Northern Ventilation Shaft To The Blackwall Tunnel Southbound

The Northern Ventilation Shaft to the Blackwall Tunnel southbound is a ventilation tower designed between 1961 and 1962 and built between 1964 and 1967 by the London County Council's Architect's Department Special Works Division, later that of the Greater London Council. The project was led by Eric Hayes, with Terry Farrell as job architect, and involved engineers Flint and Neill, the Cement Gun Company, and the LCC/GLC’s Engineer’s Department.

The structure comprises sprayed concrete (gunite) shells supported by stressed cables radiating from a reinforced concrete slab, set atop perimeter walls of blue brick and glass. The shell roof is supported from the slab, which houses instrumentation used to measure air pollution. A concrete grillage within the structure incorporates a spiral staircase and a crawl-way ducting system. This supports electrical installation, linking the motors from the switch room and transformers and providing an airlocked access to the tunnel beneath. The gunite shells were protected from corrosion with a coating of bitumen and cement paint, representing an early application of gunite as a primary building material rather than merely a repair technique, as it reduced the need for shuttering.

The tower's curved form was inspired by the architecture of Oscar Niemeyer, exemplified in his work at Brasilia. Terry Farrell, who was briefly employed by the LCC during the project’s design phase, drew a comparison between the structure’s “romantic” character and the “rugged machine aesthetic” he later adopted. The ventilation towers provide a stark contrast to the nearby Reuters Building and Robin Hood Gardens. The design is unique within Farrell’s wider architectural output, which subsequently favored influences like those of Louis Kahn.