The short answer
You cannot get a building permit in Costa Rica without a water availability letter for that specific lot. It comes from the national water utility (AyA), a registered local water association (ASADA), a municipality that runs its own system, or a legal well concession. Check it before you buy: a growing share of requests are denied.
Why water decides everything
Without a valid availability letter the municipality will not issue a construction permit, the building plans cannot be registered, and you may not be able to get an electricity meter. A lot can have a clean title and still be impossible to build on.
Who can issue the letter
Legal water can come from four places:
- AyA, where it operates the local aqueduct
- An ASADA, a community water association registered with AyA
- A municipality that runs its own water system
- A concession for a legally permitted well or spring on the property
Availability is not the same as capacity
Ask for a water availability letter. A capacity letter only says the system exists, does not confirm water for your lot, and is not accepted for a building permit.
A positive letter usually lasts about twelve months, after which the provider can ask for a new inspection. A letter the seller obtained years ago proves little.
Why requests get denied
Many rural systems are at their limit. Reporting in 2026 put denials at roughly one request in four, and in parts of the Nicoya Peninsula AyA stopped a group of ASADAs from issuing letters for new construction altogether. It varies district by district, so ask about the specific lot.
The other permits
With water confirmed, building a house also needs:
- A land-use certificate (uso de suelo) from the municipality, confirming a house is allowed there
- Plans prepared by a licensed architect or engineer and registered with their professional college
- The municipal construction permit
- An environmental review for larger projects
Rivers and springs limit where you can build
The Forestry Law sets protection areas around water where building is not allowed: around permanent springs and along rivers and creeks, with the width depending on the terrain. A river on a lot is a selling point, but measure how much of the land it puts off limits.
Questions buyers ask
Not legally. Using it for a house needs a concession, and the area around a permanent spring is protected from building.