In 2022, 7.69% of individual lead measurements in Waternet's distribution area exceeded 5 µg/l. By 2024 the share was 3.88%, according to the Human Environment and Transport Inspectorate, below its 2019–2023 average of 5.71%.
A steady fall
The 2023 figure, 5.80%, sat between the two. In 2022 no measurement exceeded 10 µg/l, against an average of 2.38% above that level over 2014–2021. The Inspectorate's tables list 6 notified exceedances by Waternet in 2022, 2 in 2023 and 3 in 2024. In 2022 the annual average nickel concentration in the Amsterdam distribution area did not meet the standard, because of elevated results at 3 separate premises.
Clean at the plants
At Waternet's two production sites the 2025 results were clean on microbiology. All 730 E. coli measurements and all 104 enterococci measurements at each of Leiduin and Weesperkarspel were 0 cfu/100 ml.
What still shows up
PFAS is present but below the new limit. The sum of 20 EU PFAS averaged 23 ng/l at Leiduin and 19 ng/l at Weesperkarspel in 2025, against a standard of 100 ng/l in force from January 12, 2026. Waternet has spent €1 million a year extra since 2022 to filter PFAS and argues for tackling it at the source. Sulfamic acid exceeded its 1 µg/l standard in every Leiduin measurement and in 12 at Weesperkarspel, and four chlorate results at Leiduin were above 1 µg/l; all were reported to the Inspectorate.
How Waternet's quality results sit alongside its finances, its 2026 tariff of €2.09 per m3 and its capacity plans after 2030 is set out in the reference profile. The full report, Utility Intelligence Profile: Waternet, is available for USD 99. For a free overview, read the Waternet Utility Snapshot.