Great Western Railway: Dawlish Sea Wall Resilience

The WaveWalker in Dawlish Video (video at the bottom of the page)

Five years on from one of the most extraordinary engineering visitors our coastline has ever seen with Beach Cams Man and Jack Brookes from Bam.

Summary

WaveWalker 1, a 1,000+ tonne walking jack-up platform, enabled the installation of 286 foundation piles and associated panels and concrete to create a far stronger sea wall beside Dawlish station, improving the resilience of the Great Western Railway along this exposed coast.

Operating through tidal cycles with heavy specialist equipment, the team delivered rapid, precise piling while managing strict weather windows, safety, and COVID-19 constraints. The scope was efficiently expanded by 42 additional piles during mobilisation, leaving a lasting legacy that protects trains and the community from future storms.

When WaveWalker 1 arrived in Dawlish on 8 November 2020, few people realised they were about to witness one of the most remarkable feats of marine engineering ever seen along this stretch of the South Devon coast.

By the time she departed on 25 February 2021, she had transformed the future resilience of the railway at Dawlish, installing the foundations for what is now a vastly stronger sea wall beside the station. This work underpins the Great Western Railway route on the section from Dawlish to Dawlish Warren, improving reliability along this exposed coastline.

This was not just a barge or a jack-up vessel. This was a 1,000+ tonne walking machine.

A Walking Giant on the Beach

Unlike conventional marine vessels, WaveWalker does not simply float into position and anchor. She lowers her legs onto the seabed and physically walks forward using hydraulic slide plates. In offshore terms, the platform functions as a jackup rig (often called a jack up barge), which—in simple jack up meaning—is a self‑elevating unit that lifts on legs to work safely in shallow water.

During departure, she faced a 300-400 metre walk-out , taking between 15 and 18 hours to reach safe floating depth. At times she achieved around 40 metres per hour , shifting roughly 2,400–2,500 tonnes of steel and machinery across the sand.

To the casual observer, it looked slow. To engineers, it was extraordinary.

What She Carried

On board was a serious amount of kit:

• 114-tonne piling rig
• 32-tonne custom cantilever designed by BAM
• Two piling gates
• Excavators
• A crane with a 39 metre boom and 93 tonne lift capacity
• Around 450 tonnes of BAM equipment

The unloaded vessel itself weighs about 1,050 tonnes.

Everything had to be precisely secured for sea travel using “sea fastening”, welded pad eyes, heavy chains and straps. Before departure, a warranty survey ensured every weld and restraint could withstand movement at sea.

Weight distribution was calculated in detail. Liquids were pumped between tanks below deck to maintain balance. A spreadsheet tracked every tonne.

Nothing was left to chance. All of it supported precision civil engineering.

286 Piles. 143 Panels. A New Future.

WaveWalker’s core mission was clear:

Install the massive steel piles that would form the backbone of the new sea wall beside Dawlish railway station, part of the sea wall at Dawlish.

In total:

• 286 piles installed
• Supporting 143 facing panels and recurve units
• Around 810 cubic metres of concrete placed within the piles
• Approximately 8,000 cubic metres of concrete used behind the wall structure

Once operations were running smoothly, the team were installing 5 to 8 piles per 24 hours.

And because WaveWalker could operate through tidal cycles, work continued far more efficiently than a traditional land-based plant would have allowed. These works strengthened the Dawlish railway and the adjacent railway station frontage.

Built for Storms

This entire operation existed because of storms.

The wall was designed around specific storm return periods, one in five year events and one in ten year events in temporary state. Weather monitoring was constant. For departure alone, a 48 hour clear weather window was required, with conditions assessed at five points along the south coast. Local Dawlish weather, swell direction, wind speed and overtopping risk were all scrutinised to protect live railway operations.

Significant wave height, swell direction, wind speed and overtopping risk were all calculated before a single movement was made.

Even fuel logistics were carefully controlled. The vessel consumed roughly 1,700 litres per day, delivered in double bonded fuel cubes lifted aboard at low tide.

This was heavy engineering operating on a live railway frontage, beside homes, businesses and a community watching every move.

The Crew Behind the Machine

On board were typically three WaveWalker crew:

• Barge Master
• Electrician
• Fitter

Working alongside BAM engineers and operatives, they turned a complex marine plant into a precision piling platform operating within metres of the railway station. A lead civil engineer worked with BAM civil engineering engineers to coordinate safety, logistics and sequencing.

Covid restrictions were in place at the time. Welfare facilities were separated. Operations were tightly managed. And yet, not a single Covid case was recorded on the job.

An Extra 42 Piles

Originally, the contract was to finish just beyond the wall return near the station. But while WaveWalker was in place, an additional 42 piles were added to the works.

Why? Because demobilising and bringing the vessel back later would have been inefficient and costly. With the machine on site, it made engineering and financial sense to extend the scope. Extending while mobilised also avoided additional sea wall cost later, keeping momentum on the Sea Wall Dawlish works.

That decision accelerated progress and strengthened this section even further.

A Visitor People Will Never Forget

For months, Dawlish residents and rail enthusiasts watched this giant steel structure walking along the beach. Drones captured her from above. Dawlish webcam streams and onlookers at Dawlish station documented every phase. Some of that footage had never been seen before.

When she finally departed at high tide, towed away under strict weather windows, it marked the end of a chapter .

But the legacy remains.

Every time a Dawlish train runs through rough seas, those 286 piles stand firm beneath the promenade for Great Western Railway passengers.

Five Years Later

Five years on, WaveWalker’s visit feels almost surreal. A machine weighing well over a thousand tonnes walked across our beach, installed nearly three hundred foundation piles, and quietly left.

And yet, without her, this section of the railway would not have the resilience it now has.

As you watch the embedded video below and browse the photographs from that winter of 2020 to 2021, remember:

You were witnessing history.

Heavy engineering at its most precise.

And a walking giant that helped secure the future of the South West railway line.

Q&A

Question: What is WaveWalker 1 and how does a “walking jack-up” work? Short answer: WaveWalker 1 is a 1,000+ tonne self‑elevating jack-up platform that can lower its legs to the seabed and physically “walk” using hydraulic slide plates, rather than simply floating and anchoring like a conventional vessel. Functioning as a jack-up rig, it lifts itself clear of the water to work safely in shallow, energetic coastal conditions. At Dawlish, its departure involved a 300–400 metre walk-out over 15–18 hours, at times reaching about 40 metres per hour while shifting roughly 2,400–2,500 tonnes of steel and machinery across the sand—slow to watch, but an extraordinary feat of controlled, heavy engineering.

Question: Why was WaveWalker brought to Dawlish, and what did it achieve? Short answer: The platform enabled rapid, precise installation of the deep foundations needed for a stronger sea wall beside Dawlish station, boosting the Great Western Railway’s resilience on the exposed Dawlish–Dawlish Warren coast. In total, the team installed 286 piles supporting 143 facing panels and recurve units, placed about 810 cubic metres of concrete within the piles, and used approximately 8,000 cubic metres behind the wall. By operating through tidal cycles, productivity reached 5–8 piles per 24 hours—far more efficient than traditional land-based methods—directly strengthening the railway and station frontage against future storms.

Question: How were weather, tides and safety managed on such an exposed, live railway frontage? Short answer: The works were designed around storm return periods (1-in-5 and 1-in-10 year events in the temporary state), with constant monitoring of significant wave height, swell direction, wind speed and overtopping risk to safeguard railway operations. Key moves, such as departure, required a 48-hour clear weather window verified at five locations along the south coast. Tidal constraints were turned into an advantage by using the jack-up’s ability to stay on station and work through cycles. Even fuel logistics—about 1,700 litres per day—were tightly controlled via double-bonded cubes lifted aboard at low tide. Despite COVID-era constraints, welfare was separated, operations tightly managed, and no COVID cases were recorded.

Question: What equipment did WaveWalker carry, and how was all that weight controlled? Short answer: On board were an 114‑tonne piling rig, a 32‑tonne custom BAM cantilever, two piling gates, excavators, and a crane with a 39‑metre boom and 93‑tonne lift capacity—about 450 tonnes of BAM equipment, atop an unloaded vessel mass of roughly 1,050 tonnes. Everything was sea-fastened using welded pad eyes, chains and straps, and verified by a warranty survey before sailing. Weight distribution was meticulously managed by pumping liquids between below-deck tanks, with every tonne tracked in a live spreadsheet—ensuring stability, precision and safety throughout.

Question: Why were 42 additional piles added during the project? Short answer: With WaveWalker already mobilised at Dawlish, extending the scope by 42 piles avoided the cost and delay of future demobilisation and remobilisation. Doing the extra work then kept momentum on the sea wall programme, delivered enhanced resilience sooner, and reduced the need for additional sea wall expenditure later.