Why “too cheap to drill another 20 m” is a myth

Bore staining isn’t about depth — it’s about chemistry and geology.

In the Perth Basin:

• Iron-rich sands and clays occur in layers, not neatly “below” a certain depth

• Drilling another 20 m often puts you into a different iron-bearing formation, not cleaner water

• Many deep bores stain worse, not better

There is no universal “clean layer” you reach by drilling deeper.

What actually causes brown staining

• Dissolved iron and iron bacteria in the aquifer

• Oxygen exposure once the water is pumped

• Incorrect screen placement across iron-rich zones• Lack of iron management (filtration, chemistry, or dosing)

Depth alone does nothing to address these.

The practical reality

• A deeper bore costs more to drill and more to pump

• It does not guarantee stain-free water

• Many stained bores in Perth are already very deep

That’s why councils, commercial sites, and high-end homes treat the water instead of chasing depth.