London sewer system

Seven Wonders of the Industrial World

In the summer of 1858 the stench of the Thames, fouled by untreated sewage, became so severe that Parliament was forced to act, an event remembered as the Great Stink. Cholera outbreaks had already killed thousands, though the link with contaminated water was only gradually understood. The Metropolitan Board of Works appointed its chief engineer, Joseph Bazalgette, to design a system that would intercept sewage before it reached the river and carry it eastwards by gravity and pumping to outfalls downstream. Between about 1859 and 1875, his teams built some 132 kilometres of main brick sewers and linked them to many more kilometres of local sewers, using hundreds of millions of bricks. Great pumping stations, including Abbey Mills, Crossness, Deptford and Western, lifted sewage between levels, powered by steam beam engines. Bazalgette also combined the sewers with new embankments along the Thames at Victoria, Albert and Chelsea, creating roads, gardens and underground railway space above them. The system was so well planned that it still forms the backbone of London’s sewerage today, supplemented in recent years by the Thames Tideway Tunnel. Most of it is hidden and not open to visitors, but Crossness Pumping Station, a lavish Victorian engine house with restored engines, welcomes the public on selected days, and Abbey Mills can be admired from outside. Walking the embankments is the easiest way to feel the scale of the vision.