‘The hope we had is gone’: how 20 months of stasis has paralysed Northern Ireland

Algae thriving on Lough Neagh, which supplies 40% of Northern Ireland’s drinking water, can be seen from space. Photograph: Liam McBurney/PA

It is a grim milestone for Northern Ireland that some of its problems are now visible from space.

A vast blue-green algae is choking Lough Neagh, which supplies 40% of Northern Ireland’s drinking water, owing to excessive farm slurry, human sewage discharges and other management blunders.