If you live in Andover and have ever watched rainwater pool against your patio doors or seen your lawn turn into a temporary lake, you’ve probably been told: “You need a soakaway.”

But building a soakaway in Andover isn’t as simple as digging a hole and filling it with rubble. The town’s unique geology—dominated by —makes for a fascinating yet challenging environment for drainage. The Andover Subsoil Paradox The British Geological Survey maps show that most of Andover sits on Cretaceous White Chalk —a soft, white, porous limestone. In theory, chalk is excellent for drainage. Water percolates through it rapidly, meaning a soakaway should work perfectly.

Andover, Hampshire is a town caught between two watery realities. On one hand, it sits in the picturesque Test Valley, known for its crystal-clear chalk streams. On the other, its residents are no strangers to surface water flooding, especially after the wet winters that increasingly batter the South of England.