For 16 days this year Yass Valley residents were ordered not to drink the town water during a boil water alert, and local doctors say general water quality remains a major concern for people and their health. For 16 days this year Yass Valley residents were ordered not to drink the town water during a boil water alert, and local doctors say general water quality remains a major concern for people and their health. Water Pollution, Local Government, Water Supply, Water Management Latest business news