River Dredging Schedule & Info


The much anticipated US Army Corps Petaluma River Dredging project is finally here!

As with all major renovation projects, the dredging work will create some pain--including traffic and park closures--before we get to our ultimate gain--a better River! The good news is, most of the impacts will occur for a short time, not for the entire project timeline.

This project is being funded and managed by the US Army Corps of Engineers. But it is only happening because of the hard work and determination of countless community members, local and national leaders, and partner organizations. We appreciate your patience during this final part of our dredging journey!

Get more details about the dredging project in the resources and FAQs below.

Funding Announcement Press Release
Capital Improvement Projects Page (Engineer information)
Staff Report

Project Manager

Jonathan Sanglerat

[email protected]


Project Hours of Operation & Timeline

The dredging crews will be working 24 hours a day, 7 days a week, from September 4 through October 21. This expedited project timeline is required by the US Fish & Wildlife Agency permit required by the project. Working 24x7 will help protect our local ecosystems!

Update on Dredging Status of Marina

In response to questions about the status of dredging of the Marina, the Marina will be dredged, however, not as part of the current dredging project.
Dredging the Marina requires a different approach - mechanical instead of hydraulic. The current project used a hydraulic approach that is not suitable for the Marina. The City is working to get the required permits and identify the needed funds to dredge the Marina, using the mechanical approach, as soon as possible.

Shollenberger Trail Loop Closure Aug 31-Nov 1

For the work to be completed, the Army Corps of Engineers requires that the popular Shollenberger Loop Trail be CLOSED from Monday, August 31 through Sunday, November 1. The closure includes the main parking lot and public restrooms located off Cader Lane.

We understand that closing this popular section of trail will undoubtedly be an inconvenience for many. We encourage all those looking to access the local wetlands to take advantage of the network of trails that will remain open at the Ellis Creek Water Plant (parking lot off of Cypress Dr.) and Alman Marsh (parking at the Sheraton Hotel).

Noise Impacts Oct 11 through Oct 21

Dredging is noisy work! Residents and businesses along the Riverfront may experience noise when the project moves into the Turning Basin (Oct. 11 through Oct. 21). Remember, dredging will happen 24 hours a day, 7 days a week. Please be prepared for noise all day and all night. Thank you for your patience!

River Access

During the project, the areas undergoing dredging will not be accessible to the public, and marine traffic will likely be affected as well. Obstructions such as docks that are currently encroaching on the federal channel will need to be relocated during the project.

Dredging will begin on Friday, September 4, 2020, and will end no later than October 29, 2020. Under the terms of the contract, the contractor has 89 days to complete the project.

The contractor is allowed to work 24 hours a day, 7 days a week. This is a big project with a short timeline so we expect to see crews working day and night, 7 days a week.

Important information about D Street Bridge Closure

The US Army Corps of Engineers is responsible for funding and managing the dredging project. The City of Petaluma is a partner agency on this project; however, we are not managing this project and have not been part of the decision-making in terms of the contractor chosen, project timeline, or hours of operation.

Dredging will begin at Shollenberger and then work downstream (towards the Bay) to address some spots of shoaling along the channel. Once that is complete, work return to Shollenberger and then go upstream (towards the City core), finishing with the Turning Basin.

Important Info about D-Street Bridge Closure Oct. 4 – 11.

The dredging project will have the following impacts:

Shollenberger Park Access
The loop trail around Shollenberger will need to be closed for the duration of the project, to allow safe equipment access and to help ensure public safety.

Dredging can be noisy work. Those who live and/or work along the river should be prepared to hear noise (similar to heavy construction work) 24 hours a day, 7 days a week. The noise will be most apparent from mid- to late-October, when dredging occurs along the City’s River Front and downtown areas.

Vehicle Traffic
When dredging occurs in the Turning Basin, the D Street Bridge will be opened multiple times a day, thereby, impacting the traffic along D Street.

Access to the Petaluma River/Boat Traffic
During the project, the areas undergoing dredging will not be accessible to the public, and marine traffic will likely be affected as well. Obstructions such as docks that are currently encroaching on the federal channel will need to be relocated during the project.


Over the past decade, silt has built up in the Petaluma River, making it impossible for tourists and locals to boat down the river, whether as part of a day’s excursion for shopping and lunch in Petaluma or as part of one of the many water-based events such as the Holiday Lighted Boat parade.

Removing this silt through dredging will result in a deeper river that will accommodate a wide variety of boats. This means more recreation opportunities, the return of river events, and a revitalized riverfront economy and experience.

Dredging also will offer more flood protection.

The City has been pursuing additional funding and project partners to make a push for beneficial reuse of the dredge materials. Beneficial reuse could include the use of the dredge material to enhance the resiliency of the Petaluma Marsh and help protect additional vulnerable locations along the Petaluma River.

This project is following strict Fish & Wildlife protocols and other measures to protect the environment.

Project Timing & Deadlines
The US Fish & Wildlife Agency has issued a permit for this project, with the condition that the project be completed during a certain time of year and within a certain time frame. The project must run on a 24×7 operation in order to meet these permit requirements.

Water Quality Tests
California Regional Water Board – San Francisco Bay Region issued Waste Discharge Requirements for this project. These include requirements for sampling and observation through and a self-monitoring program conducted by the City’s Water Quality team.

Safe Silt Disposal
Dredged material will be disposed of at a designated disposal site in the Bay.

The work in this Upper River portion will be completed with a 74’ suction dredge, Sandpiper. A 24” pipe will be connected to the dredge and material will be pumped through the pipeline into the Shollenberger disposal site. The longest length of pipeline will be ~14,000 ft when the dredge is working in the turning basin.  The pipeline will be submerged for most of it’s length but marked with buoys.

At the disposal site in Shollenberger, a bulldozer and other equipment will be used to spread the material as needed and reposition the discharge pipe.

There will be a second, clamshell dredge that will be removing material ‘out in the flats’ from the channel in San Pablo Bay.  This material will be loaded into a hopper barge, which will dispose of the material  at a designated in bay disposal site.

The City of Petaluma is wrapping up the process for obtaining 10-year maintenance dredging permits to support future maintenance dredging events, including the tentatively scheduled Marina dredging in 2021. The City will also be applying for the Measure AA Grant to provide additional funding for upcoming dredging. In addition, the City has been pursuing additional funding and project partners to develop a long term, sustainable plan to have the Marina regularly dredged

Turning Basin
map of Petaluma River Dredging project
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