Wonders of Water Science Project - Making Clean Water: After learning about pollution and water conservation, you could have your Brownies split into groups and make clean water that has been "polluted" with dirt and other sediments.
water - purification - Safe, Purified Water for Home, Camping, and More - The award-winning, world-renowned LifeStraw Family large volume water filter can filter out viruses from an incredible liters of water
Quick Guide to Berkey Water Filter Contaminant Removal
LifeStraw offers easy access to clean and safe drinking water anywhere! A Time Magazine "Invention of the Year" winner, LifeStraw is the most advanced, compact, ultralight personal water filter availa (Survival Water Filter Products)
Sawyer Mini Water Filtration System - Drink straight from a puddle or stream with the filter or from the enclosed bag after filling it from a stream or pond. Does up to 100 000 gallons. Back flush to clean filter with syringe supplied