Czech reservoirs face deteriorating water quality and swimming bans

The Plumlov Reservoir in the Olomouc Region has seen its water quality fall to level 3 on the five‑point scale, indicating a higher probability of health problems for swimmers. Hygienists have increased sampling to every 14 days because of repeated cyanobacteria blooms, and a swimming ban that was first announced on 4 August last year remains in effect as water quality typically worsens in midsummer due to phosphorus runoff.

In South Bohemia, the Podolsko area on the Orlík Reservoir was rated the worst – level 5 – leading to a temporary ban on bathing that continues. Nearby sites such as Radava, the Hejtman and Staňkovský ponds, and beaches on the Lipno Reservoir received excellent (level 1) or good (level 2) ratings. Regional health stations conduct bi‑weekly water tests and issue bans when cyanobacteria exceed legal limits.