onWater — Toxic Algae Watch

onWater · Toxic Algae Watch

Bloom severity

Tap a water for a safe-to-fish read. Search any US lake or river — report a bloom →

⚙ Advanced view

Map layer

🌡️ Regional heat view

🛰️ Satellite imagery

Severity filter

✕Danger · no contact HHigh · warning MModerate · caution LLow / clear

Toxin type

Nowobserved

Now+1+2+3+4 wk

No waters match these filters.
Try turning a severity or toxin back on.

📍 Tap the map where you saw the bloom

Report a bloom — where?

Find the waterbody

or

📍 —

What did you see?

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Email me about this water

We'll email you when the bloom status of this water changes. Production sends via onWater transactional email (Braze).

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