Petaluma River Channel maintenance dredging project

In a continuing project designed to open up the Petaluma River as a viable recreational and commercial waterway, Pacific Dredge and Construction LLC performed a second substantial dredging job commissioned by the United States Corps of Engineers.

The crews used powerful mechanical clamshell dredging equipment to remove and dispose of mud and silt that lined the bottom of the main artery for this once-vibrant river community.

Pacific Dredge and Construction had previously used hydraulic dredging equipment in reaches 1-5 to remove more than 190,000 cubic yards of sediment along an 18-mile thoroughfare linking Petaluma to the San Pablo Bay.

Reaches 6, 7, and 8 required clamshell dredging from the Petaluma River’s mouth to the middle of San Pablo Bay using a dredging depth of -8 MLLW, with two feet of allowable over-depth.

The Petaluma River dredging project’s latest reaches were mechanically dredged using the company’s PDC 180 barge, Manitowoc 4600 crawler crane, and Cable Arm 17 cubic yards environmental clamshell bucket.

Approximately 57,000 cubic yards were dredged and disposed of at the approved in-bay disposal site (SF-10) in San Pablo Bay.

Pacific Tugboat Service (PTS) brought out their best and most powerful tugs to aid in the Petaluma River Channel maintenance dredging project.

Future of Petaluma River

The Petaluma River had not been dredged since 2003 and was passable only at the highest of tides. The dredging and towing work performed by the Pacific Maritime Group is expected to help clear a return to water traffic and business for a community hit hard by the coronavirus pandemic.

While officials look forward to a resurgence, the project is expected to provide the river community, a four-year dredging cycle is needed to maintain an ongoing clear passageway.

Photo: Pacific Dredge and Construction