Engineering Disciplines


Services

Hydrographic Surveys

Hydrologic & Hydraulic Feasibility Study, Phase II, Bel Marin Keys, CA.

NCI is currently under contract with the Corps of Engineers (San Francisco District) to perform on-call design services for navigation and water resources projects. The Phase II study for the Bel Marin Keys V Wetland Restoration project is part of the overall Hamilton Wetlands Restoration and the work order is to perform an assessment of hydraulics, hydrodynamics, and sediment movement in Novato Creek located in San Francisco Bay. The tasks include bathymetric survey in Novato Creek, deployment and retrieval of tide gages and current meters, and hydraulic & hydrodynamic numerical simulations. The hydraulic simulations are to assess the potential impacts to water levels at various reaches of the creek under 19 different scenarios of flood and project improvement conditions. The tidal-induced estuarine hydrodynamic modeling is to characterize water level and currents throughout the Lower Novato Creek so as to address any potential shoaling and scouring impacts resulting from the proposed Bel Marin Keys V wetland restoration.

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Hamilton Wetlands Restoration Project, Novato, CA.

NCI is the prime A/E contractor for a series of jobs for the San Francisco District Corps of Engineers on the Hamilton Wetland Restoration Project. This is a project to convert over 500 acres of a decommissioned army airfield to a wetland restoration area using dredged spoil material. The area will consist of seasonal and tidal wetlands. NCI has worked, or is working on 4 separate deliver orders under 2 separate IDIQ contracts. These consist of:

  1. Topographic mapping of the site using aerial photography, bathymetric surveys and land surveying to be used for planning, design and preparation of contract documents for design of all project features.
  2. Land surveying, geotechnical review, design, cost estimating and preparation of contract documents for the Bulge Levee and the Pacheco Pond Levee. These levees perform containment for a portion of the seasonal wetland. Design features included a ramp over the levee for construction and future access, tying into the existing Pacheco Pond Levee, using onsite borrow material, drainage, a road base, and demolition of existing facilities. MCACES was used to prepare the cost estimate. SPECSINTACT was used to develop the specifications. A SWPPP was prepared for the project.
  3. Additional design and preparation of contract documents for the N-1 Levee and Containment Berm to complete the perimeter of the seasonal wetland. Similar design services were provided for the Bulge Levee. Critical design issues included minimizing potential impact to an adjacent forced main sanitary sewer line. Both the Bulge Levee and N-1 Levee delivery orders were completed on an expedited schedule.
  4. Bathymetric surveying and numerical modeling to evaluate the effectiveness of and impacts from the wetland restoration project. This involved numerical simulations of hydrodynamics and sedimentation in the project area that includes both Novato Creek and the to-be-restored wetlands.

NCI is currently under contract with the Corps of Engineers (San Francisco District) to perform on-call design services for navigation and water resources projects. The largest design project to date is for the Hamilton Wetlands Restoration Project, which will be used as an upland dredged material disposal site until the restoration goals are achieved. This project involved the mapping (aerial topography, land surveying, and hydrographic surveying) of the site and surrounding areas and the detailed design and preparation of construction documents for two levees (3,240 feet long) to contain pumped-in dredged material. The owner is the California Coastal Conservancy, however the work was performed under contract to the San Francisco District Corps of Engineers. The work included evaluating potential onsite borrow areas, demolition of a hydraulic siphon system, design of a culvert through the levee for storm water flow, design of an access ramp over the levee suitable for construction equipment, connection to an existing levee, design of the levee cross-section to maintain clearance to the property line for a maintenance road and to provide a varying slope for aesthetics, and design of an aggregate base road surface. Quantity computations were performed, a SWPPP was prepared, SPECSINTACT was used to prepare contract specifications, and MCACES was used to prepare the engineer's cost estimate. The design project was completed under an expedited time schedule.

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Comprehensive Coastal Sand Management Plan, Santa Barbara/Ventura County Coastline, CA.

B.E.A.C.O.N. is a joint power authority consisting of the Cities of Port Hueneme, Oxnard, San Buenaventura, Carpinteria and Santa Barbara, and the Counties of Ventura and Santa Barbara, which was established to seek solutions to reestablish their eroding shorelines. NCI's study included the inventory of offshore, harbor entrance and fluvial sand sources; estimating erosion rates and sediment budgets; preparing a comprehensive sand management program to control beach erosion; and recommending and implementing an effective monitoring plan to observe indicators of beach health within the Santa Barbara and Ventura County coastline. A field program of seismic profiling, dart coring and vibracore sampling was performed to identify favorable sand deposits that exist within close proximity to beaches in need of nourishment. The flood levels and erosion rates/sediment budget were developed using numerical wave and sediment models, aerial photographs and surveyed beach profiles. Twenty-five beach profile stations covering the 60-mile study coastline were established, with two sets of bathymetric surveys performed along these transects. This study included evaluating potential dredging equipment, and methods and costs to perform large scale beach nourishment. Environmental, economic and cost-benefit evaluations were also performed. The final report recommended three alternative levels of a coastal sand management plan and included several demonstration projects. Funding opportunities are being explored through federal and state channels.
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Ocean Beach Renourishment, San Francisco, CA.

NCI was responsible for developing a suitable plan for placing up to 240,000 cubic yards of sandy material on Ocean Beach from the excavation for the Oceanside Water Pollution Control Plant. The plan was required as part of a California Coastal Commission permit to the City for work in this area. Services included preparing a plan that would minimize construction costs, improve the condition of the beach, and avoid bird nesting areas. The excavation material characteristics were analyzed to ensure that the material was suitable for beach placement. The plan was coordinated with and reviewed by the City, the California Coastal Commission, and the Golden Gate National Recreation Area. Inspections were performed during placement of the material. NCI also provided similar services to the City for placing 63,000 cubic yards of sandy material on Ocean Beach from material being excavated for the Lake Merced Transport Tunnel.

San Diego Regional Beach Sand Project, San Diego County, CA.

During the spring and summer of 2001, 2.1 million cubic yards of sand size sediments were dredged from six identified offshore borrow sites for nourishment of twelve selected receiver beach sites between Oceanside and Imperial Beach within San Diego County. This project, known as the San Diego Beach Sand Project, was the first regional beach restoration project undertaken on the West Coast of the United States. It was eight years in the planning, funding, engineering, permit processing and final design phases prior to the initiation of construction in early April 2001, with its completion in late September 2001. The Shoreline Preservation Committee of the San Diego Association of Governments (SANDAG), a joint powers organization, oversaw the planning and administration of this successful project that received funding from federal, state, and local government sources. Dredging and filling was performed by a trailing suction hopper dredge which utilized six ocean borrow sites and traveled to the individual twelve receiver beaches stretching between Oceanside and Imperial Beach. At the receiver beach, the dredge attached to a moored floating section of plastic/rubber pipeline that was attached to a submerged steel pipeline extending from approximately the -25 ft. MLLW depth contour to the shoreline. The six offshore borrow sites were dispersed from near the Mexico border to the north San Diego County line, and were located roughly one mile offshore in 45 to 90 feet of water depth.

NCI prepared all the final design and preparation of construction plans, specifications and contract documents for the dredging of sands from the six offshore borrow sites and the pumping of this sand to the twelve receiver beach sites. The project's design and contract documents allowed for the 2,100,000 cubic yards of dredging to be performed by using either cutter suction dredge and/or hopper dredge equipment. NCI's work also included overseeing construction bidding, award of contract, full-time construction management and inspection, and all hydrographic, aerial, and land side surveying for design and for construction. NCI also performed additionally required offshore marine geophysical survey work and offshore vibracoring/sediment analysis work at the offshore borrow sites.

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Upper Newport Bay Sediment Control Dredging, Newport Beach, CA.

NCI supported the County of Orange's Construction Division in overseeing the construction contractor's dredging of approximately 1,000,000 cubic yards of material with the Upper Newport Bay and its Unit III sediment basin. Services consisted of providing three construction inspectors, to oversee the contractor's dredging operation, and it providing construction oversight as requested to support the County's construction management staff. The contractor used both clam shell and cutter suction dredges over a 16 month period to place dredged material within dump scows (barges) which were then transported by ocean going tug boats to an EPA approved ocean disposal site approximately four miles offshore the entrance to Newport Harbor. In addition, services have been provided to the County in support of other dredge projects.


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Naval Air Station, North Island, Coronado, CA.

This project included dredging at Pier Bravo and the Quaywall turning basin at North Island, Coronado. NCI performed hydrographic and underwater obstruction surveys; vibracoring; geotechnical analyses; and prepared plans, specifications, bid documents and cost estimates for maintenance dredging of Pier Bravo and the quaywall turning basin area. Services included performing dredge material quantity computations and survey mapping using CADD and Siteworks software; preparation of specifications using SPECSINTACT; and development of detailed cost estimates.

Sunset Harbor/Huntington Harbour, Huntington Beach, CA.

NCI was responsible for all phases of the maintenance dredging project at Sunset Harbor/Huntington Harbour, involving 120,000 cubic yards in a 2-mile channel. Services included a project report to be used for planning, environmental documentation and permit processing; sediment sampling; sediment chemistry and bioassay laboratory analysis for ocean disposal; eelgrass survey; preparation of permit applications and an eelgrass mitigation plan; coordination with regulatory agencies; channel design; dredged material quantity computations; preparation of plans, specifications and engineer's cost estimate; construction support services; and two years of monitoring of the eelgrass transplant in accordance with the mitigation plan. Design criteria and channel layout had to be developed since dredging had not been performed for many years. The mitigation plan involved aquatically placing acceptable dredged material to create a suitable transplant site, and then transplanting the eelgrass. After two years of monitoring, it was determined that the eelgrass transplant was a success.
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Mandalay Canal Maintenance Dredging, Oxnard, CA.

This project involved the planning, design and permitting for the maintenance dredging of a power plant cooling water canal. Work involved hydrographic surveying, channel design, chemical analysis of sediments, preparation of permits and regulatory documents, evaluation of alternative upland dredged disposal sites, and preparation of plans and specifications for construction bidding. Noble Consultants, Inc. completed a pre- and post- dredge survey of the 11,000-foot long cooling water intake canal for the Mandalay Generating Station. The survey consisted of transverse sections across the canal at approximately 40-foot intervals along the entire length of the canal. The sections were acquired using our Trainable Acoustic Beam Sea Floor Profiler mounted on one of our survey vessels. On several occasions NCI surveyors assisted the dredge contractor in determining placement of his equipment along the winding canal. NCI surveyors conducted several interim surveys during dredging to determine compliance with the dredge plan. The data were processed and mapped using MicroStation software. Dredgeable material quantities were calculated, and electronic files of the maps were provided to the client.

Maintenance Dredging of Semeniuk Slough, Newport Beach, CA.

NCI performed a study to assess the feasibility of dredging the Semeniuk Slough. The tidal channel is an urbanized waterway that discharges directly into the Lower Santa Ana River wetlands. The scope of NCI's services included field surveying, sediment characterization, preliminary engineering, and strategic planning tasks. Technical analysis was directed to quantify the limits of dredging work necessary to restore the channel and determine the most economically feasible method to dispose of the accumulated sediment. A key component of the study was providing the City with recommendations on how best to implement and fund a project. NCI analyzed possible avenues of inter-agency coordination that might be available to the City to expedite the project and reduce the financial burden of dredging and future maintenance. NCI is currently assisting the City to move forward with a preferred dredging plan that incorporates innovative eco-system restoration measures and provisions for long-term maintenance.

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San Joaquin Marsh Enhancement, Phases I and II, Irvine, CA.

San Joaquin Marsh is a fresh water marsh that is managed as part of the University of California Natural Reserve System. The purpose of the Phase I Enhancement was to provide a reliable water source to a series of managed ponds to promote native marsh habitat. Noble Consultants was responsible for the planning; permitting; investigation; surveying; design; cost estimation; and preparation of plans, specifications, and contract documents for improving approximately 40 acres of historic wetland. Design services included civil, electrical and mechanical engineering, and landscape architecture. Construction oversight was also provided. The California State Coastal Conservancy funded this work. The project components included removing invasive plant species; grading twelve ponds to provide a setting for a range of native plant species; improving existing internal levees; constructing a pump station and a pipeline system to provide water to all of the ponds; installing water control structures; and planting native species.

Phase 2 of the San Joaquin Marsh Enhancement Project involved recreating the historic hydrology of the marsh by improving the infrastructure for routing and delivering water throughout the area adjacent to the managed ponds that were enhanced in Phase I. Noble Consultants was the prime consultant responsible for the project, under contract with the University of California, Irvine for Phase II while for Phase I work Noble Consultants was under contract to the California State Coastal Conservancy. Work for this phase involved surveying, planning, permitting, design, and preparation of contract documents. The design services included civil, electrical, and mechanical engineering, and wetlands design. Project components included excavation to provide channelization for water distribution; excavation to create a muted fresh water marsh connection to the creek; construction of a pipeline through a flood control levee; construction of a pipeline from an existing well to supplement creek water; and improving existing levees.

Yosemite Canal Wetlands Restoration, San Francisco, CA.

The Yosemite Canal Wetlands Restoration is currently an on-going project. Yosemite Canal is part of the Candlestick Point State Park Recreational Area. The purpose of the project is to expand wetlands in the area, provide public access, and improve wildlife habitats. A previous phase of the project involved developing alternatives, estimating construction costs, and preparing a feasibility report. NCI is responsible for hydrodynamic analysis, surveying, preparing grading plans, designing public paths, preparing construction cost estimates, and preparing contract documents.

Our design will consider, and dispose of as necessary, contaminated sediments in the area. The modeling study was part of the wetland restoration project and includes both the hydrodynamic simulation and sediment transport simulation for the Yosemite Canal and South Basin. The RMA2 model within the Surfacewater Modeling System (SMS) was used for the hydrodynamic simulation and the SED2D model was applied for the sediment transport simulation.

Pre-Dredge Survey Under Drydock Arco at the U.S. Navy Submarine Base, San Diego, CA.

NCI conducted a pre-dredge hydrographic survey under the Floating Drydock Arco, while the drydock was in place in light ballast. The survey was conducted using a Reson 9001 Multi-beam Hydrographic Surveying System mounted on NCI's survey vessel Western Warrior. The purpose of the survey was to determine the amount of siltation accretion, which had occurred since the area was originally dredged for the placement of Drydock Arco. Used a Reson 9001 Multi-Beam Hydrographic Surveying System mounted on NCI's survey vessel L'il Warrior to perform a hydrographic survey under the Navy's Floating Drydock Arco. In addition to the Reson 9001, we also utilized our IT 448 single beam depth sounder. Horizontal Position of the survey vessel, and steering information for the boat operator were provided by NCI's differential GPS navigation system. The data was processed and presented in maps generated in AutoCAD. Dredgeable material calculations were performed. Electronic files of each map were also provided to the client.

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Eel River Bathymetric Survey, Humboldt County, CA.

Noble Consultants was hired as a subcontractor to Towill, Inc. on this project to provide a bathymetric survey of the mouth of the Eel River and the confluence of the Salt River.  NCI’s effort was part of an overall topographic mapping along the Eel River for the U.S. Army Corps of Engineers.  Single-beam bathymetric soundings were collected and a bathymetric chart was prepared with sounding and contours.

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