A decade of bathing water classifications in Greece and Croatia

This note follows the share of sites classified "excellent" in Greece and Croatia across every season in the history dataset — Greece from the first year of the current EU classification scheme in 2011, Croatia from 2012. Every value below, and every point on the chart, comes straight from that published table, not from a separate calculation done just for this note.

A decade of mostly-excellent water

Every share in this chart is a share of classified sites that season, not of every site in the network — the same correction the companion note on the 2025 snapshot explains in full. Leaving unclassified sites in the denominator would make a growing network look like it's getting worse, when nothing about its water has changed.

In Greece, 95.1% of classified sites were excellent in 2011, the lowest point in the whole series; the share climbed over the next few seasons and has stayed in a narrow, high band ever since, reaching 97.5% in 2025 (with 0.4% of all Greek sites still not classified that season). Across the fifteen seasons, the line in the chart above never strays far from the top.

Croatia's series is steadier still: 96.7% of classified sites were excellent in 2012, and the share has sat close to that level every season since, including 96.8% in 2025. That 2025 figure already accounts for a real change behind it — Croatia's monitoring network grew substantially that year, and 10.9% of all Croatian sites that season don't have a class yet, far more than in any earlier year, because a newly added site needs several seasons of history before the directive's method can rate it at all (the companion note on how classification works explains why). Counted against every site instead of only the classified ones, 2025 would look like a sharp dip in Croatia's water quality; it is not one, once the sites that simply don't have a rating yet are set aside rather than counted as failing.

Read together, the two series are a reminder that a single year's share is only one point on a much longer line, and that the size of the denominator matters as much as the number on top. Both countries' decade-long stability is visible precisely because the history dataset keeps every past season's classification alongside the current one, rather than overwriting it each year.

Reading the chart

The chart's vertical axis runs from zero to full marks, not zoomed to the range of the data, so the visual slope doesn't exaggerate differences that are, in percentage-point terms, fairly small. The exact figure for every year and country is in the table beneath the chart, for anyone who wants the numbers rather than the shape of the line, and for any crawler or screen reader that can't read an SVG line chart at all — the table carries the same data in a plain, accessible form.

What this is, and isn't

Both series come from the same rolling, multi-season evaluation described in the companion note on classification: a site's class in any given year already reflects several seasons of monitoring, not just that one year. This note describes what has already happened in the published history; it makes no claim about where either country's share goes from here, and it does not compare either country against bathing water outside this catalog's dataset. As with every page in this catalog, a classification is not a same-day safety assessment — check local signage and authorities before swimming, not a chart.

Sources and further reading

• Dataset: EU bathing water classification history — Greece and Croatia — schema, downloads (CSV and JSON), and the full EEA attribution.
• How classification works: How EU bathing water is classified — the four classes, and what "new" and "not-classified" mean.
• The 2025 snapshot: Greece vs Croatia: bathing water quality in 2025, in numbers.
• Related: Bathing Water Index (water.wldlogic.com) publishes individual site pages built from the same data.