Worldwide wastewater treatment observatory · 
Netherlands
Aguas SB Observatory · public data to understand water
WWTP UWWTP KATWIJK
Netherlands · official identifier NL13041
144,000h-e design capacity (2022) · 39th of 315 (tied with 2 others)
European Environment Agency — Waterbase-UWWTD, data call 2023 (versión final pública) · official identifier NL13041 · reported size 144,000 h-e design capacity · received load 132,616 h-e · reported treatment: PST · data year 2022. 39th of 315 records with reported size in the inventory of Netherlands (tied with 2 others); 0.68 % of the sum of those 315 records in h-e (sum of records, not national capacity); nearest inventoried plant at 2.1 km · 4 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 | yes |
| Phosphorus removal | yes |
| UV disinfection | not reported |
| Status | active |
| Reported coordinates | 52.2025, 4.4402 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
- 1975 · The Dutch inventory records 1975 as the construction year of the AWZI Katwijk treatment plant. Dutch water authorities, PDOK inventory
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 L07; it does not change the official data.
REGULATORY REFERENCES
Referencia normativa: Netherlands
Regulatory framework of Netherlands · Directive (EU) 2024/3019: reported-capacity band 10,000 to 149,999 p.e.; 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: 132,616 p.e. of reported load; equivalent average load 132,458 p.e. with the reference profile of Netherlands (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 (35,011 m³/day of reference), not measured or available for reclamation.
NEARBY PLANTS
Nearby wastewater treatment plants
| Plant | Distance | Capacity (h-e) | Load 2022 | Treatment |
|---|---|---|---|---|
| Uwwtp Noordwijk | 2.1 km | 71,100 | 60,000 | primary, secondary and tertiary |
| Uwwtp Leiden-Noord | 4.8 km | 99,000 | 68,366 | primary, secondary and tertiary |
| Uwwtp Leiden-Zuidwest | 7.7 km | 81,000 | 98,766 | primary, secondary and tertiary |
| Uwwtp Lisse | 9.7 km | 31,500 | 21,650 | primary, secondary and tertiary |
| Uwwtp Nieuwe Wetering | 11.7 km | 22,500 | 19,950 | 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 UWWTP KATWIJK report?
Reported size: 144,000 h-e design capacity. Received load: 132,616 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 UWWTP KATWIJK?
Aguas SB simulator reference scenario for 132,616 p.e. of reported load: 4,715,914 kWh per year (35.6 kWh per p.e. of average load), with aeration as 53 % 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.