Hazard protection solutions

The cost of natural hazards

Natural hazards, such as floods, wildfires, and hurricanes, have inflicted substantial economic losses worldwide. In 2022 alone, global flood-related damages amounted to over $82 billion, accounting for nearly a third of all losses from natural catastrophes that year. 

Over the past two decades, extreme weather events have cost the global economy an estimated $2.8 trillion, averaging around $143 billion annually.

These staggering figures underscore the urgent need for comprehensive strategies to prevent or mitigate damage. Public authorities must invest in resilient infrastructure and early warning systems, while the insurance industry faces increasing strain to cover escalating claims. Collaborative efforts among communities, governments, and private sectors are essential to develop and implement effective solutions, ensuring a safer and more resilient future for all.

Steel sheet piles can help prevent damage

Steel sheet piles, built as strong and reliable retaining structure, can help safeguard communities from natural disasters. By the end of this module you will be aware of the various applications and advantages of steel sheet piles in the protection against natural hazards.

Natural hazards

Flooding, erosion, storms, drought...

Natural hazards generate a very high cost in human lives and infrastructure damage (houses, businesses, public equipment). Steel sheet piles can be used to mitigate some of them. In the next sections we will see how sheet piles are used, with example case studies.

Flood protection barriers

As a flood wall, a sheet pile wall can simply replace a flood embankment, without any reduction in performance. This option is of particular interest in ports or other urban areas where space is limited. The protection can be extended to storm situations (serving as storm surge barriers).

Groynes

Groynes protect the beaches are rivers from erosion due to the wave and current actions. The presence of groynes allows for sedimentation which mitigates the erosion activity.

River embankments

With a sheet pile wall, not only can an embankment be made watertight, but it can also be modified to hold back a larger design flood without requiring a greater footprint. This can be achieved by designing the sheet pile wall to project the requisite height above the crest.

Dyke reinforcements

For stability, sheet pile walls can be designed to mechanically reinforce the dyke. Their flexibility is highly useful, as they accommodate potential soil displacement while maintaining full resistance.

Earth stabilization

For new embankments, steel sheet piles provide essential structural support by preventing soil displacement, reinforcing slopes, and controlling water infiltration. They act as a strong retaining barrier, resisting lateral earth pressures and ensuring the embankment remains stable even under heavy loads or varying soil conditions.

Watertightness

Steel sheet piles ensure proper watertightness, either by the presence of soil particles or sealants at the interlock, which is crucial to maintaining the long-term stability and performance of retaining walls.

Support

Steel sheet piles support weakened parts of an embankment (inner shoulder, outer shoulder,...) by increasing its strength.

Manalapan seawall - USA

The project is reconstruction of seawalls in Manalapan, Florida, following damage caused by Hurricane Sandy in 2012. The original seawalls, built in the 1960s, failed due to overtopping, exposing their support systems. 

Replacement involved using stronger, coated steel sheet piles with a longer design life, and incorporating improved designs to enhance stability. The project faced a tight timeframe due to environmental regulations protecting sea turtle nesting grounds. The successful completion involved multiple contractors and significant quantities of steel sheet piling.

Read the full case study

Huntington beach river rehabilitation - California - USA

For this river channel rehabilitation project in Huntington Beach, sheet pile construction was used to keep heavy construction equipment out of the channel. This method eliminated the need for widespread dewatering. The sheet piles could be driven year-round, even in winter, as all the equipment remained outside the channel’s flood conveyance. 

Installation was carried out using low-noise pressing equipment. Initially, a concrete solution was considered, but due to high seismic activity and noise level restrictions, sheet piles were ultimately chosen.

Flood defence barrier in Boston - UK

Following severe flooding, a £100 million project using steel sheet piling was undertaken to protect over 14,000 properties. The complex design involved a multi-functional barrier incorporating a gate, fish pass, and flood walls, necessitating the use of various steel pile types from ArcelorMittal. Construction challenges, including hard ground conditions, were overcome using specialist equipment and techniques. The project, completed in 2019, significantly enhances flood protection for the town of Boston.

Read the full case study