Atenas and Grecia sit on the western side of Costa Rica's Central Valley, in the province of Alajuela, about an hour from San José and from the airport. Mild weather, views over the valleys and the chance to own some land have made both towns popular with retirees and families from abroad. Many of the homes they buy or build are on former coffee farms and pastures, on hillsides, outside the town centers.
This is our home region. Ingeniería de las Aguas is based in Palmares, also in western Alajuela, so Atenas and Grecia are close by.
Hillside lots on old farmland
A typical project here is a single-family home, sometimes with a guest house or a casita for staff, on a lot carved out of a larger farm. Most of these properties have no sewer, so the wastewater goes to a septic tank and a drain field on the lot.
What we look at first:
- Slope. Decree 42075-S-MINAE does not allow drain field trenches on ground steeper than 30 %, and asks for a 2-meter setback from the top of slopes steeper than 25 %. On a hillside with a view, the flat area you want for the house is often the same one you need for the drain field.
- Soil. Volcanic soils in the Central Valley vary a lot, from soils that absorb well to heavy clays that barely drain. The regulation accepts trenches only between 2 and 24 minutes per centimeter, measured after a 24-hour soak.
- Streams and springs. Coffee country is full of small streams and springs. Their protection areas under the Water Law and the Forestry Law limit where a drain field can go.
- Everyone who uses it. The house, the guest house, the staff quarters and the pool shower all count. Our guide on septic system sizing explains how flow is calculated.
For most homes, an improved septic tank with a well-designed drain field is the right answer. It is designed and presented with the construction plans, as our guide on wastewater permits for building a house explains.
Water: ASADAs, municipal systems and springs
The water side is just as important here. Depending on the district, drinking water may come from a municipal system, from AyA (the national water utility) or from an ASADA, a community water association that runs the local aqueduct under an agreement with AyA. Whoever serves the lot issues the water availability letter that you need for a construction permit, and in some rural areas that letter can be hard to get.
Before buying, ask for that letter or at least confirm with the operator that service is possible. Our guide on buying land: water and wastewater checks covers it in detail.
Many farms also have a spring or an old well. In Costa Rica, water is public property: the Water Law allows wells for domestic use within your property, but most other uses need a concession from MINAE's Water Directorate. Read water wells and concessions before you count on that water, and see our water systems page for storage, treatment and water quality analysis.
Small developments and gated communities
Atenas and Grecia also have small gated communities and lot subdivisions. Once a development's combined water use goes above 190 cubic meters per month, individual septic tanks are no longer the answer for shared wastewater: the project needs a treatment plant approved under Decree 39887-S-MINAE, an internal sewer network and, often, a pumping station. The condominium will then file operational reports with the Ministry of Health.
Dry season, wet season
The western Central Valley follows the Pacific pattern described by the National Meteorological Institute: a dry season from December to March, April as a transition, and rains from May to October, with a short drier spell in July and August and the heaviest rain in September and October. A drain field sized correctly handles the wet months. One sized "by eye", or tested in March without the 24-hour soak, tends to show its limits in October.
How we help in Atenas and Grecia
Being nearby, we can visit, inspect and supervise more easily. We:
- design and build improved septic systems and drain fields from the percolation test results;
- design and build treatment plants, sewers, pumping stations and drainage for small developments;
- review and rehabilitate systems that smell, overflow or no longer fit the property;
- run water quality analyses and design drinking water treatment and storage;
- handle permits with the Ministry of Health, AyA and the municipalities, and supervise construction.
If you are also considering the west side of San José, see Escazú and Santa Ana.
Send us the location, a few photos and what you plan to build on WhatsApp, or write through our contact page.