Featured Project Archives - The Dutra Group

Emergency Feather River Dredging and Debris Removal

Admin — Fri, 01 Dec 2017 09:46:47 +0000

Project Description

Record storms battered Northern California in early February 2017, leading to historic flows into Lake Oroville, coupled with severe erosion damage to the Oroville Dam main spillway resulted in the emergency spillway being used for the first time in history. Erosion damage below the emergency spillway forced Dam authorities to release flows up to 100,000 cubic feet per second through the damaged main spillway in an effort to avoid a potential collapse of the spillway and catastrophic downstream flooding. The release through the damaged main spillway and emergency spillway resulted in the erosion of millions of cubic yards of debris into the Feather River.

The San Rafael Rock Quarry, Inc. – SRRQ (a Division of The Dutra Group), was called upon to lead a marine-based approach to removing debris from the river, and within 24-hours our workforce was onsite planning and implementing the mobilization of workers, equipment and resources to begin clearing the debris.

Within 10 days, over 200+ truckloads of equipment were mobilized, and a staging/ offload facility established at the Thermalito Diversion Pool, SRRQ was ready to commence dredging when the Department of Water Resources shut down the massive spillway flows. Working in conjunction with other contractors, over 1-million CY of debris was removed from the river during the first spillway shut down period allowing flows to resume from the Hyatt Power Plant.

Project Scope
Mobilized 3 dredge barges, 9 material transport barges, 7 tug/workboats, support vessels, 300’ bulkhead offloading facility, a crane loadout & vessel haulout/repair facility, a crew & equipment support camp, haul roads, and a disposal stockpile;

Working with other contractors, removed over 1.68 million CY of material as of May, 2017, and stockpiled for beneficial use;
Working 24/7 shifts, with over 100 personnel, accommodated periodic work shut downs due to DWR spillway releases;
Provide onsite 24/7 river rescue crew, onsite safety and first responder medical facilities, crew mess hall, office and meeting facilities;
Provide hydrographic survey & quantity calculations for DWR and in-house planning..

Major Challenges
Five different safety meeting locations needed to be held daily with over 60 crew members, 30 pieces of equipment to address the safety challenges of unloading and assembling Flexifloat barges, heavy equipment and crane barges, loading of forklifts and then floating all up river and under the Railroad Bridge. Implementation of JHA & Swift Water Rescue Boat team due to swift water near staging areas.

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Naval Base San Diego, California, Maintenance Dredging

Admin — Thu, 01 Dec 2016 09:45:03 +0000

Project Description

Maintenance dredging of 5 NBSD Piers. Processing approximately 47,000 cy of dredge material containing radiological objects and munitions and explosives of concern in an upland confined drying facility. Dutra designed a facility to handle identifying and isolating RO’s and MEC objects and tracking them through manifests. Once the final gamma walkovers indicated that all objects were isolated and removed, The Naval radiological compliance agency RASO approved the Gamma data from each 2,000m2 pad so Dutra could truck that material off to a local land fill. Managing a subcontractor certified in handling radiological objects and munitions and explosives of concern was crucial piece of the project.

Major Challenges

There was a major risk taking on a guaranteed unit price in this design/build project.

The award schedule was pushed to the 11th hour. We had a very short window to complete this project.
We had to test and develop methods quickly and successfully in a very short time.
This is a design/build unit price project. One of the first for a project like this so there was no pre-existing map or template to develop the project by. We developed all the processes and methods to complete the project on site. It took a lot of research and skill. It took a lot of oversight and management involvement. The RWP (radiological work plan) and ESS (explosive safety submission) included a lot of involvement of controls that took a lot of coordination to successfully complete this work.

Project Scope

The scope of all the processes involved started with dredging the impacted areas. That material had to be loaded through two screening processes on two barges. The final dredge screening was a 3” grid. The material was then relegated to a much smaller explosive arc that could be easily managed in the confined drying facility where it was offloaded. That initial wet mud was then treated with quicklime to facilitate quick drying. When the material was dry enough it was put through a 3/4” power screen. That process as well as the larger 12” and 3” screens on the scows created a debris stream that was checked for RO’s and MEC. The screened material was then laid out on pads with very specific dimension requirements. A sensitive gamma walkover instrument was then towed across every inch of those pads to determine if any small RO’s went through the screens. Once those gamma walkover data packages were developed, they were sent to RASO for approval. Once approved, the pads are stripped and the material was trucked to a local landfill. The debris was checked by hand, all MEC was either demilitarized or blown up. The radiological objects we put into sealed and manifested drums to be transported to a proper receiving facility.

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North Bay Operations and Maintenance Facility, Napa, California: Waterside Construction and Passenger Float Project

Admin — Fri, 01 Jan 2016 09:46:21 +0000

Project Description

The project consisted of designing and constructing new berths for ferry vessels to accommodate maintenance and passenger service activities. The berths are comprised of precast concrete floats with a steel superstructure to match the vessel freeboard in addition to a re-furbished steel hull service float. All floats are secured in place with driven steel pipe pile. The project also included fabricating a new spare steel hull passenger loading float that can be utilized at multiple WETA facilities in the bay.

Major Challenges

One of the major challenges faced by the design-build team was the design, fabrication and launching of the concrete floats. The challenge was designing the concrete floats so that they could be lifted and lowered into the water using the equipment provided by the pre-caster. KPFF, Dutra, and Kie-con worked collaboratively to create a quality float design that was cast monolithically. Another major challenge was coordinating the multiple final designer’s efforts coupled with multiple bridge designer’s product. The challenge was overcome through partnering communication and collaboration.

Project Scope

Install 23 steel pipe piles ranging from 24” to 42”.
Fabricate and install 6,185 sf of concrete floating docks.
Drydock and modify existing 4,080 sf steel Service Float.
Install landing platform and 90’ gangway.
Install power, lighting, and mechanical systems.
Fabricate and install steel superstructure with 2 movable ramps for passenger loading.
Fabricate new steel hull passenger float.

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Marina Del Rey, California, Harbor Maintenance Dredging

Admin — Sat, 01 Dec 2012 09:32:28 +0000

Project Description

The $11 million Marina del Rey harbor maintenance dredging project involved the removal of 800,000 cubic yards of material from the entrance to Marina del Rey and the repurposing of 75,000 cubic yards of sand to re-nourish Redondo Beach.

The project was segmented into 8 areas. Each area having been tested for compatibility with, nearshore disposal, beach nourishment, or placement at the Port of Long Beach.

The harbor entrance had shoaled significantly since the previous dredging episode.

The immediate need was to open the harbor entrance for first responders stationed in the marina. The other goals of the project were to remove material not suitable for ocean disposal, create two sand traps to extend the life of the project and use beach compatible sand to re-nourish local beaches.

The material that was deemed non compatible for ocean disposal was taken to the Port of Long Beach and utilized for their middle harbor expansion project. This operation required close coordination with the engineers at the Port so that they got the sand with the desired geo characteristics placed at specific locations and elevations within the fill site.

The final task of the project was to place 75,000 cubic yards of sand dredged from Marina del Rey along a 1,300 foot stretch of Redondo Beach. This operation required two dredges, two tugs, and three scows plus equipment and crew on the beach.

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Eden Landing – Tidal Restoration

Admin — Wed, 01 Dec 2010 09:45:53 +0000

Project Description

The Project was Phase I of the San Francisco South Bay Pond Restorations Project, which will ultimately restore 15,000 acres of former salt ponds to managed tidal wetlands. Phase I involved the restoration of 950 acres, with the goal of providing enhanced habitat for plant and wildlife species including the endangered Clapper Rail and Salt Marsh Harvest Mouse. The existing levees were constructed with dredged materials, underlain with Bay Mud, resulting in poor overall structural conditions.

Major Challenges
The project involved working with endangered species restrictions and coordination with other contractors working simultaneously with the project site.

Project Scope

Execute dredging operations within a sensitive tidal creek.
Removal and improvements to dilapidated levees.
Construction of new levees and berms.
Excavation of channels and levee breaches.

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Cabrillo Way Marina, California, Rehabilitation

Admin — Mon, 01 Dec 2008 09:31:03 +0000

Project Description

As the first new marina to be built in Los Angeles in over 22 years, the Cabrillo Way Marina port rehabilitation created a vibrant village atmosphere for recreation and boating activities. Covering 49 acres of land and 37acres of water, this award-winning project is a showcase, state-of-the-art port based on green design and sustainability.

Major Challenges

To accommodate environmental concerns, piles were driven using a vibratory hammer that minimized disturbance at the ocean floor, and in surrounding habitats. Specialized off-road equipment was employed to meet Tier 2 off-road emissions standards, and on-road heavy-duty diesel trucks were used to comply with strict EPA emission standards. Construction work adjacent to existing facilities and in an operating harbor created a challenge for careful construction methods and phasing.

Project Scope

Dutra was responsible for construction and demolition of all marine portions.
Remove existing shoreline armor rock and recycle for reuse on-site.
Dredge 180,000 cubic yards and place in an upland facility.
Place 130,000 tons new base and armor rock.
Install 650 24” octagonal piles.
Fabricate and install 270,000 square feet of floating concrete docks.
Install 5,000 linear feet of combi-wall sheet pile retaining wall.
Install electrical and mechanical throughout the marina.

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