This document discusses various water filtration methods like distillation, ultra filtration, and electrodialysis. It then focuses on biosand filters, which provide clean drinking water through a simple design using sand and gravel. The document describes Clean Water for Haiti, a non-profit that works to provide sustainable water solutions in Haiti, where over 5 million lack access to clean water. It provides details on volunteer trips to help with their efforts and images showing Haiti's water challenges.