Before he designed the present system, London had a patchwork and rudimentary system of badly pitched combination sewers and storm drains that delivered both rain ater and sewage into the Thames. In 1858, a combination of very warm weather and a tidal anomaly that kept area water more stagnant than usual combined into something called then and now "The Great Stink." The eye watering, nausea inducing stench was so bad that Parliament had to go out of session. At last, London residents and government offiicials alike were willing to put up with the expense and disruption that constructing a modern sewer system would entail.
Sir Bazalgette was definitely the man for the job. Not only was he an amazing engineer, he also overbuilt the system to handle the much larger, future London he was sure would come. He used the hardest fired brick he could find in its construction and yes, it is still beautiful, the vaulted brick ceilings over a system that has never exceeded its capacity AFAIK.
You Tube has some good videos on "The Great Stink," some of which give quick looks at Sir Bazalgette's actual sewers.
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