With a clear plastic bottle and some heavy duty aluminum foil, you can purify water from any natural source with solar radiation.
Put the water into a clear plastic water bottle and place it on top of the aluminum foil or another highly reflective surface. Leave the bottle in direct sunlight for at least 6 hours (2 days if it’s overcast) and the UV rays from the sun will drastically improve the quality of the water. Perfect for emergency water purification.
This method only works for clear water and doesn’t filter out solid contaminants so if needed, clarify water first.