** 7 , **No Recovery** 4 |
| 25–50 ft | **Lean Clay** 13 , **Clayey Sand** 10 , **Green Clay** 6 , **Fat Clay** 5 , **No Recovery** 3 , **Poorly Graded Sand** 5 |
| 50–100 ft | **Clayey Sand** 8 , **Lean Clay** 9 , **Poorly Graded Sand With Clay** 8 , **Poorly Graded Sand With Silt** 5 , **Fat Clay** 6 , **Clay** 5 |
| 100–200 ft | **Lignite** 5 , **Sand** 4 , **Clayey Sand** 3 , **Sand (Very Fine Grain), Loose, Wet, Dark Greenish Gray (Gley** 1 , **Sand (Very Fine Grain), Silty, Slightly Clayey, Dense, Light** 1 , **Clayey Sand Very Dark Greenish Gray** 1 |
| 200–300 ft | **Sandy Shale** 2 , **Sand** 2 , **Gray Clay** 2 , **Sand & Gray Clay** 2 , **Shale And Rocks** 1 , **Sand; Olive Yellow To Light Greenish Gray** 1 |
| 300–500 ft | **Sand** 5 , **Gray Clay** 3 , **Gray Shale** 2 , **Clay** 2 , **Sandy Clay** 2 , **Sand & Clay** 1 |
| 500–1000 ft | **Sand** 6 , **Clay** 2 , **Shale** 2 , **Sandy Shale** 2 , **Sand & Shale** 2 , **Clay (Grey)** 2 |
| 1000–5000 ft | **Shale** 8 , **Sand** 9 , **Sand & Shale** 4 , **Gray Shale** 3 , **Carrizo Sand** 2 , **Sandy Shale** 2 |

### Who drills here

*Licensed firms in state well grid 78-21, busiest first.*

| Firm of record | Wells | Median depth, ft | Median yield, gpm | Years |
|---|---|---|---|---|
| [Vortex Drilling Partners, LP](/driller/vortex-drilling-partners-lp.md) | 58 | 13 | — | 2020 |
| [Vortex Drilling, Inc.](/driller/vortex-drilling-inc.md) | 31 | 20 | — | 2006–2023 |
| [Cascade Drilling](/driller/cascade-drilling.md) | 27 | 66 | — | 2016–2019 |
| [Geoprojects International, Inc.](/driller/geoprojects-international-inc.md) | 13 | 34 | — | 2003–2020 |
| [Water Well Services, Inc.](/driller/water-well-services-inc.md) | 10 | 2,780 | 635 | 2009–2016 |
| [TWF Drilling, LLC](/driller/twf-drilling-llc.md) | 7 | 30 | — | 2003 |
| [EnviroCore, Inc.](/driller/envirocore-inc.md) | 4 | 102 | — | 2013–2017 |
| [Tolunay-Wong Engineers,Inc](/driller/tolunay-wong-engineers-inc.md) | 4 | 50 | — | 2015 |
| Premium Well Drilling | 3 | 1,030 | 450 | 2003 |
| [Mhc x-ploration corp](/driller/mhc-x-ploration-corp.md) | 2 | 100 | — | 2016–2025 |
| [Thomas Moy and Sons](/driller/thomas-moy-and-sons.md) | 2 | 460 | 60 | 2008–2017 |
| [Unison Drilling Inc](/driller/unison-drilling-inc.md) | 2 | 4,155 | 300 | 2011 |
| Premium Water Services | 2 | 3,625 | 50 | 2006 |
| [Associated Environmental Ind Corp](/driller/associated-environmental-ind-corp.md) | 1 | 45 | — | 2024 |
| [Moy's Water Well Drilling & Services of Texas](/driller/moy-s-water-well-drilling-services-of-texas.md) | 1 | 4,050 | 900 | 2019 |
| [Bull's Eye Services, LLC](/driller/bull-s-eye-services-llc.md) | 1 | — | 375 | 2012 |
| Water Well Sevices, Inc. | 1 | 720 | — | 2011 |
| [Cherokee Drilling](/driller/cherokee-drilling.md) | 1 | 4,060 | — | 2010 |
| [Evans Drilling](/driller/evans-drilling.md) | 1 | 3,520 | 450 | 2009 |
| [Edward Pawlik & Son Well Service](/driller/edward-pawlik-son-well-service.md) | 1 | 345 | 60 | 2005 |
| [Hinojosa Services](/driller/hinojosa-services.md) | 1 | — | — | 2005 |

### What the wells are for

*Purpose, and how deep each went.*

| Purpose | Wells | Share | Median depth, ft |
|---|---|---|---|
| Monitor | 115 | 66.5% | 44 |
| Environmental Soil Boring | 32 | 18.5% | 10 |
| Injection | 7 | 4.0% | 818 |
| Rig Supply | 6 | 3.5% | 4,060 |
| Fracking Supply | 5 | 2.9% | 2,780 |
| Domestic | 3 | 1.7% | 431 |
| Stock | 2 | 1.2% | 2,600 |
| Other | 1 | 0.6% | 120 |

*By decade drilled.*

| Decade | Reports | Median depth, ft | Water at, ft |
|---|---|---|---|
| 2000s | 46 | 30 | 54 |
| 2010s | 57 | 67 | 100 |
| 2020s | 70 | 25 | 12 |

### The deepest reports on file

*Deepest reports in state well grid 78-21. Column one is the tracking number.*

| Report | Year | Depth, ft | Water at, ft | Yield, gpm | Purpose |
|---|---|---|---|---|---|
| 260525 | 2011 | 4,155 | 169 | 300 | Rig Supply |
| 261068 | 2011 | 4,152 | 153 | 300 | Rig Supply |
| 228625 | 2010 | 4,060 | 75 | — | Rig Supply |
| 530198 | 2019 | 4,050 | 240 | 900 | Irrigation |
| 422776 | 2016 | 4,050 | 175 | 500 | Fracking Supply |
| 237091 | 2010 | 3,770 | 66 | 200 | Rig Supply |
| 80545 | 2006 | 3,625 | 40 | — | Industrial |
| 204102 | 2009 | 3,520 | 43 | 450 | Rig Supply |
| 320116 | 2013 | 2,780 | — | 700 | Fracking Supply |
| 259547 | 2011 | 2,600 | — | 200 | Stock |

Every figure here comes from a report a licensed driller filed on the day the work ended — sometimes decades ago. It describes what was found then, not what a well yields today, and it is not a statement that any well is sound, potable or still in use.

### Drilling a well near grid 78-21?

Depth is only half the quote. What it costs depends on the rock, the casing and the pump. Tell us where and we pass the request to licensed Texas drillers.

We are nobody's agent and have no arrangement with any firm today. [What we do with this](/privacy.md).

This grid falls in [Atascosa County](/county/atascosa.md), [McMullen County](/county/mcmullen.md).

### Grids with a comparable number of reports

- [57-20](/area/57-20.md)
- [80-36](/area/80-36.md)
- [02-59](/area/02-59.md)
- [05-40](/area/05-40.md)
- [34-44](/area/34-44.md)
- [35-43](/area/35-43.md)
- [37-30](/area/37-30.md)
- [10-49](/area/10-49.md)
- [16-55](/area/16-55.md)
- [24-35](/area/24-35.md)
- [44-41](/area/44-41.md)
- [52-44](/area/52-44.md)
- [87-39](/area/87-39.md)

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Página: https://texas-water-wells.pages.dev/area/78-21/
Fonte: Texas Submitted Driller's Report Database — Texas Water Development Board, from reports filed with the Texas Department of Licensing and Regulation
Recolha: 2026-08-23