Other work between the wars included the standardisation of the electricity supply in Derbyshire and Nottinghamshire, and the construction of tunnels and escalators for the London Underground. Extensive overseas work started in 1924 when Balfour Beatty took over the management of the East African Power & Lighting company; construction work included hydro electric schemes in the Dolomites, Malaya and India, power stations in Argentina and Uruguay, and the Kut Barrage on the Tigris in Iraq.