Flood Mitigation Raised Foundations

FLI provides raised platforms and deep screw-pile flood protection foundations that safeguard substations, REBs, telecoms cabinets and other infrastructure from flood water.

Talk about low-cost flood alleviation.

"If there is no other option other than to build the substation in a flood risk area then the most effective way of protecting critical plant and equipment is to elevate it above the level of the flood."

UK Power Networks - Engineering Design Standard EDS 07 0106 4.1 - Substation Flood Protection

Substation flood protection with raised screw pile foundation

Why Raised Installations Are More Reliable Than Barriers, walls or bunds.

FLI’s elevated platforms provide a reliable alternative to flood barriers. If you need to protect an asset from, for example, a 1m depth of flood water, you can either surround it with a 1m high barrier or raise it 1m above the ground.

Barriers, whether permanent or temporary, have many potential points of failure. Foundations can be subject to water uplift or scour. Barriers have seals which can fail and gates that can be left open. Drains on site need non-return valves, which can fail. If the ground is soft then groundwater can rise but hard surfaces prevent water from draining away. A permanent barrier around a site has often been considered as the best retrofit solution but if any single element fails then the whole installation fails. Also if the barrier is overtopped by as little as 1mm then the whole site floods and all assets are impacted to the full depth of the flood.
In contrast, when an asset is raised above the ground on a deep foundation (that is not subject to water uplift or scour), then it cannot flood. And should the flood level excede the planned for height, the asset will only flood to the depth that the water has exceeded that height (1mm instead of 1m and 1mm).

Screw Piles for installations at risk of flooding.

Screw piles are a deep foundation solution, which takes their load bearing surfaces well beyond the effects of floodwater. They perform particularly well in the soft ground conditions often found in the alluvial soils of high risk flood plains. Unlike driven piles, installation causes no vibration and can be carried out with small plant right next to existing infrastructure. Indeed new structures can be built bridging existing buried services and legacy concrete foundations, enabling more efficient upgrading of sites.

Find out about screw piles

Blog Post:
Flood Mitigation Resilient Foundations

Applications in Energy, Rail, Water and Telecoms.

FLI engineer, manufacture and install staging mounted on screw pile foundations in rail, highways, telecoms, aviation and energy markets. FLI has delivered solutions for thousands of sites across the country, putting new structures into telecoms sites without disturbing existing towers, supplying overhead electrification steelwork into rail programmes and building platforms for Hinkley Point C.

Cabinets and staging raised above flood risk on FLI screw piles

Cost-Effective Flood Protection

Avoids the need for high cost and vulnerable whole site barriers.
Suitable for both new sites and upgrading existing sites. With site upgrades, the screw piles for staging can be installed without removing existing services or foundations and there is no concrete, so no delay waiting for concrete to set and cure.

As screw piles work in tension as well as compression, they are also ideal for structures like pylons and gantries that have high overturning moments.

Transmission Pylons

Cantilever Gantries

REB flood protection with screw pile foundation

REB Grillage & Pile Foundations

Cable management is integrated into the frame to simplify installation and allow good access to the cabling from the top of the platform.
If using raised sealed conduits across the site, these can be set into and accessed from the top of the platform.

REB platforms

GSM-r

FLI worked on over 2500 sites for Network Rail's telecommunications network (GSM-r). Many of these sites used our rapid deployment steel grillage and screw pile foundations for their cabins (REBs) and towers.

Rail Telecoms

Non Conductive Railing and Flooring

Developed initially for the Rail Network for some installations in close proximity to overhead power lines for trains.
The foundation and frame are steel (the more cost effective option), with the touchpoints of flooring and railing, being Fibre Reinforced Resin.
Again, with these products, the cabling is carried through the frame itself and can be accessed from above the platform.

LOC Platforms

Staging platform raised on screw pile foundation on embankment

Blog Post:
Flood Mitigation with Resilient Foundations: Protecting Against Flooding.