Last summer, researchers conducting routine monitoring on the Hudson River began encountering something they had never seen at that scale: a harmful algal bloom extending through a broad section of the river around Kingston. Cary aquatic ecologist Chris Solomon said the concentrations recorded during the event ranked among the highest levels of algal abundance found in the institute’s decades-long Hudson River record. Treated drinking water remained safeAlthough toxin levels in untreated Hudson River water exceeded recreational guidelines at some locations, tests of finished water from municipal treatment plants found very low toxin concentrations, safely below established health guidelines. Another Hudson bloom is likelyNo one on the panel predicted that last summer’s conditions would return every year. But after last summer, no one can assume that a flowing river is immune to harmful algal blooms.