To safeguard recreational users and nearby communities, the United States Forest Service (USFS) contracted RESPEC, an engineering consulting firm, to develop a comprehensive early-warning monitoring system. The system was designed to track both deep subsurface movement and shallow surface changes, providing real-time data for early detection and informed decision-making.
Solutions
Landslides pose a significant threat to public safety, property, and infrastructure. Recent high-profile landslides in the United States, including those in Oso, Washington, and Salt Creek, Colorado, have highlighted the need for effective monitoring and early-warning systems. Proactive detection allows authorities to protect communities and recreational areas before disaster strikes.
The integrated landslide monitoring framework combines deep borehole instruments, surface sensors, and wireless data transmission to provide a comprehensive and reliable early-warning system. By continuously measuring subsurface movement, surface displacement, and environmental factors such as rainfall and soil saturation, the system enables early detection of potential landslide activity and real-time assessment of slope stability. Data-driven alerts allow emergency responders and land managers to take timely action, reducing risk to visitors, downstream communities, and critical infrastructure.
In addition to immediate hazard detection, the system supports long-term monitoring, allowing researchers and engineers to analyze trends, evaluate slope behavior over time, and improve predictive models. With secure data transmission and centralized access, stakeholders can monitor conditions remotely, make informed decisions quickly, and maintain a higher level of preparedness in regions prone to landslides.
About 20 years ago, rainfall triggered a major landslide near Cook Lake in Wyoming, causing soil saturation in the Jurassic Sundance and Redwater mudstone formations. Key impacts included:
27-acre rotational landslide with a 15-meter head scarp
Evacuation and closure of a 19-unit campground and hiking trail
Threat to the dam, risking downstream flooding
The slide remains active today, with visible cracks, rockfall, and fluctuating water levels.
In 2016, RESPEC installed two deep boreholes to investigate the landslide’s failure plane. These boreholes were equipped with:
Downhole piezometers to monitor pore-water pressure
Time-Domain Reflectometry (TDR) cables to detect subsurface deformation
Inclinometers for precise measurement of ground movement
All sensors were integrated with Campbell CR6 dataloggers, ensuring continuous, high-resolution data collection of critical subsurface conditions.
Data from the boreholes is transmitted to a base station located approximately one mile from the site, using:
CR300-RF407 dataloggers with long-range radio capability
Satellite receivers for redundancy and remote access
This wireless network allows for real-time monitoring, even in remote areas, reducing the need for constant on-site observation.
To detect shallow ground movement and track precipitation, additional instruments were installed around the landslide perimeter:
Tiltmeters for surface displacement monitoring
Rain gauges to measure local rainfall and soil saturation
Each tiltmeter is connected to a CR300-RF407 datalogger, transmitting data back to the base station for continuous analysis.