geotechnical projects
Skip Navigation Links | Willdan Engineering | Geotechnical Projects

Willdan has provided geotechnical engineering services on major bridge, airport, transportation, industrial, water/wastewater and essential institutions projects, as well as third party reviews. Listed below are sample projects.

Click the "plus" or category heading for project detail.

Open All Close All

kanan interchange

City of Agoura Hills, California
Kanan Road/101 Interchange Design

For this award-winning traffic mitigation project, Willdan performed geotechnical investigation that included development of drilling work plans, permit acquisition, traffic control, soil and rock logging, sampling, laboratory geotechnical tests, and foundation recommendations for highway improvements consisting of removal of existing off-ramps, relocation and widening of streets, construction of bridges and relocation and construction of new on- and off-ramps.

U.S. Army Corps of Engineers
Los Angeles River Bridge Repair & Replacement

Willdan provided an engineering geology and geotechnical engineering study for the replacement of a 755-foot railroad bridge over the L.A. River and a 282-foot bridge over the Dominguez Channel. The geotechnical investigation included drilling work plans, drilling safety plans, temporary diversion dikes in the river channel, soil logging, soil sampling, borehole abandonment, evaluation of nearby active faults, borehole geotechnical and geophysical testing, probabilistic seismic hazard analyses, quantitative liquefaction and settlement estimates, detailed pile design recommendations, borehole geophysical test report and foundation report.

This project was awarded the National APWA Project of the Year in the category of Disaster or Emergency Construction/Repair More than $10 Million.

Streets and Highways
alta canyada road distress

City of La Cañada Flintridge, California
Alta Canyada Road Distress

Willdan performed geotechnical investigation of Alta Canyada Road due to adjacent slope failure, including geologic mapping of slopes below road surface, drilling, soil sampling, preparation of a geologic cross section, computerized slope stability analyses to determine the deep-seated factor of safety of the road surface and recommendations for stabilization.

Los Angeles County Metropolitan Transportation Authority
Metro Orange Line Extension, Los Angeles

Provide all geotechnical engineering investigation and design to the design-build team for design and construction of four miles of dedicated busway, three stations, park and ride facilities, two bridge replacements over LACDPW flood control facilities, 3,000 linear feet of up to 40-foot-high MSE walls, and a 2,000-foot-long privacy/sound wall (which involved a site-specific subsurface investigation, feasibility evaluation of different Caltrans sound wall standard footings as well as custom footings, grading issues and final design selection).


Southern California Logistics Airport
Runway and Taxiway Improvements

Willdan performed geotechnical investigation in accordance with FAA regulations for the 2,000-foot extension of Runway 17/35 and for new pavement design and rehabilitation of Taxiway Bravo, designed to accommodate Airplane Design Group V aircraft (Boeing 747-400) with a design takeoff weight of 870,000lb. The fieldwork required drilling, sampling and geologic logging of thirty-two 18-inch diameter bucket auger borings to evaluate subsurface conditions. Report included CBR design values and pavement design recommendations, laboratory test results and engineering analyses.

Water / Wastewater Projects
la canada flintridge sewer

Morongo Band of Mission Indians
Above Ground Water Tank

The proposed above ground water tank for a new casino was located within a State of California Alquist-Priolo Fault Zone and County of Riverside Fault Hazard Zone for the San Gorgonio Pass Fault. The investigation involved a 300-foot, 11-foot deep trench to identify potential faults. Recommendations were made about mitigation strategies as required. Seismic hazard analysis included development of a site-specific response spectra for the eastern terminus of San Bernardino Mountain segment of the San Andreas fault which is located less than ½ mile from the site. Recommendations for mitigating the potential for settlement up to 4 inches induced by the strong ground motion were provided in the report.

City of La Cañada Flintridge, California
New Sanitary Sewer System

Willdan performed geotechnical investigation services and construction monitoring for 89,000 lineal feet of new sanitary sewer system to replace septic tanks. The investigation consisted of 70 exploratory borings, soil sampling and logging, geotechnical laboratory testing, engineering analyses, recommendations for trench shoring, and bedding and backfill requirements. Our field representative was onsite performing observation and testing during installation of the sewer pipes.

Review Services

Willdan has provided review services to dozens of clients, including:

  • Cal State University Sacramento
  • CSU Sacramento
  • California Energy Commission
  • Energy Facility
  • Calpine Corporation