Updated 2026-10-23
Can I rely on my neighbours' well records to decide where to drill a borehole?
Neighbours' well records are a useful starting point in sand and gravel, but in granite, basalt, dolomite and deep clay they can mislead, because water follows narrow fractures. In Bavaria, WaterLocation found 200 m³ a day at 22 m 47 m from one of four dry boreholes up to 118 m deep; in Catalonia, where a driller with 40 years' experience said there was no water, the state test confirmed 648 m³ a day.
What neighbours' records can tell you
- Rough depth range of the first water strikes and the static water level in the area.
- What you will drill through: soil, clay thickness, the rock below. This helps a driller plan casing and equipment.
- Water quality hints, such as salty water in a nearby hole.
In uniform sand and gravel aquifers, a neighbour's good well is a fair sign that a hole next door will also find water at a similar depth.
Why they mislead in hard rock and under clay
In granite, basalt, dolomite, limestone and under thick clay, groundwater moves through fractures and fault zones that may be only a few metres wide. A productive well next door may sit right on a fracture that does not cross your land; a dry hole next door may have missed a fracture that does. Records show what was found at that point, not between the points.
Cases where nearby data pointed the wrong way
| Site | What the earlier data said | What the survey found | Yield |
|---|---|---|---|
| Mitterfirmiansreut, Germany (granite hilltop) | Four empty boreholes up to 118 m; other drillers gave negative forecasts | Water at 22 m, 47 m from one of the empty holes | 200 m³/day |
| Catalonia, Spain (100+ m of clay and loam) | Several failed boreholes; a driller with 40 years' experience said no water | Water at 136 m, static level 39 m, state pumping test | 648 m³/day |
| Two farms, South Africa (dolomite) | Five dry boreholes and one very salty; geologists expected only salty water | Fresh water at 14 m and 97 m | 86 + 260 m³/day |
| Kalahari, South Africa (rock and quartz) | 25 boreholes on the site, only four with a steady flow | 150 m borehole, static level 28 m | ≈200 m³/day |
Figures from WaterLocation project reports.
How to use the records well
- Collect what exists: depths, drilling logs, water strikes, static levels, yields and quality of nearby and earlier holes on your own site.
- Treat them as background, not as a drilling point. Note where they disagree with each other; in fractured rock that is normal.
- Survey your own land for water-bearing fractures and get a drilling point, depth and forecast yield.
- Drill to that specification and confirm the yield with a pumping test.
WaterLocation uses existing logs in the analysis, so send them with your request. Surveys are quoted per site. See also borehole siting methods compared and what to do after a dry borehole.
Sources
Questions
My neighbour hit water at 40 m. Should I drill to 40 m too?
In sand and gravel that is a reasonable first guess. In fractured rock or under deep clay the depth can differ a lot over short distances: on WaterLocation sites water came in at 22 m next to holes of up to 118 m, and at 136 m below clay where earlier holes failed.
Several dry holes nearby: does that mean there is no water?
Not necessarily. On the Bavarian, Catalan and South African sites above, dry or failed holes came first and productive wells were found later on the same land.
Are government borehole databases useful?
Yes, as background on geology and typical depths. They have the same limit as neighbours' records: they describe the points that were drilled, not the fractures between them.