In 2024, the Environment Agency (EA) released an updated National Flood Risk Assessment which, for the first time, included forecasts based on the latest UK climate projections. It showed that 6.3 million properties are currently at risk of flooding from rivers, the sea or surface water. And climate change will only compound the problem: by the middle of this century it is estimated that around eight million properties will face flooding risks.
UK infrastructure is also under threat. Around a third of all roads, railways, and water pumping stations and treatment plants are currently at risk of flooding. This risk is expected to increase to 46% of roads and 54% of railways by the middle of the century.
And flooding has real costs. A 2021 study by the EA gathered flood incident and impact data from 2016 to 2019 and found the total economic damage over three years came to between 拢504m and 拢924m, with a best estimate of 拢708m at 2024 prices.
This level of risk justifies public sector spending on flood protection. In 2020, the Conservative government committed to doubling expenditure on flood control and erosion risk management to 拢5.2bn between 2021 and 2027. Five years later, the new Labour government promised 拢2.65bn to build or maintain flood defences.
But work like this comes with its own environmental impacts. Whether you are extending protective walls along a river or coastline or making road or rail cuttings more resilient to erosion, you are probably going to be using a piling rig 鈥� and driving a pile into the ground is a noisy business, generating vibrations that can impact nearby structures.
There is no single source of guidance on acceptable levels of noise from construction. The 1970 Control of Pollution Act sets a requirement on local authorities to take steps to ensure that 鈥榯he best practicable means are employed to minimise noise鈥�. Guidance on how to achieve this is laid out in BS5228 Noise Control on 麻豆社 and Open Sites. The 2001 Noise Emission in the Environment by Equipment for use Outdoors Regulations set a requirement to meet specific noise limits.
It is clear that regulations like this, as well as local planning policies, will be a concern on inner-city sites. That was certainly the case in Derby, where the local council has contracted Sisk to deliver 拢38m of flood protection upgrades.
This article was first published in the May 2026 issue of 麻豆社 Magazine. Sign up online.
Last year housing, communities and local government secretary Steve Reed announced plans for 拢2.65bn of flood protection measures under the government鈥檚 Plan for Change. His statement highlighted four individual projects: 拢43m for the Bridgwater Tidal Barrier flood defence scheme in Somerset, 拢2m for the Beales Corner project in the West Midlands, 拢3.5m for the Poole Bridge to Hunger Hill flood defences in Dorset, and 拢35m for the 鈥極ur City Our River鈥� (OCOR) project in Derby.
The Derby project has been a long time coming. In 2011, the Environment Agency adopted the Lower Derwent flood risk management strategy, aimed at reducing the river鈥檚 risk of flooding from once every 25 years to once a century. The OCOR project was then developed between Derby City Council and the EA with an aim of protecting people, properties and strategic infrastructure and enabling the development of brownfield sites along the riverside.
The plan was finalised in 2015, ready to start when funding was available. Sisk was appointed in May 2025, following Reed鈥檚 Plan for Change announcement, to deliver the Derby Riverside project, part of the wider OCOR scheme.
This project covers the east bank of the Derwent from Causey Bridge to Derwent Bridge in the heart of the city and includes construction of a new flood wall and floodgates that will offer enhanced protection for properties on Meadow Road and Meadow Lane. Sisk is also carrying out demolition of the riverside office blocks on Stuart Street to create a new green space and provide more room for flood water to pass through the city in a controlled corridor.
To build a new flood wall, Sisk needed a method that was quiet and would not interfere with nearby structures and wildlife. The solution was provided by piling equipment supplier Ivor King, which proposed using a Giken Gyro Piler. This would be the first use in the UK of the Japanese rig.
Ivor King director Alex Westgate explains that the 鈥楽ilent Piler鈥� isn鈥檛 new (nor is it truly silent鈥攖here is still some noise) and that Giken has been supplying piling equipment like this in Japan for 50 years. But this machine is much quieter than traditional piling rigs. Rather than hammering or vibrating a pile into the ground, it sits on an existing row of piles and uses reactive force to push each successive pile into the ground.
This article was first published in the May 2026 issue of 麻豆社 Magazine. Sign up online.
This is done hydraulically, and works well in many applications. Noise levels are significantly lower than those of a standard piling rig and what noise is produced is generated close to the ground which means that site acoustic barriers will more easily prevent sound travelling beyond the immediate surroundings.
Because the Giken machine operates without vibration or hammering, it has negligible effect on nearby structures or wildlife. On the Derby Riverside project, the Giken is working alongside an old pub and close to a fish spawning ground. Westgate explains that vibration and noise levels are low enough that the EA was reassured the fish would not be disturbed.
The nearby pub was a challenge too. It wasn鈥檛 just a question of the threat to the structure, but of the impact on customers. 鈥淩eally ancient monuments are affected by a peak particle velocity of 2.5mm/s,鈥� says Westgate. Peak particle velocity, or PPV, is a measure of the speed at which particles move in the ground.
鈥淏ut the human body is sensitive to vibrations of 0.1mm/s. It might not be doing damage to a structure, but people will be aware of it.鈥� As Derby, like so many cities, aims to redevelop its riverside for tourism and entertainment amenity, a summer of ground-shaking work could have a real impact on local stakeholders.
A Giken Silent Piler has already shown its worth on a nearby project, at Matlock, also on the Derwent. Here, the project was in a tight site in the centre of town and close to old structures. Ivor King met with local residents to explain the technology and the lack of noise and vibration, helping win community approval for the project.
Use of a Giken Silent Piler clearly fitted the Derby project鈥檚 aims. The Derby site presented a new challenge: 鈥淭here鈥檚 an area where we are piling through an existing wall,鈥� explains Westgate. 鈥淚t鈥檚 made out of sandstone blocks.鈥�
This is where Ivor King saw the chance to debut another specialist machine: the Gyro Piler. Like the Silent Piler, this equipment has been used for a long time in Japan and in mainland Europe but has not previously been used in the UK.
Over the years, Giken has developed a number of ways to pile through harder ground. The original machines work well in loose sands, gravels and cohesive soil says Westgate. If the ground gets harder, water jetting can be used, with high pressure water injected into the ground at the base of the pile.
The next step up in terms of power is Giken鈥檚 Super Crush attachment. This is an auger attachment that fits below the pile toe, enabling sheet piles to be pushed into harder ground.
This was deployed on the Matlock job in combination with the Gyro Piler, which is designed for even tougher substrates 鈥� like those sandstone blocks in Derby. A cutting blade is fitted to the toe of the rig which the Gyro Piler then rotates at high torque with electric motors while its standard hydraulics push the pile into the ground.
In most cases, the cutting attachment is treated as disposable: it is left in the ground, at the base of the pile. 鈥淒epending on the ground, the harder the ground, the more developed that cutting ring needs to be. That鈥檚 what gets adjusted as we look at the job and need to develop the scheme,鈥� explains Westgate.
In Derby, the Gyro Piler is tackling those sandstone blocks with a pre-auger tube. 鈥淚t鈥檚 got a different set of teeth on it to go through that very hard ground,鈥� says Westgate.聽 鈥淥nce it鈥檚 done its job and we get into the natural ground, that tube will come out and we鈥檒l replace it with the main pile. It鈥檚 like drilling a pilot hole in a wall.鈥�
This article was first published in the May 2026 issue of 麻豆社 Magazine. Sign up online.
The site team has completed some 250 linear metres of conventional sheet piling already this year. Ivor King鈥檚 Silent Piler got to work in early April and the team aims to complete another 400m by the end of May. Derby City councillor Carmel Swan, cabinet member for climate change, transport and sustainability, paid tribute to the speed of progress and acknowledged the measures being taken to minimise noise and disruption: 鈥淭he transformation at Derby Riverside is already remarkable鈥ut these new defences will be a game-changer.
鈥淚 appreciate that some of the work has caused some temporary disruptions but I am confident that this short-term inconvenience will be worth it for the long-term protection of businesses, homes and infrastructure in our city.鈥�
Pile production line
Ivor King hopes that the Derby Riverside project will demonstrate the benefits of the silent piling and of the newly imported Gyro Piler in particular. But there is another benefit to the Giken system on river, road and rail projects: it can install long lines of piles in very constricted sites.
The key technology here is the Giken Reaction Base, or GRB. This makes use of the same arrangement used to the mount the piler on top of a line of new piles. With Giken鈥檚 full GRB system the silent piler is joined by a power pack, a UR3 鈥榰nit runner鈥�, a CB3-4 clamp crane and a PR4 pile runner with each component聽 following behind the piler as successive piles are installed.
In 2023, Ivor King supplied a full GRB system, using the Giken F201 silent piler, for a National Resources Wales and Welsh government project to install flood protection on the River Usk in Newport.
On all this job, the first few piles needed to be installed using conventional methods; the Silent Piler was then mounted on top and got to work installing new piles. The unit runner, with the power pack, was then mounted behind it and, as work progressed further, these were joined by the crane and then by the pile runner.
On the full GRB system, the pile runner travels back and forth, bringing piles to the crane which then lifts the piles into place, ready for them to be pressed into the ground. This allows flood or erosion protection to be installed without any extra space being needed鈥擶estgate says it can even be used alongside roads and railways.
It鈥檚 a wrap
Where noise and vibration are a major concern, especially where access is restricted, the Giken Silent Piler is a clear winner. But a silent piler can take longer to install each pile than traditional methods, lengthening the job and pushing costs up.
On many projects, a traditional rig will be the best option and noise from site operations must then be controlled in other ways. One method that has become increasingly popular in the UK recently is the use of acoustic barriers designed to be installed directly on piling rigs.
Hushtec, a New Zealand-based company which arrived in the UK in 2019, specialises in acoustic enclosures and noise barriers for mobile equipment.
Although earplugs of ear defenders will protect the hearing of site workers, high noise levels beyond the site boundary are often problematic, says Hushtec technical consultant Caleb Shaw.
聽鈥淲hen there鈥檚 a lot of pedestrians present that鈥檚 very different situation from a site where everyone is wearing noise protection. You need to use some kind of mitigation. You can use a fence or you can move it to where the actual noise source is,鈥� says Shaw.
This article was first published in the May 2026 issue of 麻豆社 Magazine. Sign up online.
Hydraulic breakers are among the noisiest machines on a construction site. But with one of Hushtec鈥檚 enclosures fitted, noise levels can be reduced by as much as 20db, says Shaw, although a 10db reduction is usually the target. And since the decibel scale is logarithmic, a 10db reduction equates to a halving of noise energy.
聽The other approach Hushtec takes to limiting sound at source is its acoustic shrouds. 鈥淭hat started when someone had taken one of our acoustic blankets, and used a webbing strap to wrap it around the rig,鈥� explains Shaw.
鈥淲e saw that and thought, we could do a tidy version of that. The early version
was on a frame hanging down from the pile rig itself.鈥�
Hushtec has since developed a modular system. Each piece is horseshoe-shaped and sits in front of and around the rig. These can be stacked on top of each other. Shaw says this is more effective at noise shielding.
It鈥檚 also a quicker way of working. 鈥淓ach part of the frame can be lifted apart to another area of the site. Once they finish a pile, they can move to the next much quicker because it鈥檚 so much faster to assemble.鈥�
Techniques like this were used on Canada鈥檚 Surrey Langley Skytrain project linking eight stations in the Vancouver suburbs of Surrey and Langley. 鈥淚t鈥檚 over 480 columns, there鈥檚 a lot of piles, some of them are 100m deep,鈥� explains Shaw.
鈥淭he alignment runs through urban and suburban areas, so noise management was a serious consideration.
鈥淲hen they were testing it unmitigated they were hitting 98db. The acoustic consultants said we need to get it to 84db. They actually achieved 77db.
That鈥檚 a massive drop,鈥� says Shaw.