In August 1849 the MCS appointed Joseph Bazalgette to the position of assistant surveyor. He had been working as a consultant engineer in the railway industry until overwork had brought about a serious breakdown in his health; his appointment to the commission was his first position on his return to employment. Working under the chief engineer, Frank Foster, he began to develop a more systematic plan for the city's sewers. The stress of his position was too much for Foster and he died in 1852; Bazalgette was promoted into his position, and continued refining and developing the plans for the development of the sewerage system. The Metropolis Management Act 1855 replaced the commission with the Metropolitan Board of Works (MBW), which took control of the sewers.