The Petaluma River is in good health, experts say, and cleanups help keep it that way

Those living near – or floating on – the muddy Petaluma River may be surprised to hear what local experts have to say about its ecological health.

The beloved waterway, they say, is in pretty good shape. In fact it’s considered the Bay’s cleanest estuary – so clean that salmon are happily spawning in it.

The “relative health” of the Petaluma River’s ecosystem has been, and remains, “really good,” said Petaluma High School marine science teacher Phil Tacata. He said colleagues and fellow marine science experts – including educators at both Petaluma and Casa Grande high schools who conduct regular water quality tests with students – support that assessment.

And the best thing people can do to keep it that way, he and others said, is to keep trash out of it. Locals will get a chance to do that at the 2023 Fall River Cleanup event this Saturday, Sept. 23, starting at 9 a.m. at Steamer Landing Park in Petaluma.

Tacata said Casa Grande High School teacher “Dan Hubacker, in particular, is out on the Petaluma River with his students every fall collecting data for the National Marine Fisheries Service on a viable, continuously reproducing population of wild Chinook salmon right here in our Petaluma River. Very cool work.”

Hubacker, who teaches environmental conservation and restoration at Casa Grande and is director of the school’s United Anglers program, was not immediately able to comment on the data his students have collected.

Tacata also credited Petaluma High’s AP environmental sciences teacher Kris Camacho, who does annual water quality tests on the river with her students, for making similar findings.

The presence of Chinook, he said, is a good indicator of the watershed’s health.

“Salmon are a particularly environmentally sensitive fish and need excellent water temperature, high oxygenation, appropriate particulate turbidity, and low toxicity to survive, and the fact that we have a viable wild salmon population here in Petaluma supports that our watershed is pretty good,” he said.

Stephanie Bastianon, executive director of Friends of the Petaluma River – the organizer of this Saturday’s cleanup efforts in Petaluma – said many people wonder about the local waterway’s ecological health.

“We field a version of this question often,” she said. “Many people assume, because of the brownish color of the river, that it is polluted. However, the coloration is due to the fact that the river is a brackish river, a mixture of fresh and saltwater with a lot of sediment flowing as the tides carry water in and out of the river from San Pablo Bay.”

She added, “The Petaluma River is also home to the largest ancient tidal marsh in California, which helps filter pollutants and absorb floodwaters. Our wetlands will play a huge role in our resilience to climate change and sea level rise.”

Tacata touched on that as well, noting that Shollenberger Park is another “healthy estuarine zone,” and that such places provide protection from sea level rise and flooding “due to the sponge-like absorption” they are capable of.

The Petaluma River is not a river – it’s an estuary, a finger of the Bay that is fed by tidal waters as well as freshwater streams during winter rains.

It is known to be the northernmost estuary of the entire Bay system, extending to the northern edge of Petaluma. What’s less well known, perhaps, is that it is also the Bay’s cleanest estuary.

Tacata said he’d be bringing more than 30 student volunteers to help keep it clean on Saturday.

Friends of the Petaluma River, he said, has “done a fantastic job of keeping trash and plastics out of our river” thanks to “major cleanups like the one Friends is organizing (this) Saturday.”

Don Frances is editor of the Petaluma Argus-Courier. Reach him at don.frances@arguscourier.com.