California's horizontal drain applications span the state's landslide-prone coastal and mountain slopes, where Caltrans and hillside communities rely on drainage as a primary defense against the seasonal atmospheric river events that trigger the majority of the state's slope failures.
GSI treats this as one of several Steep Slope Stability Issues issues the state's infrastructure owners regularly face.
Horizontal drains bored into California's hillside slopes intercept groundwater before atmospheric river events can pressurize failure surfaces, addressing the state's primary landslide trigger directly. This draws directly on GSI's horizontal drains work.
Reducing pore water pressure through horizontal drains raises the factor of safety on California slopes at a fraction of the cost of structural reinforcement alone. GSI's soil nailing capability supports this step.
GSI pairs horizontal drains with soil nailing on California slopes where atmospheric river-driven saturation is severe enough that drainage alone cannot fully resolve an active failure. This is one application of GSI's broader landslide emergency response expertise.
GSI often considers engineers alongside this work when scoping California projects.
Engineered for California's conditions. GSI treats horizontal drains as California's primary defense against atmospheric river-triggered slope failure — the state's dominant landslide mechanism. GSI's general contractors and our case studies experience backs this approach.
Design/build delivery. Engineering and field crews work as one team — closing the communication gaps that separate design from construction.
Caltrans specification compliance. Documentation and installation methods align with DOT standards from the initial submission.
GSI's engineers are ready to assess horizontal drains conditions at your California site.
