Reading Opinion No. 114 of 2026 of the Legislation and Opinion Bureau, on whether the Ministry of Public Works and Housing or any competent government body may construct underground tunnels beneath land owned by private individuals without expropriating it, I stopped at a question that looks simple on its face: how far down does ownership of land extend?

What the Civil Code says, and does not say

The opinion begins from Article 1019(2) of the Civil Code, which extends ownership of land to what lies above it and below it, to the extent that secures the owner the beneficial use of the property. The article does not define what is meant by the useful limit in enjoying it in height and in depth, and sets no controls for it. The opinion takes the view that the legislator did not adopt an absolute extension into the subsoil, and that the limits of ownership are tied to the practical benefit the owner derives.

Silence is not a licence for the administration

The absence of a definition does not allow the administration to determine on its own that the depths through which the tunnels pass fall outside the landowner’s title. On the opinion’s reading, administrative bodies may not rely on that phrase to decide for themselves that those depths lie beyond the owner’s ownership. Fixing that limit requires a legal text at the rank of a statute, or an agreement with the owner. Where there is a dispute, the competent court decides it with the assistance of experts.

What the owner can do

The owner may bring an urgent application to halt the works where they touch the part falling within the scope of their ownership. That route is open where there is no legal text fixing the useful limit and no agreement with the owner, and where the conditions for urgent applications are met. Compensation is a matter for the courts if the owner brings a claim, and the burden of proving the damage rests on them.

What it means in practice

In my assessment, this opinion has a practical bearing on anyone who owns land, invests in it, or contracts over it. The depth of a parcel is an element that may require a legal basis or a written agreement with the owner, rather than a unilateral administrative decision. When companies and investors assess any land, they should be asking what infrastructure projects are planned around it, and should know in advance which routes are open to them: as the opinion sets out, a legal text, an agreement, or expropriation.

If the limits of ownership in depth have not been fixed by any text, do we have enough clarity today to price land and the risks attached to it?

Note: this is general legal information and does not constitute legal advice.