When London's main drainage was completed north of the Thames in 1868, the Metropolitan Board of Works marked the occasion with a banquet held inside a sewage pumping station. Abbey Mills had been built over the previous three years by the engineer Joseph Bazalgette, working with the architect Charles Driver, laid out on a cruciform plan with eight beam engines, two on each arm. Its style has been read as Byzantine, Italian Medieval, Russian, Ruskinian Gothic and Moorish, and its twin ventilation chimneys, richly ornamented, rose more than sixty meters. The builder called it an elegant structure in a swamp and thought it might pass for a mosque or a temple.
Almost everything else Bazalgette built was buried, and the exception did not last the century. Steam gave way to electric motors at Abbey Mills in 1933, and the chimneys, redundant since then, were demolished in 1941 out of fear that a bomb strike would topple them onto the station. Sanitary engineering consolidated around criteria that could be measured, among them throughput, discharge quality and hydraulic gradient, and appearance registered in none of them. Treatment moved outward to floodplains, estuaries and municipal edges where land was cheap, and gravity did useful work.
