Bay water temperatures hit 20°C this week, a threshold where petroleum…

June 29, 2026

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Bay water temperatures hit 20°C this week, a threshold where petroleum compounds become significantly more toxic and dissolved oxygen drops sharply. The timing is sobering: the refinery upstream fell into permit violation just as seasonal warming arrived, doubling the chemical stress on water already listed by the EPA as impaired.

The bay has shown real recovery over the past decade — native fish and invertebrates have returned, water clarity has improved. But that recovery and active industrial discharge are now occupying the same system. Warmer water means faster chemical reactions and less oxygen for organisms that evolved in cooler, cleaner conditions. The margin between restoration and fresh damage has never been thinner.

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