The Blackwall Tunnel
The Blackwall Tunnel was built by the LCC between
1892 and 1897 in response to the growing need for
improved free road communications across the Thames
in the East End. When the Metropolitan Board of Works
(MBW) was created in 1855 there were only three free
cross-river routes in London, at Westminster, Blackfriars
and London Bridges. By 1880 all of the other road
bridges downstream from Chiswick had been freed from
toll, (ref. 365) but there was still no provision for the two-fifths
of London's population living east of London Bridge.
During the late 1870s and early to mid-1880s the MBW
promoted various unsuccessful Bills for a new crossing.
Eventually, in 1885, an Act was obtained authorizing the
construction of Tower Bridge by the City Corporation,
and this was followed in 1887 by the MBW Thames
Tunnel (Blackwall) Act, which empowered the Board to
build a new crossing between Blackwall and Greenwich. (ref. 366)
Figure 243:
Blackwall Tunnel. Plan of c1904 showing the route of the northern end of the tunnel, the extent of the area cleared and developments associated with the tunnel scheme Key: 1, 2 Tunnel Shafts: A Entrance Gatehouse: B Tunnel Gardens: C Toronto Buildings: D Montreal Buildings: E Winnipeg Buildings: F Hudson Buildings: G Ontario Buildings: H Quebec Buildings: I Baffin Buildings: J Ottawa Buildings: K St Lawrence Cottages: L St Nicholas's Church: M Council Buildings: N Raleigh Playground: O Electric Lighting Station: P Midland Railway Hydraulic Pumping Engine House: Q Midland Railway Offices: PH public house
Sir Joseph Bazalgette, the MBW's Engineer, prepared
a scheme comprising separate tunnels for vehicles and
pedestrians. (ref. 367) However, with the transfer of municipal
power to the LCC in March 1889, a new plan was
prepared by Alexander Binnie, the LCC Engineer, for a
single tunnel large enough to accommodate two lines of
vehicles and foot-passengers. This was approved by the
LCC in 1891, and the tender of S. Pearson & Son
of Victoria Street, at £871,000, was accepted for its
construction. (ref. 368)
Design and Construction
Binnie's designs for the tunnel and the engineering
techniques used - tunnelling shield, compressed air and
cast-iron rings - followed the same principles as J. Henry
Greathead's City and South London Railway Tunnel of
1886–90 and two large contemporary tunnels: the Hudson
River Tunnel in New York, begun in 1879, and the St
Clair Tunnel in Canada, begun in 1889. However, at
over 6,000ft long, and with an external diameter of
27ft (to accommodate a roadway 16ft wide, with two
footpaths), Binnie's was the largest sub-aqueous tunnel
yet built, and was a bold undertaking considering the
difficult subsoil at Blackwall.
The tunnel route was planned to connect East India
Dock Road with Woolwich Road, crossing the Thames
between Northumberland Wharf on the north and Ordnance Wharf on the south. The proximity of the docks
and the availability of suitable approaches dictated its
slightly sinuous path. (ref. 369) Four vertical shafts were situated
where there was to be a change in line or level, the tunnel
running straight between them, save for an extra bend
on the northern side to avoid a main sewer and some
housing in Bedford Street (fig. 243). The tunnel shafts enormous double-skinned cylinders of iron - were constructed by the Thames Iron Works & Ship Building
Company of Blackwall, (ref. 370) and lined inside with glazed
brickwork (Plate 109a). Shafts Nos 1 and 4 were eventually fitted with spiral staircases for pedestrians, and
domed over with glass-and-iron roofs. The other two
shafts were reserved for administrative and working purposes (No. 2), and for ventilation (No. 3). Damaged by
bombing during the Second World War, in the late 1960s
the shafts were reconstructed in brick and concrete with
shallow-domed roofs of concrete slabs as part of the
improvements to the tunnel and the redevelopment of
Northumberland Wharf. (ref. 371)
Figure 244:
Blackwall Tunnel, section showing the construction
The Blackwall scheme was divided into three separate
and distinct sections: open approach roads with concreteand-brick retaining walls; cut-and-cover sections lined
with concrete and white-glazed bricks; and the cast-iron
tunnel, 3,083ft long, 1,220ft of which lay directly beneath
the river.
The tunnelling shield used at Blackwall was designed
by E. W. Moir, the contractors' engineer, and was built
by Easton & Anderson of Erith. (ref. 372) It was a development
of the design introduced by Marc Brunel for the Thames
Tunnel of 1825–43, and improved upon by Greathead
for the Tower Subway of 1869 and the City and South
London Railway Tunnel of 1886. A giant steel cylinder
over 19ft long, the shield was divided into sections to
allow as many as 12 men to make a simultaneous assault
on the work-face (fig. 246). The cast-iron lining was
assembled at the back of the shield and lifted into position
by hydraulic arms and secured in place by a solid bed of
cement 'grouting'. The interior was lined with 14ins of
Portland-cement concrete and faced with a granite plinth
and white-glazed tiles specially designed for the tunnel
by T. & R. Boote of Burslem (fig. 244). Granite sets were
used to pave the tunnel roadway, except in the section
beneath the river, where asphalt was used. The outer
ring of the shield was left embedded in the tunnel as a
permanent memorial. (ref. 373) Compressed air was used in the
tunnel during construction to prevent an inrush of water
from above. Safe levels of compression required the
tunnel to pass in places within 5–6ft of the river bed,
with only loose shingly ballast and gravel between the
heads of the workmen and the murky Thames above.
Compensation was arranged for any workmen injured
while working in compressed air and for the families of
any men killed, and hospital facilities were also provided. (ref. 374)
Progress of the Work
Work on the tunnel began in March 1892. By the end of
the year two teams of workmen were excavating the
approaches on both sides of the river, while a third was
driving piles into the river bed at Northumberland Wharf,
reclaiming land for the site of No. 2 Shaft. (ref. 375) (The wharf
was extended into the river to accommodate the tunnel
shaft, and a new concrete wharf wall was erected and
extended to meet the wall of the new Blackwall Entrance
lock.) Tunnelling proper started in the easier ground
south of the Thames, and work began on the main river
portion on the Kent side in September 1893. To prevent
compressed air from 'blowing-out' of the tunnel beneath
the Thames, a large artificial bed of clay 10ft thick and
150ft wide was dumped from hopper barges on to the
river bed. (ref. 376) Although some minor works were still to be
completed, the tunnel was officially opened by the Prince
and Princess of Wales on 22 May 1897. Most of the
vehicles using the tunnel during the first weeks were
dock and railway vans, and the new crossing became
popular with local workers on both sides of the river. (ref. 377)
Surprisingly few of the people connected with the
Blackwall Tunnel were Londoners. Although the LCC
asked Pearsons to employ local workmen, (ref. 378) the foremen
came from the provinces, particularly Yorkshire. The
iron tunnel lining was made in Glasgow by the British
Hydraulic Foundry Company, the bricks and tiles came
from provincial firms, the granite sets were from Aberdeen, and the asphalt roadway was laid by teams of
Italian workmen employed by the French Val de Travers
company. Alexander Binnie had been the LCC's Chief
Engineer throughout, with David Hay and Maurice
Fitzmaurice as Resident Engineers, and E. W. Moir
representing the contractors. (ref. 379) The Blackwall Tunnel
was the only free road-crossing of the Thames available
between Tower Bridge and the Woolwich Free Ferry (a
distance of nearly nine miles), and its construction had
been so successful that, at the time of its completion, the
LCC was already planning another large sub-aqueous
vehicular tunnel at Rotherhithe, and a smaller foot-tunnel
linking Greenwich with Island Gardens (see page 525).
Figure 245:
Blackwall Tunnel, plans and section of the north entrance gatehouse. Thomas Blashill, LCC Architect, 1896–7. Demolished
Ancillary Buildings
Entrance Gatehouses.
Binnie's original plans included
designs for a pair of simple Classical arches to mark the
entrances to the open approach roads and indicate the
maximum headroom in the tunnel. These were superseded by more ambitious designs by Thomas Blashill,
the LCC Architect, for two entrance gatehouses to accommodate the superintendent and caretaker of the tunnel
(Plates 109b, 110b). (ref. 380)
The north gatehouse was erected in 1896–7. Basically
rectangular in plan, with octagonal turrets at each corner,
it spanned the open approach road, with two bedrooms,
a living-room, scullery, larder and w.c. on the floor above
the archway (fig. 245). A third bedroom and a cistern
room occupied part of the roof space above. The houses
were built of light-brown sandstone with contrasting
bands of red sandstone. Pearson & Son were the contractors, but appear to have sub-contracted the work to
Dove Brothers. (ref. 381) The facades were decorated with shields
carrying the coats of arms of Middlesex, Kent, Essex and
Surrey, and commemorative bronze plaques by Singer &
Son of Frome. The gatehouses provided unusual Art
Nouveau silhouettes amid the working-class housing of
Poplar and the empty expanses and gas-storage tanks of
Greenwich Marshes, and the proximity of the East India
Dock Gateway on the north side no doubt inspired
Blashill to compete with it in architectural terms.
In 1899 public toilets were provided by the LCC in a
small building adjoining the north entrance gatehouse, in
a suitably sympathetic style. (ref. 382)
In 1958 the north entrance house and the toilets were
demolished during work on the approaches for the new
Blackwall Tunnel. The south gatehouse at Greenwich
still stands.
Tunnel Entrance Bridge Parapets
The entrance facades to the cut-and-cover portions of
the tunnel had fronts of polished red granite, with two
flights of stone steps leading up to the roadway to provide
easy access for local foot passengers. The design was kept
simple, the only surface decoration being fleur-de-lis
finials on the piers and an inscription along the top
of the parapet marking the completion of the runnel.
Ornamental electric lamps were provided on the staircases. Most of the parapet on the north side still remains
today, although the stone steps and attached walls and
piers were demolished.
Blackwall Tunnel Electric Lighting Station,Northumberland Wharf (demolished)
Since no public supply of electricity was available to light
the tunnel and its buildings, (ref. 383) the LCC decided in 1896
to build an electricity-generating station at Northumberland Wharf, adjoining Shaft No. 2 (fig. 243). (ref. 384)
This comprised buildings to house the boilers and
engines, a large fluted chimney (120ft high and 12ft
square at its base), a subterranean water-tank, and a
combined building for offices and stores (Plate 110a).
Designed by the LCC Engineer's Department and constructed in stock brick by Pearson & Son, (ref. 385) the buildings
were of a plain, Italianate style, with a main fenestration
of round-headed windows coupled in arched recesses.
The boilers and fittings were supplied by Fraser & Fraser,
and the engines and dynamos by Laing, Wharton &
Down. (ref. 386) The buildings were finished by mid-July 1897,
when the tunnel opened for continuous day-and-night
traffic. (ref. 387) (fn. t)
The plant was shut down in 1912 when the tunnel
was connected to the municipal supply, and in 1920 the
wharf and disused station were sold to Poplar Borough
Council for £11,000, and were then used as a refuse
depot. (ref. 389) The buildings were demolished during redevelopment by the GLC in the late 1960s. (ref. 390)
Blackwall Tunnel Duplication
Although adequate for the predominantly horse-drawn
traffic of the nineteenth century, the tunnel could
not meet the growing demands of twentieth-century
London's motorized traffic. In 1937 the LCC decided
to build a second tunnel c800ft downstream of, and
running parallel to, the existing tunnel. The new
tunnel was to be for south-bound vehicles only, with
the existing tunnel serving north-bound traffic and
pedestrians. Improved approach roads would require
the demolition of, amongst other things, the tunnelentrance gatehouse and Tunnel Gardens. (ref. 391) The LCC
(Tunnel and Improvements) Act of 1938 (ref. 392) authorized
the duplication of the tunnel and the acquisition of
land and demolition of property, but the Second World
War and the economic stringency which followed it
delayed work on the scheme until 1957, when the
Ministry of Transport authorized the LCC to begin
work on the new northern approach road and proceed
with necessary improvements to the old tunnel. Work
began in April 1958. (ref. 393)
The Northern Approach Road, 1958–60.
A new road
was designed for eight lanes of traffic, with two central
carriageways passing beneath the East India Dock Road,
and slip roads on either side. It was hoped that this 'semiclover-leaf interchange' would allow for an uninterrupted
traffic flow into and out of the tunnel and along East
India Dock Road, (ref. 394) but the Blackwall Tunnel remains
notorious for long delays. The new scheme also required
the construction of new roads and the upgrading of
existing roads linked with the approach. A new entrance
to the East India Docks was constructed, and the dock
wall was renovated and realigned. A joint tender of
£570,191 from Holland, Hannen & Cubitts and Fitzpatrick & Son was accepted by the LCC for the northern
approach works. (ref. 395) The new approach road was opened
on 27 June 1960, (ref. 396) and work then began on the second
tunnel.
The New Blackwall Tunnel.
The route of the new
tunnel was determined largely by the availability of
suitable sites to house the two caissons which would
form the permanent ventilation shafts. Sites were
selected in part of the South Eastern Gas Board's
works at Greenwich and in the former Midland
Railway's dock at Blackwall Yard on the Poplar side
of the river. Rectangular caissons of concrete and steel
plate were sunk on either side of the river and two
Greathead shields (previously used in the construction
of the Dartford Tunnel) were reconditioned and
assembled in the caissons. A special chemical compound
was used to secure the surrounding water-bearing strata
before tunnelling began, and the shields finally met
beneath the river in May 1964. (ref. 397)
The cast-iron tunnel was designed by Mott, Hay &
Anderson, and built by Balfour, Beatty & Company. Subcontractors for the specialist ground treatment were the
Cementation Company and Soil Mechanics-Soletanche
Ltd. The cut-and-cover and open approach sections were
designed by the LCC's Chief Engineer's Department,
with assistance from M. H. Ionys Hughes, Consulting
Engineer, on the design of the open approaches. Watertight reinforced-concrete was used throughout and the
contractors for this section were Kier Limited. Various
linings were used throughout the length of the new
tunnel, including Portland stone, precast tiled panels and
black terrazzo coping. The cast-iron sections were lined
with light-grey PVC-coated aluminium sheeting, with a
suspended ceiling of the same material in dark blue.
Figure 246:
Blackwall Tunnel. Longitudinal section of the tunnel under construction, with the shield at work in the clay. The cylindrical steel shield enabled up to 12 men to excavate the work-face simultaneously. The shield was then driven forward by hydraulic arms and rings of cast-iron, forming the tunnel-lining, were put in place in the space left behind
Contractors for the tunnel lining, roadway and services
were Balfour, Beatty & Company. The final cost of
construction of this stage of the project was approximately
£7 million. (ref. 398)
The tunnel was opened on 2 August 1967 by
Desmond Plummer, Leader of the GLC, at a special
double ceremony that also included the inauguration
of work on the Blackwall Tunnel Southern Approach. (ref. 399) (fn. u)
The old tunnel was then closed for improvements. It
was reopened on 4 April 1969 with a new electronic
signalling system designed to redirect 'overheight'
traffic. A month later the tunnel was finally closed to
pedestrians. (ref. 401)
Ancillary Buildings.
A squat, rectangular administration building was constructed between the two
approach roads on the Poplar side of the river, near
the entrance to the new tunnel. It is of concrete, on
two levels. Offices and a traffic-control room occupy
the upper level, with a garage and yard for maintenance
vehicles below. The contractors were William J. Jerram,
and building costs were £87,300. (ref. 402)
The ventilation plants and electrical equipment for
the second tunnel required two new buildings. The
curvilinear plan resulted partly from the need to enclose
four large circular fan housings and motors, and,
similarly, the tall aerodynamic air flows of the fans
influenced the sculptural elevation of the shafts (Plate
110c). The roof section consists of a shell of sprayed
concrete on a framework of stressed cables, and is
supported by a ground-floor section of Staffordshire
blue brick and glazing, surrounded by three successive
levels of precast flags, brick paving and asphalt paving.
The buildings were designed by the GLC's Department
of Architecture and Civic Design and constructed
under its supervision by William J. Jerram. The
ventilation plants were the work of the Midland
Heating & Ventilation Company of Birmingham, and
the combined cost for the buildings and ventilation
plants was £360,000. (ref. 403)