Worldwide wastewater treatment observatory · 
Portugal
Aguas SB Observatory · public data to understand water
WWTP Frossos
Portugal · official identifier PT18063056
230,000h-e design capacity (2022) · 16th of 527
European Environment Agency — Waterbase-UWWTD, data call 2023 (versión final pública) · official identifier PT18063056 · reported size 230,000 h-e design capacity · received load 158,500 h-e · reported treatment: PST · data year 2022. 16th of 527 records with reported size in the inventory of Portugal; 1.3 % of the sum of those 527 records in h-e (sum of records, not national capacity); nearest inventoried plant at 3.6 km · 9 within 10 km. Reported data with their source; estimates are not measurements of the plant.
Aguas SB does not manage this wastewater treatment plant.
WHAT THE DATA REPORT
Reported data official data · 2022
| Treatment | primary + secondary + tertiary (more stringent) (as reported to the EEA: PST) · reported levels |
|---|---|
| Nitrogen removal | not reported |
| Phosphorus removal | not reported |
| UV disinfection | yes |
| Status | active |
| Reported coordinates | 41.5666, -8.4458 precision reported by the source: level 2 what it means |
| Source and year | European Environment Agency — Waterbase-UWWTD, data call 2023 (versión final pública) · dataset record |
FUENTES PÚBLICAS
What public sources report
Documented milestones
- 2009-02-19 · The extension and refurbishment of the Frossos wastewater treatment plant received a favourable environmental decision with conditions. Portuguese Environment Agency
Facts taken from public documents, with their date and link; an authorisation, a project or a planned capacity do not prove operation or quantities actually treated. Aguas SB editorial layer, lot L05; it does not change the official data.
REGULATORY REFERENCES
Referencia normativa: Portugal
Regulatory framework of Portugal · Directive (EU) 2024/3019: reported-capacity band 150,000 p.e. or more; obligations are set by agglomeration load, not by the capacity of this plant. Individual applicability is not determined in this profile.
SCENARIO
Reference energy scenario for this load estimate · simulator engine
what this estimate is · Inputs: 158,500 p.e. of reported load; equivalent average load 158,500 p.e. with the reference profile of Portugal (hypothesis with reported load and reference profile; not a measurement). Open this scenario in the simulator · how it is calculated and what it is not.
Reference scenario computed on the server from the reported load and the country profile; an estimate, not a measurement. The simulator recomputes it when opened.
WATER THAT COULD RETURN
Reuse potential
what this estimate is · Volume estimated from the reported load (31,700 m³/day of reference), not measured or available for reclamation.
NEARBY PLANTS
Nearby wastewater treatment plants
| Plant | Distance | Capacity (h-e) | Load 2022 | Treatment |
|---|---|---|---|---|
| Palmeira | 3.6 km | 32,000 | 7,000 | primary, secondary and tertiary |
| Ruaes | 3.6 km | 20,000 | 10,000 | primary, secondary and tertiary |
| Cavado/Homem | 5.1 km | 49,891 | 28,500 | primary, secondary and tertiary |
| Cabreiros | 5.7 km | 6,900 | 6,200 | primary and secondary |
| Celeiros | 6.4 km | 19,200 | 19,200 | primary, secondary and tertiary |
Distances are between reported coordinates; proximity does not establish a hydraulic connection.
QUESTIONS
Frequently asked questions about this plant
What capacity does WWTP Frossos report?
Reported size: 230,000 h-e design capacity. Received load: 158,500 h-e. Units are retained without conversion.
What treatment is reported?
Treatment PST. Nitrogen, phosphorus and UV are shown only when explicitly reported.
How much energy would a reference plant use with the load of Frossos?
Aguas SB simulator reference scenario for 158,500 p.e. of reported load: 4,931,587 kWh per year (31.1 kWh per p.e. of average load), with aeration as 59 % of consumption. Estimate with the country reference profile; not a measurement of the plant.
SOURCE AND CORRECTIONS
Source
reported data · European Environment Agency — Waterbase-UWWTD, data call 2023 (versión final pública) · data 2022 · edition 2023 · source licence: CC BY 4.0 · JSON for this plant · suggest a correction · catalogue 2026-11-06. Reported data, not a current inspection; no compliance judgements.