Water wells in Collin County, Texas
4,321 well reports on file. The median well here was taken to 20 ft and struck water at 441 ft — against 180 ft and 80 ft across Texas.
What you will drill through in Collin County
| Depth, ft | What was logged there |
|---|---|
| 0–25 ft | Concrete 440, Brown Clay 270, Tan Clay 243, Topsoil 241, Gray Shale 222, Tan Limestone 214 |
| 25–50 ft | Gray Shale 94, Austin Chalk 37, Shale 16, Gray Limestone 16, Limestone 11, Tan Clay 11 |
| 50–100 ft | Gray Shale 107, Grey Shale 6, Shale 5, Austin Chalk 5, Gray Clay 4, Blue Shale 4 |
| 100–200 ft | Gray Shale 65, Shale 7, Black Clay 2, Gray Clay 2, Blue Clay 2, Clay 2 |
| 200–300 ft | Gray Shale 60, Sand 32, Shale 10, Black Soil 5, Sandy Shale 4, Rock 4 |
| 300–500 ft | Sand 83, Gray Shale 60, Shale 20, Sandy Shale 16, Gray Shale/Sand 8, Sand Shale Sequence 7 |
| 500–1000 ft | Sand 332, Gray Shale 199, Shale 144, Sand And Shale 28, Sandy Gray Shale 28, Broken Sand 32 |
| 1000–5000 ft | Sand 117, Shale 74, Gray Shale 53, Sandy Shale 26, Limestone 15, Broken Sand 12 |
The rock column here is what drillers wrote down, layer by layer, in their own words — 5,345,462 layers across 707,856 wells. It is not a geological survey: two drillers may call the same clay by two names, and this site does not correct them.
Who drills in Collin County
What the wells are for
| Purpose | Wells | Share | Median depth, ft |
|---|---|---|---|
| Monitor | 1,839 | 42.6% | 20 |
| Environmental Soil Boring | 1,482 | 34.3% | 10 |
| Irrigation | 437 | 10.1% | 880 |
| Closed-Loop Geothermal | 149 | 3.4% | 250 |
| Domestic | 125 | 2.9% | 900 |
| Stock | 101 | 2.3% | 1,000 |
| Test Well | 65 | 1.5% | 20 |
| Other | 59 | 1.4% | 20 |
| Decade | Reports | Median depth, ft | Water at, ft |
|---|---|---|---|
| 2000s | 1,420 | 20 | 450 |
| 2010s | 1,928 | 19 | 278 |
| 2020s | 973 | 20 | 430 |
The deepest reports on file
| Report | Year | Depth, ft | Water at, ft | Yield, gpm | Purpose |
|---|---|---|---|---|---|
| 712814 | 2025 | 3,560 | — | — | Public Supply |
| 25128 | 2003 | 3,200 | 505 | 1,160 | Irrigation |
| 252730 | 2008 | 3,105 | 600 | 403 | Public Supply |
| 685435 | 2024 | 2,850 | 600 | — | Public Supply |
| 202016 | 2003 | 2,730 | 568 | 300 | Irrigation |
| 638186 | 2023 | 2,530 | 846 | — | Public Supply |
| 95109 | 2006 | 2,490 | — | — | Public Supply |
| 554842 | 2020 | 2,450 | 789 | 380 | Public Supply |
| 715624 | 2025 | 2,400 | 850 | 180 | Irrigation |
| 349893 | 2013 | 2,350 | 881 | 430 | Public Supply |
Every figure on this site is a median, never an average. On reported yield the average is twice the median, because a handful of entries are typing errors — the largest reads 2,200,100 gallons per minute against 30,078 for the next one. Yields above 3,000 gpm (136 wells, 0.045%) and depths beyond 5,000 ft (103 wells, 0.016%) are kept in the file, marked, and left out of the medians.
Drilling a well in Collin County?
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.
Counties with a comparable number of reports
A sliding window, not a ranking. Every county.