How to read a Texas well depth

Four things that decide whether you are reading these numbers right.

1. Two depths, and they are not the same

Depth drilled is how far the hole went — the bottom of the driller’s log. Water struck at is where water first appeared. Across Texas the medians are 180 ft and 80 ft: wells routinely go well past the first water, to reach a bed that will keep producing.

2. It is a report, not an inspection

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.

626,104 of 708,722 reports carry a depth, 376,730 a water level and 294,676 a tested yield. A blank is a blank: we do not fill it in.

3. Medians, never averages

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.

Measured on the file we hold: 136 reports show a yield above 3,000 gpm and 103 a depth beyond 5,000 ft. They stay in the file and are marked; they are left out of every median on this site.

4. The rock log is the driller’s own words

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.

Two firms working the same street may write « red clay » and « clay, red ». We do not merge them, because deciding they are the same is a geological judgement we are not in a position to make. Read the column as a set of impressions that agree, not as a stratigraphy.

Start from the counties, or see what is covered.

Drilling a well in Texas?

Depth is only half the quote — the rock, the casing and the pump decide the rest. 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.