Building a house in Costa Rica: why water comes first, not last
When you picture your dream home in Costa Rica, you probably imagine ocean breezes, howler monkeys in the distance and a lush green backdrop. You probably do not imagine queuing at a municipal office because nobody can promise you a single legal drop of drinking water. Yet for anyone building here today, securing a reliable, legal source of potable water is as important as choosing the right plot – and in the drier regions, it can be the deciding factor in whether you can build at all.
Why is water availability such a big issue when building in Costa Rica?
Water availability is a big issue because you cannot get a building permit without proving you have a legal, recognised source of potable water.
Costa Rica does have plenty of rainfall, but it doesn’t automatically translate into approved, pressurised water at your future kitchen tap. In places such as Guanacaste and the Central Pacific, growth has outpaced infrastructure and climate change has made dry seasons longer and harsher. That combination means:
- Some communities have moratoriums on new water connections
- Existing systems (AyA or ASADA) may be at full capacity
- New private wells may be restricted or completely banned
- Municipalities are far stricter about documentation than they were a decade ago
So when you are evaluating land for a future home, water should sit right alongside:
- Location and access
- Building platform and views
- Soil stability and drainage
- Zoning and land-use restrictions
If the water situation is uncertain, treat it as a red flag, no matter how attractive the property looks.
Who actually controls potable water in Costa Rica?
Potable water in Costa Rica is controlled by the state, which holds ownership and regulatory power over water resources.
The key public body is AyA (Acueductos y Alcantarillados), the national authority responsible for:
- Planning and regulating public water systems
- Granting approvals and supervising local providers
- Setting technical standards and quality requirements
Even when you are dealing with a small local association or a private well, the legal framework still flows from the state’s control of water. This is why “having a spring nearby” or “the neighbour says there’s plenty of water” is not enough. You need a source that is recognised within this regulatory structure.
What are AyA, ASADAS and SENARA – and why do they matter?
AyA, ASADAS and SENARA matter because they are the bodies that confirm whether your water source is legal, recognised and sufficient for a building permit.
Here’s how they fit together:
- AyA (Acueductos y Alcantarillados)
- National authority for water and sewerage
- Issues regulations and supervises systems across the country
- In some areas, AyA itself is your direct water provider
- ASADAS (Asociaciones Administradoras de los Sistemas de Acueductos y Alcantarillados Comunales)
- Community-based water associations, common in semi-rural and rural areas
- Operate local aqueducts and distribute water to homes and businesses
- Function under AyA’s umbrella and must respect its regulations
- SENARA (Servicio Nacional de Aguas Subterráneas, Riego y Avenamiento)
- Manages the national registry and technical control of groundwater and wells
- Registers well concessions and oversees their technical parameters
If your future home depends on a public system, you will be dealing with AyA or an ASADA. If it depends on a private well, you will see SENARA and MINAE (the Environment Ministry) in the paperwork. In all cases, if the source is not documented and approved within one of these frameworks, you effectively have no legal water as far as the municipality is concerned.
Can I just drill my own well on my property?
You cannot simply drill your own well; you need a government concession, and in many dry areas new wells are restricted or outright banned.
In theory, a private well can be an excellent, long-term water solution. In practice, it is tightly regulated:
- You must obtain a concession granted by the government
- The well must be registered with SENARA
- MINAE must authorise the use of the groundwater
- Technical studies and environmental assessments are often required
In parts of Guanacaste and other water-stressed regions, authorities have frozen or severely limited new drilling because aquifers are under pressure. If someone is selling you a “perfect building lot with the possibility to drill a well”, you need to verify today’s rules very carefully before relying on that promise.
What water documentation do I need for a municipal building permit?
To obtain a municipal building permit, you must present a formal letter confirming an approved potable water source, alongside your architectural plans.
For most private builds, this means one of the following:
- A letter from AyA or the relevant ASADA confirming that:
- Your specific plot is within their service area
- They have capacity to provide you with a connection
- They authorise water service for your project
- Or, documentation of a registered well concession, including:
- Proof of the concession granted by the relevant authority
- Registration with SENARA
- Evidence that the well provides sufficient potable water for the planned construction
This letter or concession proof is submitted together with:
- Architect-stamped building plans
- Land ownership documents
- Any other technical studies the municipality requires
Without the water letter or well documentation, your building permit application will simply not move forward.
When should water checks happen in the buying process?
Water checks should happen before you buy, as part of your legal and technical due diligence.
Do not wait until you are ready to build to ask about water. A sensible buyer will:
- Make the promise of a valid water letter a written condition of the purchase contract
- Ask the seller to provide the current letter from AyA or the ASADA, or the well concession documents
- Use a Costa Rican lawyer to verify the authenticity and validity of those documents
- Confirm with the municipality that the type of letter provided is acceptable for a building permit
If the seller cannot provide clear, recent documentation, you have three options:
- Renegotiate (with strong protections written into the contract)
- Put the property on hold until water is clarified
- Walk away and focus on land with a clean water file
In today’s market, a plot that comes with transparent, up-to-date water documentation is worth more than one that relies on vague promises.
FAQs about water and building permits in Costa Rica
Do I really need a lawyer to check the water situation?
Yes, you really should use a local lawyer, ideally one experienced in property and water issues, to review letters, concessions and municipal requirements.
Is a water letter valid forever?
Not necessarily. Some letters have a specific validity period or may be subject to system capacity. Always check date, conditions and whether the municipality still accepts the format.
What if there is an existing house already built on the land?
If a house already has a legal connection, that is a good sign – but you still need to confirm that adding another house, guest casita or apartments will be allowed under current capacity and regulations.
Can a spring or river on the land be used as my water source?
Not automatically. Even if water is physically present, using it as potable water usually requires permits, treatment and formal approvals. Never assume it will qualify without checking.
Is the situation the same everywhere in Costa Rica?
No. Some central valley areas have robust networks, while coastal and drier regions may be under stress. Always treat each property and municipality as a separate case.
