Engineering Disciplines


Services

Wetlands & Lake Restorations

Laguna Niguel Lake Refurbishment, Laguna Niguel, CA.

NCI provided the engineering services for removing 200,000 cubic yards of accumulated material from a 40-acre lake and constructing miscellaneous lake improvements. Engineering services included planning; permit preparation and processing; sampling and testing; design; preparation of plans, specifications and cost estimates; quantity computations; alternative disposal site analysis; and construction services. Due to budgeting constraints, the project was to be phased over a five-year period. As a result of planning, the optimum project involved draining the lake; removing 100,000 cubic yards of material by processing it and reusing it to create an in-lake, 4-acre dredged material disposal site, to improve lake perimeter roads, and to reconstruct a wildlife island; landscaping; and, aquatic vegetation planting to improve water quality. The engineering included design of the disposal area perimeter dike and decant weir, and specifications for future dredging of the remaining material with placement in the disposal area. Additional funding became available during construction that allowed removal of all accumulated material. Excess material was placed in the disposal area. Subsequently, NCI prepared plans and specifications for removing the stockpile and disposal site perimeter dike material, and using it on a County road project.
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Hansen Dam 15-Acre Recreational Lake, Los Angeles, CA.

The Corps of Engineers was directed to plan, design and construct a recreational lake and associated recreational facilities at Hansen Dam. To initiate the planning and design process, NCI prepared the Feature Design Memorandum that presented all engineering design criteria for final design and construction of a 2-acre swimming area for swimming, sunbathing and child's wading activities; a 13-acre recreational water area for non-powered boating, sailing and fishing uses; and associated recreational facilities for parking, turf/picnic areas, restrooms, lifeguard buildings and stands, launching ramp, footpath and service road. This included engineering criteria for all civil design, hydraulic design, landscape design, and design of associated recreational facilities. Design elements consisted of the lake's physical layout; lake liner and shoreline treatments; drainage features; and water quality control for the swimming area, filtration pond and recreational area. Water quality control consisted of chlorination, circulation/filtration, aeration and ozonation systems. A comprehensive construction cost estimate and operations/maintenance cost estimates were developed for this project using the Corps' M-CACES program.

Laguna Coast Wilderness Park-Laguna Lakes Restoration, Laguna Beach, CA.

NCI was responsible for the design, preparation of plans and specifications, and construction monitoring for the restoration of three lakes and adjacent foliage in the Laguna Canyon Greenbelt area. The purpose of the project was to improve water quality in the lake, eliminate flood related influx of upland sediment, and encourage the growth of native plant species. The components of the project included removal of accumulated sediment, construction of a sedimentation basin and overflow structure, removal of sediment from a box culvert between two of the lakes, construction of berms to encourage wetland plant growth in upland areas, removal of eucalyptus trees and other exotic plants, and planting of native species. The project was completed prior to the heavy rains in 1998. The sediment basin functioned as designed to eliminate influx of unwanted sediment into the lakes.

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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.

Scottsdale Pond Park Improvement, Novato, CA.

Scottsdale Pond is a 10-acre pond located in the City of Novato that is a flood control and recreational park facility. It is a non-contact water area that is used by birds and enjoyed by the public. The purpose of this improvement was to improve water quality to the pond, construct an island, improve the aesthetics around the perimeter of the pond, and improve public access. Noble Consultants was the prime consultant responsible for the surveying, investigations, planning, permitting, design and preparation of contract documents for the project. Design services involved civil, electrical, and mechanical engineering, and landscape architecture. Project components included excavation of the pond; construction of an island; installation of aerators; contour of upland area to provide scenic berms; provide ADA access; planting around the pond and on the island; improve aesthetics of existing hardscape features; and provide mitigation for reduction of flood storage capacity.

Three alternatives were developed during the planning phase that varied the size and shape of the island, the quantity of material to be excavated from the pond and landside improvements. Variations in the size and shape of the island were proposed to alter the potential impacts on flood flows around the island and to alter the variety of plants that could be used. Also, the island layout and pond bank excavation were designed to minimize the chance for invasive plants to grow.

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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.

Bolsa Chica Wetlands Restoration EIS/EIR, Bolsa Chica, CA.

The Bolsa Chica project area consists of 1,247 acres of the Bolsa Chica Lowlands in the Bolsa Gap between Bolsa Chica Mesa on the northwest and Huntington Mesa on the southeast in an unincorporated area of northwestern Orange County. The purpose of this project was to restore wetland and aquatic functions at Bolsa Chica as oil extraction is phased out and after contamination is removed. The EIR/EIS was prepared for the California State Lands Commission, the U.S. Fish & Wildlife Service and the U.S. Army Corps of Engineers.

Phase I consisted of 366.5 acres and includes buying out and deactivating the oil wells within the project site; dredging approximately 2.7 million cubic yards of sediments to create a tidal basin; constructing an ocean inlet into the basin for 619.5 acres after the remaining oil operations are decommissioned and the existing wells, pipelines and oil-related contaminants are removed.

NCI prepared a detailed coastal and estuarine engineering assessment for the EIR/EIS of the proposed Bolsa Chica Wetlands Restoration Project. This project entailed the redefinition of the area's hydrodynamic and shoreline processes regime resulting from the proposed Bolsa Chica tidal inlet. NCI reviewed the preliminary modeling results and provided valuable comments and suggestions to finalize the hydrodynamic modeling results. The tidal inlet was designed to improve the exchange of ocean water to and from the wetlands area. Baseline coastal conditions at the site were established and compared to the potential impacts of the proposed project. A series of alternatives were assessed to determine their respective oceanographic significance with respect to wave heights and currents, beach loss, increased shoaling of sensitive areas, and the disruption to the littoral transport regime. Mitigation measures to address and minimize potential adverse coastal impacts were analyzed as well.

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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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Hamilton Wetland Restoration Project; N-2 Levee & South Levee Design, Novato, CA.

Noble Consultants was hired as the prime consultant to perform design services and prepare contract documents for construction of two perimeter levees related to the Hamilton Wetland Restoration project located in San Francisco Bay, California.  The restoration project involves converting a decommissioned army airfield by constructing perimeter levees and internal berms and hydraulically placing dredged material to create appropriate topography for seasonal and intertidal wetlands.  Thirteen levees/berms have been constructed.  NCI has prepared the design on eleven of these structures.  The current project involves the 4,750 foot long N-2 Levee and the 2,980 foot long South Levee.  Preliminary design was performed and design criteria provided by the Corps.  NCI prepared the detailed design layout, designed the crossing over a 54-inch diameter pressurized sewer outfall, designed the surface course for the N-2 Levee, and provided recommendations on the feasibility for using recycled concrete in lieu of aggregate base for the N-2 surface course.

The work conducted and deliverables submitted include final design, preparation of plans and specifications, preparation of an MCACES (MII) cost estimate, preparation of a Storm Water Pollution and Prevention Plan (SWPPP), and response to questions using Dr. Checks.  Independent Technical Review (ITR) was provided through a subcontract to NCI.  Construction engineering services will be provided during construction.

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