Walk the loop at Shollenberger Park on any weekend morning and you will pass joggers, stroller-pushing parents, retirees on the benches, and at least one heron standing perfectly still in the shallows. It feels permanent, the way a favorite trail always does. It is not. The 165-acre park that anchors so many Petaluma routines exists today because of a 1970s agreement to dump river mud somewhere, and a report released last year lays out, in detail, how the very ground under that gravel loop is expected to be regraded out of existence over the coming decades.
That is not a headline you will find on the trail apps or the tourism sites. They describe Shollenberger as a fixed destination: two miles of loop trail, a one-mile cutoff to Alman Marsh, a connector to the Ellis Creek ponds, more than 200 bird species recorded along the way. All of that is accurate today. None of it accounts for what the people who actually run this landscape are now planning.
A Park Built to Hold Mud, Not People
The City of Petaluma bought the land in 1970 for one purpose: a place to put dredge spoils, the silt scraped out of the Petaluma River to keep it navigable for boat traffic. That dredging still happens on a roughly four-year cycle. The ponds inside the loop trail exist because they were built to catch and settle that mud, not because anyone designed a wetland park from scratch.
The ecosystem came later, almost as a byproduct. Birds moved in. Native plants took hold along the banks. By 2018, the Petaluma Wetlands, which includes Shollenberger, Alman Marsh, and the Ellis Creek Water Recycling Facility wetlands, had joined the Ramsar List, the global network recognizing internationally significant wetland sites. A place built as an industrial mud pit had become one of the more ecologically notable stretches of shoreline in the North Bay.
The city kept investing in that identity. In November 2024, the Petaluma City Council approved a construction bid for a small amphitheater and educational kiosk inside the park, a 6-1 vote meant to give school groups and visitors a place to learn about the wetlands habitat around them. It reads, in hindsight, like a park settling into permanence just as a much longer conversation about its future was quietly getting underway.
The Plan That Would Erase the Trail to Save the Marsh
In February 2025, the San Francisco Estuary Institute released a restoration concept for the Petaluma Wetlands complex, developed with the city, tribal representatives, and regulators. The proposal covers roughly 484 acres across Shollenberger, Alman Marsh, and the smaller Gray's Marsh to the south, which formed by accident in 1998 when a waterfront berm failed and let tidal water back into what had been diked hay fields.
The plan's second phase, the one that touches Shollenberger directly, calls for completely regrading the park to restore tidal connectivity between the river, Gray's Marsh, and Alman Marsh. A new seasonal pond would go in near the marsh edge. A new ecotone levee would be built on the upland side. The riverfront paths that make the park what it is today, the exact gravel loop people walk every weekend, would be lost in the process.
"We're going to lose Alman Marsh for sure, and will lose parts of Shollenberger Park between now and 2050 to 2075," Petaluma Councilmember and Petaluma Wetlands Alliance President John Shribbs told Bay Nature's Knee Deep Times.
Shribbs also called it "a major landscape transformation," and said it would take "a huge, huge amount of soil movement" to pull off. SFEI Senior Scientist Scott Dusterhoff framed the timeline the same way: conceptual now, with construction realistically 10 to 15 years out if planning starts today, and the report's authors describe the Shollenberger-specific work as something that could stretch toward the end of the century.
None of that means your Saturday walk changes next spring. It means the decision-making process that will eventually decide what that walk looks like has already started, and most of the people using the park today do not know it.
The Timeline, in Order
| Year | What happened |
|---|---|
| 1970 | City of Petaluma buys the land as a dredge-spoils site for river maintenance |
| 1998 | A waterfront berm fails, unintentionally creating Gray's Marsh |
| 2000-2002 | Alman Marsh opens as an extension of Shollenberger Park |
| 2009 | Ellis Creek Water Recycling Facility and its wetlands complete construction |
| 2018 | The Petaluma Wetlands complex joins the Ramsar List of internationally significant wetlands |
| Nov. 2024 | City Council approves an amphitheater and kiosk inside Shollenberger Park |
| Feb. 2025 | SFEI releases its two-phase restoration concept for the Shollenberger, Alman, and Gray's Marsh complex |
| Apr. 2025 | A second community meeting draws 71 survey responses, following 37 from an earlier session |
The Other Fight Over This Same Ground
The SFEI plan is not the first time Shollenberger's future has been contested. A separate community group, Friends of Shollenberger, has spent years opposing a proposed asphalt plant on 39 acres adjacent to the park, a fight tied to a company called Dutra. Their public position, laid out on saveshollenberger.com, is that an industrial plant on that parcel would threaten the same wildlife and river access the wetlands restoration plan is trying to protect. The group has talked about raising money to buy the adjacent acreage outright rather than continue fighting the zoning battle indefinitely.
It is worth sitting with the contrast. One threat to Shollenberger's current form comes from an environmental restoration plan trying to undo decades of industrial use and return the land to tidal marsh. The other comes from a proposal to add new industrial use next door. Locals who love this park are, in effect, defending it on two fronts that pull in opposite directions, and most people walking the loop on a given Sunday have heard about neither.
What Actually Changes This Year, and What Doesn't
Nothing about your next visit to Shollenberger will look different. The dredging cycle continues on its own schedule. The amphitheater and kiosk the city approved in 2024 are still there, built in an area the city itself now knows is part of a decades-out regrading plan. The Petaluma Wetlands Alliance still runs its docent-led tours on Saturday mornings, walking visitors through the same self-guided trail stations that explain how the ponds and marshes work.
What has changed is what's on the record. The SFEI report exists. The community meetings have happened. The survey responses, more than a hundred combined across two sessions, consistently named trail access and shoreline connection as what people care most about preserving, according to SFEI's own account of the process. That gives residents an actual say, but only if they know the conversation is happening.
If you walk this park regularly, or if you are the kind of Petaluma resident who plans a weekend around the loop and the birds along it, the moves worth making now are small. Follow the Petaluma Wetlands Alliance for updates on public meetings. Take one of their docent tours while the landscape still looks the way you know it. Ask the city, when the next community session is scheduled, what "phase one" actually involves in the next ten years, since that is the piece that will affect current trail users long before any regrading near Shollenberger itself.
The park will still be here for a long time. It just will not always be the park you think you know.
I write these Petaluma pieces because knowing the place, not just the market, is most of the job. If you are curious about what a shift like this could eventually mean for property near the wetlands, or you just want someone local to talk through what you're seeing change around your own neighborhood, reach out through Jen Birmingham. I'm always glad to talk Petaluma, whether or not a transaction is anywhere in the picture.
