Aia

Can you build a house on rustic land?

The Basque Country allows a new house on rustic land only when a farm needs it. Otherwise it has to go in a village, or restore a building.

Ley 2/2006, art. 28. A town plan can be stricter.

Plan in force: Normas Subsidiarias (an older, simpler plan), from 2009. The region's planning viewer ↗

The national urban information system (SIU) maps the land class for 100% of the municipality.

Only the town hall can confirm it, in writing: ask for a certificado urbanístico.

Is there water?

IGME records 2 wells and boreholes in Aia. Half of the 2 with a depth found water at 125–146 m. 14 springs are recorded.

Ground: 68% practically impermeable; 12% low permeability, local groundwater only; 12% karstic or fissured aquifer, high productivity; 6.1% karstic or fissured aquifer, medium productivity.

Choosing where to drill takes a hydrogeologist.

What to watch for

• 2 fires since 2016 reached the municipality: 4 ha in all, the latest in 2026.
• No mapped flood zone (only studied rivers are mapped).
• 24% of the municipality is Natura 2000: new works need the region's consent.
• 22% of the municipality is a protected natural area, whose plan limits what can be done.
• Radon zone I: new and restored homes need radon protection by law.

Living here

• 4G reaches 99% of homes; fibre 87%. Averages for the municipality.
• Rain: 1,459 mm a year (1971–2000), about 1,244 by 2041–2070.
• Summer highs: 22.3 °C, about 24.5 °C by 2041–2070.
• Frost days: 16 a year, about 7 by 2041–2070.

Around it

Zarautz · Asteasu · Zizurkil · Orio · Usurbil · Getaria · Aizarnazabal · Errezil