|To Start: Speak to Embir Clearwell in Shrouded Glade.
Embir Clearwell says,"I'm sure the contamination is harmless, but we may not know for days. Merri De'Flor in Lakeshore uses the water for cooking. I wouldn't want anyone to get sick.
Could you let her know that there's a boil order in effect? Better safe than sorry! "
While Embir studies the water sample from Misty Mountain, you should go warn Merri De'Flor in Lakeshore to boil any water before cooking with it.
This is a Search quest.