In September 2017 Hurricane María triggered more than 70,000 landslides across Puerto Rico that caused loss of life and widespread damage to transportation, communication, and power-supply infrastructure, and to other public and private property.
Reduction of Hazards from Intense Rainfall-Induced Landslides in Puerto Rico
To help to reduce the hazards from future landslide events, the USGS Landslide Hazards Project (LHP) and their partners are performing a 3.5-year-long study that will improve understanding of landslides in Puerto Rico and methods for spatially and temporally forecasting landslide occurrence. More specifically, the LHP is leveraging advances in remote sensing (primarily lidar, InSAR, and optical imagery), laboratory testing, and field observation, monitoring, testing, and data collection to map, characterize, and analyze landslides throughout Puerto Rico. These studies will improve understanding of where and when landslides are most likely, which is of critical importance, but also the characteristics of landslides as they form and move downslope; most landslides in Puerto Rico display long travel distances making them hazardous far from their initiation sites. Led by partners at the University of Puerto Rico – Mayagüez, the USGS has published an inventory of landslides triggered by Hurricane Maria and an island-wide map depicting susceptibility to intense rainfall-induced landslides that was developed using the inventory and analyses of multiple factors contributing to landslide occurrence. The LHP also continues development of state-of-the-science tools for modeling and forecasting where landslides are likely to occur, and where they are likely to travel after occurrence. Models are being developed and tested using input obtained from our remote sensing, field, and laboratory studies. Following validation, models will be applied to create landslide susceptibility maps for areas having highest priority for landslide hazard reduction.
For More Information
- Other USGS science activities and research in Puerto Rico
- Puerto Rico Landslide Hazard Mitigation Project - Natural Hazards Center
- Puerto Rico Landslide Susceptibility Tool - English
- Puerto Rico Mapa De Susceptibilidad A Deslizamientos De Tierra Aplicación Web - Spanish
- SLIDES-PR: Storm-induced Landslide Impact Dynamics on Environment and Society in Puerto Rico (Hughes UPRM Geology)
- Have you thought about what would happen if your property were affected by a landslide? (Natural Hazards Center)
- ¿Has pensado qué pasaría si tu propiedad fuera afectada por un deslizamiento de tierra? (Natural Hazards Center)
Puerto Rico Landslide Hazard Mitigation Project
Below are FAQ associated with this project.
What is a landslide and what causes one?
A landslide is defined as the movement of a mass of rock, debris, or earth down a slope. Landslides are a type of "mass wasting," which denotes any down-slope movement of soil and rock under the direct influence of gravity. The term "landslide" encompasses five modes of slope movement: falls, topples, slides, spreads, and flows. These are further subdivided by the type of geologic material...
Can major landslides and debris flows happen in all areas of the U.S.?
Landslides can and do occur in every state and territory of the U.S.; however, the type, severity, and frequency of landslide activity varies from place to place, depending on the terrain, geology, and climate. Major storms have caused major or widespread landslides in Washington state, Oregon, California, Colorado, Idaho, Hawaii, Virginia, Ohio, Pennsylvania, Tennessee, North Carolina, Puerto...
What is the difference between a landslide advisory, a landslide watch, and a landslide warning?
An advisory is a general statement about the potential of landslide activity in a given region relative to developing rainfall predictions. An advisory may include general statements about rainfall conditions that can lead to debris-flow activity, and list precautions to be taken in the event of heavy rainfall. A watch means that landslide-activity will be possible, but is not imminent. People in...
What is a debris flow?
Debris flows are fast-moving landslides that are particularly dangerous to life and property because they move quickly, destroy objects in their paths, and often strike without warning. They occur in a wide variety of environments throughout the world, including all 50 states and U.S. Territories. Debris flows generally occur during periods of intense rainfall or rapid snowmelt and usually start...
What is a landslide hazard map?
Several kinds of maps are used to depict danger from landslides. These maps might be as simple as a map that uses the locations of old landslides to indicate potential instability, or as complex as a map incorporating probabilities based on variables such as rainfall, slope angle, soil type, and levels of earthquake shaking. The following types of maps are used to describe and depict landslide...
Do human activities cause landslides?
Yes, in some cases human activities can be a contributing factor in causing landslides. Many human-caused landslides can be avoided or mitigated. They are commonly a result of building roads and structures without adequate grading of slopes, poorly planned alteration of drainage patterns, and disturbing old landslides. Detailed on-site investigation is required to determine the importance of human...
Under what circumstances do U.S. Geological Survey landslide personnel conduct field work in landslide-prone areas?
USGS landslide researchers have ongoing field projects in several areas of the United States, including parts of the Pacific coastal ranges, Rocky Mountains, and the Appalachians. USGS scientists also respond to major landslide events, including some that result in federally-declared disasters. In some cases, USGS scientists respond to landslides in foreign countries that request assistance...
- Overview
In September 2017 Hurricane María triggered more than 70,000 landslides across Puerto Rico that caused loss of life and widespread damage to transportation, communication, and power-supply infrastructure, and to other public and private property.
Reduction of Hazards from Intense Rainfall-Induced Landslides in Puerto Rico
Sources/Usage: Public Domain.Landslide that filled a home and buried a road in Utuado, Puerto Rico. To help to reduce the hazards from future landslide events, the USGS Landslide Hazards Project (LHP) and their partners are performing a 3.5-year-long study that will improve understanding of landslides in Puerto Rico and methods for spatially and temporally forecasting landslide occurrence. More specifically, the LHP is leveraging advances in remote sensing (primarily lidar, InSAR, and optical imagery), laboratory testing, and field observation, monitoring, testing, and data collection to map, characterize, and analyze landslides throughout Puerto Rico. These studies will improve understanding of where and when landslides are most likely, which is of critical importance, but also the characteristics of landslides as they form and move downslope; most landslides in Puerto Rico display long travel distances making them hazardous far from their initiation sites. Led by partners at the University of Puerto Rico – Mayagüez, the USGS has published an inventory of landslides triggered by Hurricane Maria and an island-wide map depicting susceptibility to intense rainfall-induced landslides that was developed using the inventory and analyses of multiple factors contributing to landslide occurrence. The LHP also continues development of state-of-the-science tools for modeling and forecasting where landslides are likely to occur, and where they are likely to travel after occurrence. Models are being developed and tested using input obtained from our remote sensing, field, and laboratory studies. Following validation, models will be applied to create landslide susceptibility maps for areas having highest priority for landslide hazard reduction.
Sources/Usage: Public Domain.Rockslide that blocked a road into the El Yunque National Forest, Puerto Rico. For More Information
- Other USGS science activities and research in Puerto Rico
- Puerto Rico Landslide Hazard Mitigation Project - Natural Hazards Center
- Puerto Rico Landslide Susceptibility Tool - English
- Puerto Rico Mapa De Susceptibilidad A Deslizamientos De Tierra Aplicación Web - Spanish
- SLIDES-PR: Storm-induced Landslide Impact Dynamics on Environment and Society in Puerto Rico (Hughes UPRM Geology)
- Have you thought about what would happen if your property were affected by a landslide? (Natural Hazards Center)
- ¿Has pensado qué pasaría si tu propiedad fuera afectada por un deslizamiento de tierra? (Natural Hazards Center)
- Science
Puerto Rico Landslide Hazard Mitigation Project
The USGS Landslide Hazards Program and the Natural Hazards Center have partnered with the University of Puerto Rico Mayagüez Geology Department to develop outreach materials on landslide hazards and shared resources and interdisciplinary expertise with a broad range of counterparts in Puerto Rico. - Data
- Multimedia
- Publications
- News
- FAQ
Below are FAQ associated with this project.
What is a landslide and what causes one?
A landslide is defined as the movement of a mass of rock, debris, or earth down a slope. Landslides are a type of "mass wasting," which denotes any down-slope movement of soil and rock under the direct influence of gravity. The term "landslide" encompasses five modes of slope movement: falls, topples, slides, spreads, and flows. These are further subdivided by the type of geologic material...
Can major landslides and debris flows happen in all areas of the U.S.?
Landslides can and do occur in every state and territory of the U.S.; however, the type, severity, and frequency of landslide activity varies from place to place, depending on the terrain, geology, and climate. Major storms have caused major or widespread landslides in Washington state, Oregon, California, Colorado, Idaho, Hawaii, Virginia, Ohio, Pennsylvania, Tennessee, North Carolina, Puerto...
What is the difference between a landslide advisory, a landslide watch, and a landslide warning?
An advisory is a general statement about the potential of landslide activity in a given region relative to developing rainfall predictions. An advisory may include general statements about rainfall conditions that can lead to debris-flow activity, and list precautions to be taken in the event of heavy rainfall. A watch means that landslide-activity will be possible, but is not imminent. People in...
What is a debris flow?
Debris flows are fast-moving landslides that are particularly dangerous to life and property because they move quickly, destroy objects in their paths, and often strike without warning. They occur in a wide variety of environments throughout the world, including all 50 states and U.S. Territories. Debris flows generally occur during periods of intense rainfall or rapid snowmelt and usually start...
What is a landslide hazard map?
Several kinds of maps are used to depict danger from landslides. These maps might be as simple as a map that uses the locations of old landslides to indicate potential instability, or as complex as a map incorporating probabilities based on variables such as rainfall, slope angle, soil type, and levels of earthquake shaking. The following types of maps are used to describe and depict landslide...
Do human activities cause landslides?
Yes, in some cases human activities can be a contributing factor in causing landslides. Many human-caused landslides can be avoided or mitigated. They are commonly a result of building roads and structures without adequate grading of slopes, poorly planned alteration of drainage patterns, and disturbing old landslides. Detailed on-site investigation is required to determine the importance of human...
Under what circumstances do U.S. Geological Survey landslide personnel conduct field work in landslide-prone areas?
USGS landslide researchers have ongoing field projects in several areas of the United States, including parts of the Pacific coastal ranges, Rocky Mountains, and the Appalachians. USGS scientists also respond to major landslide events, including some that result in federally-declared disasters. In some cases, USGS scientists respond to landslides in foreign countries that request assistance...