Sewage treatment plants in Mallorca
Septic tank, treatment plant or holding tank, the documents and maintenance, in detail.
See the guide →Treatment plants · Bunyola
Sewage treatment plants in Bunyola, for the fincas in the mountains
Bunyola's waste water runs down a pipe to the treatment works in Palma. The fincas in the mountains, towards Orient and along the valleys of the municipality, are a long way from that pipe: each house treats its own, and underneath lies an aquifer that Palma drinks from. We are Joaquín and Juan, installers in Mallorca since 1998: we supply the new treatment plant, install it, do the electrics and prepare and sign the documents for your architect or engineer to file.
Send us photos and details · Reply within 24-48 hours on working days · We assist you in English, Spanish and German
- New approved unit
- Signed documents
- Mountain fincas
- Since 1998
Image: GRAF
Your area
Bunyola: mains in the settlements, a treatment plant in the mountains
Bunyola has 7,678 inhabitants, and 1,742 of them live scattered outside the settlements, according to the INE's 2025 Nomenclátor (gazetteer). For those houses, what counts is article 70 of the Balearic Water Plan.
The pipe to Palma
EMAYA explains that its EDAR 2 treatment works receives waste water from Bunyola, as well as from Esporles and Marratxí, and the Water Plan includes a measure of €1.2 million to upgrade the sewer pipe coming from Bunyola. That is the network of the settlements. A finca with no access to it needs its own system.
S'Estremera: water for Palma
Under the municipality lies the Bunyola groundwater body (1808M1), where EMAYA has the s'Estremera wells that supply Palma. Where there are supply wells there are protection perimeters, and inside the maximum-restriction one the treatment plant has to include disinfection and denitrification (art. 70.10, table 13).
Rock, slope and little soil
In the Serra de Tramuntana the pit is almost always dug in rock and level ground is scarce. A place has to be found for the unit, for the green irrigation area (25 m² per population equivalent, art. 70.12) and for the lorry that empties the sludge to get in.
Sources: Balearic Water Plan, Royal Decree 49/2023 (regulations, art. 70 and 71) · Annex 9 of the Plan, measures for Palma's sewerage (pipe coming from Bunyola) and general measures for rural land · EN 12566 · manufacturer's manual (GRAF one2clean, as an example).
The rules here
What the rules ask of a mountain finca
An approved unit, with CE marking and compliant with EN 12566 (art. 70.14), that does not take in rainwater (art. 70.7.d) and is installed without contaminating the groundwater, taking the terrain into account (art. 70.7.a and c). The Plan itself provides for Mallorca a measure to upgrade, replace or install septic tanks on rural land.
The responsible declaration to the Balearic water authority (Direcció General de Recursos Hídrics) is always filed (art. 70.4). If there is no land to irrigate and the water goes to a drainage trench, a favourable report and a prior authorisation are needed (art. 70.12). As the installation company we prepare and sign the documents; your architect or engineer files them.
What we do
What we do in Bunyola, and what others do
- Replacing the cesspit with a new treatment plant, approved with CE marking and compliant with EN 12566 (art. 70.14), with disinfection and denitrification if the estate falls inside the maximum-restriction perimeter of a supply well. We work with all brands; as an example, the GRAF one2clean.
- Installation, electrics and commissioning on mountain estates in Bunyola and Orient, with gutters and patios kept separate, because rainwater must not enter the unit (art. 70.7.d). As a licensed low-voltage installation company. We don't subcontract anyone.
- A pit in rock and on a slope: your builder digs it to the pit and backfill dimensions we give in writing according to the manufacturer, in a spot the authorised waste company's truck can reach to empty the sludge (art. 70.7.f).
- The unit's documents, for Recursos Hídrics and for your engineer, who also handles the works permit at the Town Hall and, where relevant, the Natural Area. We prepare and sign them as the installation company; your architect or engineer files them.
- The services required by the rules or, if the manufacturer asks for more, the manufacturer's (on the GRAF one2clean, twice a year), with a signed report. Beneath Bunyola is the s'Estremera water that Palma drinks.
How we work
How we do it in Bunyola, in 3 steps
1
What your land is like
Location, bed spaces, slope, rock and photos. We check whether the estate is close to the s'Estremera wells and whether there is room for 25 m² of green area per population equivalent.
2
A quote built for the mountains
Unit, installation, electrics and documents, in writing; and for your builder, how to open the pit in rock. With no green area, a holding tank or a drainage trench with prior authorisation.
3
Installation and documents for your engineer
We install below the house, so the water flows down by gravity, commission the plant and hand over the signed documents for your engineer to file.
Keep learning
More on treatment plants and energy in Bunyola
The general guide to treatment plants and what else we do in your area.
Solar panels in Bunyola
Self-consumption for the house, the treatment plant blower included.
See solar in Bunyola →Heat pumps in Bunyola
Heating and hot water with a heat pump.
See heat pumps in Bunyola →Across Mallorca
Sewage treatment plants in the Raiguer and the Tramuntana: Alaró · Consell · Sencelles · Selva · Esporles, or see the guide to sewage treatment plants in Mallorca →
And for the summer: air conditioning in Bunyola →
Need the house drainage (downpipes, rainwater, chambers)? Drainage in Mallorca →
Sewage treatment plants near Bunyola: Palma · Marratxí · Santa Maria del Camí · Sóller
See our work and customer reviews on the JSL Google Maps profile →
Common questions
Frequently asked questions about treatment plants in Bunyola
Where does Bunyola's waste water go?
To Palma. EMAYA states that its EDAR 2 treatment works receives waste water from Bunyola, Esporles and Marratxí, and the Balearic Water Plan (Royal Decree 49/2023, Annex 9) sets aside €1.2 million to upgrade the sewer pipe coming from Bunyola. A mountain finca or a country house with no access to that network needs its own system (art. 70.1).
I have a finca in Orient with an old cesspit: what needs to be done?
Replace it. A cesspit neither treats the water nor is it sealed, and the Balearic Water Plan (Royal Decree 49/2023, art. 70.1) only accepts an on-site treatment system, a sealed holding tank emptied periodically or a natural system with a favourable report. We install a new treatment plant, approved under EN 12566, and hand you the signed documents.
Why do you ask me about the s'Estremera wells?
Because water for Palma comes from there. EMAYA's s'Estremera wells are in the Bunyola groundwater body (1808M1). If your plot falls inside the maximum-restriction perimeter of a supply well, the Water Plan requires disinfection and denitrification (art. 70.10, table 13 of Royal Decree 49/2023). We look it up on the DGRH map viewer with your location.
My land is rock and on a slope: can the treatment plant be installed?
Yes. The excavation is done by your builder, with the dimensions of the pit and the backfill that we give them in writing according to the manufacturer's manual. The treatment plant goes below the house, so that the water reaches it by gravity. If there aren't 25 m² of green area per population equivalent (art. 70.12), what remains is the sealed holding tank emptied periodically or the drainage trench with a prior authorisation. It is what we come across on the fincas of Bunyola and Orient.
Can rainwater go to the treatment plant?
No. The Balearic Water Plan prohibits the system from taking in rainwater (art. 70.7.d of Royal Decree 49/2023): a downpour would wash out the unit's biology. On a finca in Bunyola, the gutters and courtyards are drained separately, to a cistern or onto the land.
Do I need a permit because I'm in the Serra de Tramuntana?
The treatment plant is declared to the Direcció General de Recursos Hídrics (art. 70.4 of the Balearic Water Plan, Royal Decree 49/2023). The building work is also processed at Bunyola town hall; if the finca is in the Serra de Tramuntana Natural Area (Paraje Natural), its Natural Resources Management Plan (Decree 19/2007) is taken into account, and Orient has been a historic site since 2010. Your architect or engineer handles that; we give them the unit's documentation.
Quality
We work with all brands
As an example, GRAF tanks. We propose the unit for each house and what the area requires.
A finca in Bunyola or Orient with no mains sewer?
Send us the location, the number of bed spaces, what the land is like and a few photos. We reply within 24-48 hours on working days.