Europe: for the people who run the plant

What the public record says about your plant, and where it is likely wrong.

What is driving spend

Under the recast Urban Waste Water Treatment Directive (EU 2024/3019), tertiary treatment for nitrogen and phosphorus applies from 10,000 population equivalent upward, with phased deadlines through 2039 and stricter limits for medium plants by 2045. Separately, the directive lowers the secondary treatment threshold to 1,000 p.e. by 2035, a real obligation for smaller communities, but not a nutrient one.

Reading EEA's WISE UWWTD register for the warm member states, 4,704 plants have secondary treatment and no nitrogen and/or phosphorus removal. 1,371 of them are at or above the 10,000 p.e. tertiary threshold. The remaining 3,333 sit below it and face a secondary-treatment obligation instead. Energy neutrality also applies from 10,000 p.e., as a national-level target by 2045 rather than a per-plant one.

You already know your plant better than any national dataset does. The value of a dataset like this is the opposite direction: it tells you how your plant looks from outside, to a regulator, a funder or a vendor who has never visited.

What the directive changes for a plant your size

The threshold that matters is 10,000 population equivalent. At or above it, the recast UWWTD brings you into tertiary treatment for nitrogen and phosphorus, on a phased timetable running to 2039, with tighter limits for medium plants by 2045. 1,371 plants across the warm member states are above that line today with no nutrient removal in place.

Below 10,000 p.e. the obligation is different, and it is worth being precise about it. The directive lowers the secondary treatment threshold to 1,000 p.e. by 2035. That is a capital obligation, but it is not nutrient removal, and anyone telling a 2,000 p.e. community that the directive now requires them to remove nitrogen has misread it.

Energy neutrality also starts at 10,000 p.e., and is a national-level target for 2045 rather than something each plant is measured on individually.

Your river is carrying less water than it used to

Using Earth Engine we measured drought at every plant in the register: Palmer Drought Severity Index and catchment runoff, 2022-2025 against the 1991-2020 baseline. 581 plants that carry the tertiary obligation and remove neither nitrogen nor phosphorus today sit in a catchment measurably drier than its own history. Italy 266, Spain 149, Portugal 79, France 73. Widen it to plants missing either nutrient and the figure is 908.

The practical consequence is that a consent based on historic dilution assumptions gets harder to meet without anything changing at the plant. If your permit was written against a flow the river no longer reliably carries, that is worth raising before it is raised with you.

One caution about the register

Population equivalent is a design-load unit, not a flow measurement. Anyone converting your p.e. into a daily volume and quoting it back to you is giving you an estimate. Ask what it was derived from.