Short answer. Five years. Article 506 of the Civil Code provides that the right to make use of public waters is extinguished by non-user for five years. Continuous non-use of the right for that period causes it to be lost by operation of law, alongside expiry of the governing concession.
What the law says
The right to make use of public waters is extinguished by the lapse of the concession and by non-user for five years.
Civil Code, Article 506 — Loss Of Right To Public Waters. Read the full provision →
The five-year non-use rule
Article 506 of the Civil Code states that the right to make use of public waters is extinguished by the lapse of the concession and by non-user for five years. The article identifies two separate causes of extinguishment: the first is the lapse or expiry of the concession under which the right was granted; the second is non-use for five years. These operate independently. Even if your concession has not expired, stopping use of the public water source for five continuous years will extinguish your right to it. Non-use for the prescribed period is treated as an abandonment of the right.
What counts as non-user
Non-user under Article 506 means the actual failure to exercise the right to use the public water. The five-year period is measured by reference to the last time the right was actually used. If you drew water from the public source, then stopped entirely, the five-year clock begins running from the point of cessation. Merely holding the concession on paper without drawing water counts as non-use. The law does not protect a right that the holder has effectively abandoned through inaction, and five years of that inaction is the statutory threshold for treating the right as extinguished.
Lapse of the concession as a separate ground
Apart from non-use, the article also extinguishes the right when the concession itself lapses. A concession is a grant by the government allowing the use of a public resource, and it is typically granted for a fixed period. When the concession period ends without renewal, the right of use is extinguished by lapse — regardless of how actively the right was exercised before expiry. The two grounds operate independently: a concession that lapses extinguishes the right even if use was continuous up to the last day of the concession period; and non-use for five years extinguishes the right even if the concession period has not yet expired.
Practical implications
If you have a concession to use water from a public source but have not been drawing on it for several years, it is worth checking how long the interruption has lasted. Once five years of non-use are complete, the right is extinguished under Article 506, and resuming use after that point would not automatically revive the extinguished right — the legal basis for use would be gone. If you are approaching or have passed the five-year threshold, the question of what can be done to regularize the use of the public water source is one that depends on the terms of the concession and the applicable administrative framework governing water resources.