Mott, Hay and Anderson (MHA) was a successful 20th century firm of consulting civil engineers based in the United Kingdom.
Early projects included the reconstruction and extension of the City & South London Railway, the building and extension of the Central London Railway, the construction of lifts beneath St Mary Woolnoth church at Bank Underground station, the underpinning of Clifford's Tower, the reconstruction of Southwark Bridge and the widening of Blackfriars Bridge.
In 1920, Basil Mott joined forces with Sir Maurice Fitzmaurice and John Brodie to advise on the best way to build a new crossing of the river Mersey in Liverpool.
In the early 1970s, an alliance was formed with Australian consultants John Connell Group for the design and construction of the Melbourne Underground Rail Loop, opened in 1981.
The alliance continued with bridge and tunnel works across Australia and Southeast Asia, culminating in the formation of a joint venture company (Mott Connell) in Hong Kong for the design of infrastructure in and around Chek Lap Kok airport, including the Lantau Link.
In the 1980s the Blackwall northbound tunnel, which David Hay had worked on 90 years before, was refurbished by Murphy construction under the supervision of MHA.
The firm of Mott MacDonald has since expanded its field of operations far beyond traditional consulting engineering (for example, it currently runs the education department of the London Borough of Islington).
[citation needed] Mott, Hay and Anderson were heavily involved in the design and construction of the Channel Tunnel between France and Great Britain.
Despite the lack of funding, a short section of service tunnel was dug beneath the English coast through ground that had been filled with instruments to assess the performance of the TBM.
The bid by the Channel Tunnel Group and France Manche was successful: the two bidders joined forces and reformed as an operating company Eurotunnel and construction contractor TransManche Link.