When extreme weather events occur, communities are often left to grapple with the devastating effects. An increase in extreme weather patterns, coupled with aging or inadequate infrastructure, amplifies the often dangerous and costly damage that ensues—especially for vulnerable communities living in low-lying areas.
According to a recent study, the United States could see a 26.4% increase in flood risk by 2050, which could cause significant damage to existing infrastructure. For this reason, it is vital to build resilience into infrastructure projects to mitigate climate risk and ensure the long-term reliability of critical infrastructure.
Incorporating geosynthetics into infrastructure can improve the ability of communities to withstand and recover from extreme weather events. For example, in hurricane-prone parts of the country, designing robust access roads along power transmission lines allows repair crews to safely and quickly restore power to communities that might otherwise be without electricity for days or even weeks. Geosynthetic products, such as geocells, can be used to construct reliable access roads along transmission infrastructure, which often traverse very remote areas with difficult terrain and very soft ground conditions. Through an interconnected honeycomb-like network, geocells confine and stabilize soils that would otherwise be unstable under loading.
When used in load support, slope stabilization, channel protection, and retaining wall applications, geocells are a powerful weapon against the long-term effects of climate change. This article discusses several examples where GEOWEB® geocells were successfully used to help communities adapt to, and recover from, extreme weather events.
GEOWEB porous pavements used for rebuilding roads, replacing transmission lines damaged during Hurricane Michael in Florida’s panhandle
Hurricane Michael caused extensive damage to Florida’s power grid network, leveling more than 100 transmission towers in a 34-mile right-of-way from Port St. Joe to Callaway. This right-of-way crosses swampy, remote, and hard-to-reach areas, making rebuilding the grid even more challenging. This extremely wet, muddy ground prevented repair vehicles from accessing the area. Helicopters were employed to transport the new steel towers installed on-site.
Accessing the lines for maintenance would require a stronger roadway to support heavy vehicles in the wettest areas. The GEOWEB Load Support System was used to make the roads operational and improve performance in saturated conditions.
The GEOWEB system was placed over an enhanced geotextile and filled with crushed aggregate to create access roads across critical wetlands and stabilize pole pads. The access roads and pads are permanent.
In the spring of 2018, several storms violently swept through areas along southern Maine’s coastline, devastating the beaches and trails of Fort Foster—a town-owned park in Maine. Known as “nor’easters,” these destructive storms form along the east coast, bringing strong winds, rain, and flooding to the New England states. As the storms rolled past, the damage was visible to Fort Foster and Kittery Point’s 2.1-mile-long shoreline walking trail and maintenance road, as well as on the slopes leading down to the beach.
The park’s goal was to repair the damage and protect the slopes, maintenance road, and recreational trail from future storm damage. The GEOWEB® Soil Stabilization System was chosen to restore and protect two sections of the park’s shorelines and trails.
By using the GEOWEB system, the park was able to armor the maintenance road, recreational trail, and slopes from future storm events. Since being installed in 2018, the GEOWEB load support and shoreline protection systems continue to perform as designed, allowing the community to once again enjoy the trail system and local beaches.
The extreme El Niño event caused the western Pacific to warm, developing atmospheric convection and increased rainfall. The storm events caused catastrophic flooding and severe erosion in the eastern equatorial region of Ecuador and Northern Peru. A portion of the Zarumilla River, located in the remote Tumbes region in Northwestern Peru, was experiencing severe erosion and required a shoreline protection solution to prevent further deterioration of the riverbank.
The GEOWEB® Shoreline Protection System was selected to protect the Zarumilla riverbank against future storm events. The GEOWEB system with concrete infill provides economical, hard-armored protection of slopes and channels exposed to high flow velocities and high shear stresses. The system has been proven to withstand sustained flow velocities over 36 ft/s (11 m/s) and shear stresses of 20.9 psf (1.0 kPa), outperforming rip-rap, gabions, and other conventional hard armor strategies.
The product was shipped to the site in September 2020, and installation was complete by December 2020. The project was completed on schedule and within budget. The GEOWEB® Shoreline Protection System is performing to expectations and will provide much-needed protection to the Zarumilla River and the communities that depend on it when the next major storm hits.
GEOWEB Geocells used for erosion protection of canal floodwall
Erosion of the 17th Street Canal’s flood protection system was a major concern for the Southwest Louisiana Flood Protection Authority-East. The authority required a solution to protect the canal’s slope against erosive forces and prevent a floodwall breach in the event of a tropical storm event.
To mitigate channel slope erosion, engineers chose the GEOWEB® Confinement System to stabilize the slopes along the Metairie side of the drainage channel. By confining the infill material, the GEOWEB system prevents flow from causing scour and erosion on slope surfaces.
The construction company installed approximately 380,000 square feet of GW40 (mid-cell size, six-inch deep panels) over a woven geotextile along the canal’s slope and infilled the cells with crushed aggregate sized based on research and testing at Colorado State University hydraulics lab.
The GEOWEB System:
Allows the use of smaller, less expensive rock—even waste rock which decreases installation and transportation costs.
Creates a permeable, cover when drainage is desired but vegetation cannot be established.
Resists high velocities and tractive forces.
The engineering team at Presto Geosystems works closely with engineers and project planners, offering free project evaluation services and on-site support. Its recommendations will deliver a technically sound, cost-effective solution based on four decades of accredited research and testing data.