The story of Stephenson's vaults at Camden Come hell or high water

The story of Stephenson’s vaults at Camden Come hell or high water

It symbolised the coming of the electric age: ‘new’ Euston – a monument to the 1960s. Out went the station’s Doric propylaeum and glorious Great Hall, products of Philip Hardwick and his son; in came bleak concrete and what a critic called “tawdry glamour”, brought to us by British Rail’s anonymous architects. Thanks for that. There was of course an outcry to which John Betjeman lent his voice, leading to the formation of The Victorian Society and today’s conservation movement. But the price for progress – fast and frequent electric trains connecting London to the North – was the demise of original Euston and all that it stood for.

Electrification has actually been with us much longer than you might think. Volk’s Electric Railway was the first in Britain, opening along the seafront at Brighton in 1883. It still runs in the summer months. By then, Euston had been serving travellers for 46 years at the southern end of Robert Stephenson’s London & Birmingham Railway. As you’d imagine then, the station’s inaugural services were steam hauled, but only as a temporary measure. It was intended that trains would arrive under gravity and depart by rope; locomotives would not venture any further south than the originally-planned terminus at Camden Town, from where a mile-long extension descended into Euston on gradients as stiff as 1:66.

A watercolour by J C Bourne captures the vaults under construction.

Operationally, this method of working relied on both expertise and nerve. Witness the events of Thursday 13th July 1837 when the Railway’s directors took their friends on an experimental trip of 25 miles from London to Boxmoor, a week ahead of the official opening. The train of 11 carriages had been delayed on its return leg by boiler problems and a derailment, but worse was to come.

At Camden, the train was handed over to the bankrider who took charge of it down the incline, applying the brakes as necessary. His control was, however, somewhat lacking. The leading carriage struck the wall at the end of the line with “frightful force”, “dashing it to atoms, and causing a rebound which frightened all and damaged not a few”. Noses were broken, teeth lost and sprains occasioned; Sir John Reid and Lord Hatherton suffered injuries to the face. This was not an auspicious start.

Departure time

Outbound passengers emerged from Euston’s entrance hall into the train shed where a policeman would greet them, performing a ticket check before pointing out their allocated carriage. On hearing the signal bell, the officer shouted “Take your places ladies and gentlemen”, prompting those dawdling on the platform (or ‘promenade’ as they knew it) to hastily find their seat. Following a second signal was a call of “All right”; thereafter the train descended gently onto a ‘terminal plane’ which encouraged it to gather some momentum before the climb up to Camden, and did the opposite for those coming down.

Onlookers watch on as a train is hauled up the incline towards the huge chimneys betching smoke from the boilers.

Located alongside the first overbridge was a large wheel, around which ran an endless rope made from tarred hemp. Costing £460, this was a substantial achievement in itself: 4,080 yards in length, with a diameter of 2¼ inches and weighing the best part of 12 tons. On arrival here, the bankrider attached the train to it using a ‘messenger’ – a short length of rope which he held tightly around a hook on the front of the leading carriage, thus allowing a speedy release at the top. The process took “a very few instants”.

Accommodated in one of the bridge’s smaller arches was another policeman, responsible for operating the equipment which communicated a train’s readiness to the engineer at Camden Town; he started the stationary engines which hauled it up the incline. The signal was transmitted by pneumatic telegraph – similar in principle to a gasometer – forcing air through a pipe to the engine house in about four seconds, with sufficient force to sound a small organ pipe. And thus the journey began in earnest, reaching speeds of 25mph.

Drive and tension

Although the stationary engines were hidden beneath the railway, their location – just north of the Regents Canal bridge – could not be missed. Marking the spot were two chimneys, 132 feet in height, built adjacent to boiler rooms on either side of the railway. Between the central tracks, a spiral staircase provided access into expansive subterranean vaults, the arrangements therein being “on the best known principles, everything kept in the greatest order and cleanliness.”

At the foot of the steps was a room containing two low-pressure condensing beam engines on its eastern side; these were ordered from Maudsley Sons & Field of Lambeth at a cost of £5,150 and each generated 60HP. Only one was worked at a time, the other being available in case of breakdown or repair.

Having entered through a slot in the roof, the endless rope was wrapped three times around the driving wheel, 20 feet in diameter, and an associated pulley before entering a chamber housing the tensioning system. This incorporated a wheel mounted on a carriage which was drawn back along rails by a weight suspended in a well. Problems with this mechanism prompted in the sinking of a second well – 30 feet further back – two years after the line opened. The rope then entered the sheave room where it encountered the return wheel.

Coal for the boiler arrived by barge and was brought from the canalside on a tramway, through a short tunnel which entered the coal store – parallel to the tensioning room – at springing level. The tramway continued forward on cast iron beams, allowing the coal to be dropped into compartments below.

Beyond the coal store’s north-east corner was an open-topped pit containing a pair of marine boilers, used to raise steam for the engines at a pressure of just 4½lb/inch2. Perhaps unsurprisingly, this proved insufficient and a second pair was installed in a vacant boiler pit on the opposite side of the railway in 1838.

The vaults are symmetrical around a central passageway, but the other half – intended for use by the Great Western Railway – remained largely unused, the GW belatedly choosing to adopt an independent route into Paddington having failed to negotiate suitable leasing arrangements for a shared terminus at Euston.

High water mark

As trains became longer to deal with growing traffic levels, the need to divide them for haulage up the incline created an operational bottleneck. And so in July 1844, rope gave way to banked steam locomotives for outbound journeys, although gravity working continued for services into the capital for another 13 years.

Having succumbed to redundancy, the winding equipment at Camden was auctioned in 1847, the engines finding their way to a flax mill and Russian silver mine. Londoners were doubtless glad to see the chimneys dismantled, having contributed briefly to the city’s chronic pollution. In the mid-1850s, a tunnel was driven across the southern end of the vaults to connect the adjacent goods station – where horse power was prevalent – with stables on the opposite side of the railway.

Inside one of the tensioning rooms after the flood water had been pumped out.

No plans have been found detailing the arrangements Stephenson made for draining the vaults – whether a gravity system or continuous pumping – but it’s fair to presume he focussed much attention on the matter, as he had elsewhere. What’s certain however is that abandonment brought the problem of flooding, one which has persisted to this day. Typically the depth of water reaches 4 metres.

Tracks A, B, C, D, X and E: if you ever pass through Camden over one of these lines, the vaults will be playing a critical supporting role, with just 1.5 metres between soffit and sleeper. You’ll understand then why British Rail instigated a visual examination regime in the late 1980s, involving a complete dewatering every three years. When this was last done by AMCO Rail in 2014, it took a fortnight to discharge the floodwater into the disused Up Empty Carriage Tunnel which was pushed beneath the vaults in 1922. Within six weeks, the water had returned to its previous level.

Checks and balances

Whilst visual exams continue to provide reassurance that the vaults’ condition remains fundamentally fair, there is a recognition from an asset management perspective that detailed examinations need to be introduced. To that end, a team from Network Rail LNW Civils Special Projects arrived on site in February, its remit being to clear the vaults completely before putting in place permanent lighting and pumps. Benefiting the team is a pre-existing compound 300 metres to the north.

From the outset, the vaults were deemed a confined space due to the potential for toxic gas pockets and uncharted wells. Bridgeway Consulting was commissioned to report on the likely risks and implement appropriate safety measures, specifically a rescue team, signing-in point, periodic radio checks, gas monitoring and an extraction fan to deal with plant fumes. All members of the workforce undertook CS1 training for self-rescue purposes. Around a dozen men laboured underground at the height of the works, enduring conditions which might charitably be described as unpleasant.

Three two-inch sump pumps were deployed to remove 8,000m3 of water. This was done slowly – over three weeks – to prevent any damage to the sidewalls caused by a sudden loading imbalance. Thereafter, scaffolders erected a HAKI stair tower in the east-side boiler pit to serve as the main manpower access. A second one was installed at the south end of the coal store, creating an exit route to the canal towpath.

The central passageway, looking towards the engine room.

Left behind after dewatering was silt; lots of it. Working adjacent to the running lines and overhead line equipment, Readypower supplied a long-reach telehandler with electronic boom and slew restrictor to lower a micro-excavator and dumper into the vaults via the boiler pit. Tonne-bags were loaded and lifted out, to be stockpiled thereafter in the compound prior to despatch. In places, the silt was over 2 metres deep and heavily contaminated.

With 600 tonnes removed, what remained was effectively a thick soup, for which the excavator proved unsuitable. Attempts to use a jet-vac resulted in its filters getting clogged with small pieces of detritus, so attention turned to a super-absorbent hydrogel – supplied by Siltbusters – which solidified it sufficiently for digging out as a bulk material.

Throughout the vaults, narrow ventilation shafts are apparent in the roof. For the most part, these are capped – buried below the railway – and one of the project’s key objectives was to determine their surface location. This was done by recording GPS coordinates which were then mapped across the railway during Saturday night possessions. Several were found in the Up cess, allowing the concrete capping slabs to be replaced with GRP catchpits. This has helped to moderate the water ingress and bring in some welcome natural light.

Interest rekindled

Now Grade II* listed, Camden’s winding vaults form part of the area’s rich historical landscape, alongside the portals of Primrose Hill Tunnel, the former horse hospital and Roundhouse. Not surprisingly then, considerable local interest exists in securing the vaults for public use, combining a heritage centre and restaurants with exhibition and performance space. The idea is gaining traction, with all the right people making all the right noises. Not to be underestimated though are the huge financial and technical implications.

And then there’s HS2. Current plans propose a twin-bore tunnel passing 18 metres below the western edge of the vaults, bringing with it a need to fully understand their layout, including the wells. Also, the intention to create a Road Rail Access Point here requires a determination of the vaults’ loading capacity. To address these issues, an early task once the silt clearance is concluded will be to progress a 3D laser scan and full structural survey, the brickwork first having been jet-washed to reveal any defects.

Looking through the tunnel which was used to discharge coal into the store rooms.

High-speed rail will open another chapter in the metamorphic story of Euston Station. When its first train departed in 1837, there was no standard time: the capital’s clocks were set 7 minutes 15 seconds ahead of those in Birmingham. Soon, just 49 minutes will separate the two cities, such is the transformational impact railways still have two centuries later. And a fitting accompaniment to HS2’s arrival would be the re-emergence of Camden’s vaults, celebrating a historical role that was no less revolutionary.