Slow Sand Filters - Loren Oki
Physical and Chemical Control Options of Pathogens in Water Recycling Systems - Donald J. Merhaut
Retention Pond and Chlorine Oxide Treatment
Water Quality Indicators
Water Quality Indicators Playlist
https://www.youtube.com/playlist?list=PLzSpUZOE1aiOzYg6FBvTdDn-rhDjHVhCg