The latest on the unprecedented Hudson algal bloom
October 10, 2025
Over the next week, Riverkeeper and our partners will be collecting samples and monitoring water quality in the affected areas (roughly Germantown to Poughkeepsie) using Riverkeeper’s boat. Evidence suggests the intensity of the bloom has decreased compared to previous weeks. However, the most recent observations suggest recreational users should continue to exercise caution and avoid water contact in the affected areas. Tap water for those supplied by the river remains safe, thanks to the vigilance of the Hudson 7 water plant operators.
Watch Riverkeeper’s recent Learning Session to learn about what harmful algal blooms are, why they matter, and what the bloom in the Hudson tells us about the river’s health.
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