Short answer. Yes. Article 631 lists merger of ownership of the dominant and servient estates in the same person as one of the ways an easement is extinguished. Once a single owner holds both properties, the easement between them serves no purpose and is absorbed into the owner's unified control.
What the law says
By merger in the same person of the ownership of the dominant and servient estates
Civil Code, Article 631 — How Easements Are Extinguished. Read the full provision →
What the law says
it shall revive if the subsequent condition of the estates or either of them should again permit its use
Civil Code, Article 631 — How Easements Are Extinguished. Read the full provision →
Merger extinguishes the easement
Article 631 opens its list of how easements end with exactly this scenario: By merger in the same person of the ownership of the dominant and servient estates. An easement, such as a right of way, exists to let the owner of one property, the dominant estate, use part of a neighboring property, the servient estate, that belongs to someone else. When both properties come under one owner, whether by purchase, inheritance, or any other lawful means, there is no longer a neighboring owner to be burdened, so the legal relationship the easement depended on disappears.
Why merger makes the easement pointless
An easement is fundamentally a right exercised over someone else's land. Once the same person owns both parcels, they do not need a legal easement to cross, draw water from, or otherwise use their own land in the way the easement used to permit, because ordinary ownership already gives them full use of the whole property. Keeping a formal easement alive between two parcels owned by the same person would serve no practical function, so the law simply treats the right as absorbed into full, undivided ownership.
What happens if the properties are later separated again
This is not necessarily the final word on the easement if the two properties are later split apart, for example when the owner sells one of them to a different buyer. Whether an equivalent easement arises again generally depends on how the properties are separated and what, if anything, the parties agree to at that point, rather than on the old easement automatically springing back to life. Article 631 elsewhere allows an easement to revive once an obstructing condition is lifted, but merger operates differently, because it ends the easement outright rather than merely suspending its use.
What to check if you are buying either property
Anyone buying either the dominant or servient estate should check whether the two properties are currently under common ownership, and, if they are being separated by the very sale in question, whether a new easement is being created or reserved in the deed. A buyer cannot assume an old, extinguished easement is still enforceable just because it once existed and still appears on an outdated title record, since merger may already have wiped it out before the current transaction.