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.
Our team of industry professionals 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.
What is Clamshell Dredging?
Clamshell dredging is a clam-shell-shaped bucket that opens and closes to grab and remove sediment underwater, ideal for collecting sediment in deep waters and hard-to-reach areas. The bucket is lowered into the water to grab or “clamshell” sediment at the bottom of the river. Then, the collected sediments are lifted up and deposited in to a barge where it can be hauled away and disposed of properly.
The bucket often hangs from a crane that is mounted on a barge. Alternatively, it can be mounted on a excavator. Clamshell dredging is used to create means of safe travel for cruise liners and cargo ships due to its utility in deep water. Clamshell dredging differs from backhoe dredging, which has a shape like a half-open shell and is used in shallow waters.
Dredging Petaluma River Reaches 6, 7, and 8
Pacific Dredge and Construction, LLC (PDC) 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 our PDC 180 barge, Manitowoc 4600 crawler crane, and Cable Arm 17 cu yd 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.
‘S. Bass’, ‘Cadet’ and ‘Admiral’ Tugs Perform Valuable Service
Pacific Tugboat Service (PTS) brought out their best and most powerful tugs to aid in the Petaluma River Channel maintenance dredging project. The tugboat “S. Bass” towed Pacific Dredge’s 2,000 cubic-yd capacity scows to the in-bay disposal site in San Pablo Bay. PTS supplied our truckable tug “Cadet” and assisted tug “Admiral” to help with the massive job.
Steven R. Bass received the Navy Cross in 2001 after leading the rescue attempt at an Afghanistan prison compound. Named in Master Chief Special Operator Bass’s honor, this reliable tug pushes large barges from San Francisco to San Diego.
Truckable Push-Tug Cadet
The Harbor Cadet is one of PTS’s fleet of small truckable push-tugs. This versatile and compact machine can be placed on barges or trucks and delivered to wherever they are needed.
An even more compact push-tug, the Harbor Tug can maneuver easily in tight spaces. A valuable part of our Harbor Tug Fleet, the Harbor can fit between piers and ships to tow and assist in spaces others cannot access.
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.
Contact Pacific Maritime for More Information
At Pacific Maritime Group, we have been a leader in the dredging industry for many years. We take great pride in being a respected leader in professional mechanical and hydraulic dredging services from Mexico to Alaska. For complete information, contact Pacific Maritime Group today.