Can water go bad if not refrigerated?

Water itself doesn't spoil or go bad in the same way food does, but it can become contaminated or develop an off taste if left unrefrigerated for extended periods, especially if stored in unsealed or dirty containers. Bacteria and algae can grow in water that is exposed to light or air. To maintain its quality, it's best to store water in a cool, dark place and in clean, sealed containers. If water has been stored for a long time or shows any signs of contamination, it's safest to discard it.