Sewage treatment plants in Mallorca
Septic tank, treatment plant or holding tank, the documents and maintenance, in detail.
See the guide →Treatment plants · Montuïri
Sewage treatment plants in Montuïri: for the fincas the mains sewer does not reach
The village of Montuïri has its sewer network and its treatment works, shared with Algaida. The fincas on the plain do not: there each house treats its own water, and the Balearic Water Plan sets out how. 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 engineer to submit.
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
- Treated water for irrigation
- Since 1998
GRAF · Image: GRAF
Your village
The water under Montuïri
The Balearic Water Plan devotes an entry to the Montuïri groundwater body (1815M2): 83 km² shared by Montuïri, Algaida, Porreres and Sant Joan. What it says explains why treated water is worth making use of here.
A naturally salty aquifer
According to Annex 9 of the Plan, the Montuïri body is in poor status because of chlorides, with 330 mg/l on average, and has 220 mg/l of sulphates. It is not pollution: the Plan puts it down to natural causes, to the Miocene marls it rests on, and so does not expect it ever to reach good status.
Irrigate with what you treat
With well water like that, the household water, properly treated, is a resource for the garden. The Plan's general rule is exactly that: reuse it on your plot, with 25 m² of green area per population equivalent (art. 70.12).
Small aquifers, changing ground
The Plan describes the body as a set of small aquifers of Jurassic carbonate and Tertiary detrital materials. For the works: from one plot to the next you may hit rock or soil. The excavation is done by your builder, and beforehand we give them in writing how the pit must be prepared according to the manufacturer.
The rules here
Which documents are prepared in Montuïri, and who submits them
A house with no access to the mains sewer needs an on-site treatment system, a sealed holding tank that is emptied periodically or a natural system with a favourable report (art. 70.1 of the Water Plan). The treatment plant is declared to the Direcció General de Recursos Hídrics (DGRH) with proof of purchase and installation, technical specifications, performance and the maintenance plan (art. 70.4).
We prepare and sign those documents as the installation company, and your architect or engineer submits them. If it is a new house on residential urban land without sewers, the prior notification to Recursos Hídrics goes first (Balearic Planning Act 12/2017, fourth transitional provision) and from then there are at most two years for the declaration (art. 70.5).
What we do
What we do in Montuïri, and what others do
- The new treatment plant for your finca on the plain, approved with CE marking and compliant with EN 12566 (art. 70.14), with the treated water meant for irrigation: in Montuïri the well water carries chlorides of natural origin. We work with all brands; for example, the GRAF one2clean.
- The excavation is done by your builder: between marls, limestone and soil, every plot in Montuïri turns out differently, and we give them in writing how the pit must be according to the manufacturer. The sludge is emptied by an authorised waste company (art. 70.7.f).
- Installation, the electrical line and commissioning, as a licensed low-voltage installation company, right up to the outlet connected to the irrigation of your green area. We don't subcontract anyone.
- The documents for the responsible declaration to Recursos Hídrics (art. 70.4), prepared and signed as the installation company; your architect or engineer submits them. If the water were to go to a trench or a soakaway, prior authorisation is also needed.
- 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, so that the unit keeps delivering the performance of art. 70.10.
Sources: Balearic Water Plan, Royal Decree 49/2023 (regulations, art. 70, 71, 76 and 77) · Annex 9 of the Plan, entries for the groundwater body “Montuïri (1815M2)” · EN 12566 · manufacturer's manual (GRAF one2clean, as an example).
How we work
How we do it in Montuïri, in 3 steps
1
Where the finca is and where the water goes
Send us the location, the bed spaces and whether the treated water will go to irrigation, a trench or a soakaway. In Montuïri the first thing is whether the house is in the village, with sewers, or out on the plain.
2
A quote that includes the green area
We send you in writing the unit, installation, electrics and documents, with the green area art. 70.12 asks for: 25 m² per population equivalent. And your builder gets how to prepare the pit.
3
Installation, irrigation and documents
Once the pit is dug, we install, connect the outlet to the irrigation and commission the plant. We hand over the signed documents so your engineer can file the declaration.
Common questions
Frequently asked questions about treatment plants in Montuïri
Is a treatment plant needed on a finca in Montuïri?
Yes, in any house that cannot connect to the mains sewer. The Balearic Water Plan (Royal Decree 49/2023, art. 70.1) accepts three solutions: an on-site treatment system, a sealed holding tank that is emptied periodically or a natural system with a favourable report. The village of Montuïri has a sewer network and a treatment works; the fincas on rural land around it generally do not.
Can I irrigate with the water from the treatment plant?
That is what the rules ask for: reusing the treated water on the plot itself, with 25 m² of green area per population equivalent (art. 70.12 of the Balearic Water Plan, Royal Decree 49/2023). In Montuïri it also makes practical sense: Annex 9 of the Plan gives the aquifer 330 mg/l of chlorides of natural origin, so the well water is brackish for many plants.
My cesspit has been there for ever: why do I have to replace it?
Because a cesspit neither treats the water nor is sealed, and it is not one of the three solutions in art. 70.1 of the Balearic Water Plan (Royal Decree 49/2023). What we install is a new, approved, CE-marked treatment plant compliant with EN 12566 (art. 70.14), with the minimum performance of art. 70.10: BOD₅ 70 %, COD 75 % and suspended solids 70 %.
What will I find when digging in Montuïri?
It depends on the plot. The Balearic Water Plan (Royal Decree 49/2023) describes the subsoil of Montuïri as a set of small aquifers of Jurassic carbonate and Tertiary detrital materials, with marls. You may hit rock or soil. The excavation, the sand bed and the backfill are done by your builder; beforehand we give them in writing how the pit must be prepared according to the manufacturer.
Who submits the documents for the treatment plant?
Your architect or your engineer. As the installation company we prepare and sign what they ask for: the declaration that the installation complies with the rules, the manufacturer's data sheets and performance, the maintenance plan and the electrical installation certificate. With that, the responsible declaration is submitted to the Direcció General de Recursos Hídrics (DGRH) (art. 70.4 of the Balearic Water Plan, Royal Decree 49/2023).
Keep learning
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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 Montuïri with no mains sewer?
Send us the location, the bed spaces of the house, where the water will go and a few photos. We reply within 24-48 hours on working days.