West Highland Way Burn Water Sickens 2 Walkers Despite Filters

4 articles · Updated · BBC.com · May 21

Two walkers — a German man last week and an American man on Tuesday — were rescued after drinking from a burn near Conic Hill and becoming so ill they could not walk.
Lomond Mountain Rescue said both men vomited through the night after using straw-type portable filters, with one evacuated from near Rowchoish Bothy to Royal Alexandra Hospital in Paisley.
The team believes the likely source was the Burn of Mar, where agricultural runoff and poorly disposed human waste may contaminate watercourses crossing the popular route.
Rescuers, the national park authority and Scottish Water are urging hikers to use bottled water or known safe fountains, warning that filters alone may not work without boiling or chemical treatment.
The alert echoes similar warnings issued in May 2025 after another cluster of illnesses on the West Highland Way.

If popular water filters are failing, what invisible threats are lurking in Scotland's most famous hiking trail?

With human waste sickening hikers, must national parks now mandate packing out waste to protect public health?

As simple filters prove inadequate, are expensive purifiers now essential gear for even casual hikers?