The map

Reading it

• Bathing waters are coloured by today's verdict: darkest red do not swim, a lighter red advice against bathing, amber take care, green no warnings, hollow means something could not be checked.
• Waterfalls are blue, and the stronger the blue the more rain has fallen near one in the last two days. Grey means nothing has been measured there. They carry no water quality information at all — nobody tests them.
• Storm overflows shows the monitored outfalls within 2km of a bathing water: red where one is discharging right now, amber where one discharged recently, green where a monitor is reporting and not discharging, and a dashed grey ring where a monitor is not reporting at all — which says nothing about what that pipe is doing. Nothing appears in Ireland or Northern Ireland: the Republic publishes no storm overflow data at all, and Northern Ireland publishes a yearly summary rather than a live feed. An empty stretch of coast there means nothing is published, not that nothing is discharging.