Following cholera, typhoid and yellow fever epidemics, city officials commissioned the English engineer John Batemen to plan a water purification system – the first of its kind in the Americas – to meet the needs of the city's rapidly growing population. This palatial waterworks building, completed in 1894, housed the water tanks. On the first floor is the quirky Museo del Agua y de la Historia Sanitaria with a collection of ornate tiles, faucets, ceramic pipe joints and old toilets.
Topped by French-style mansard roofs, the building's facade consists of 170,000 glazed tiles and 130,000 enameled bricks, all shipped from Europe and assembled here. It still houses the offices of Argentina's state water company AySA, whose customers come here to pay their utility bills. Guided visits offer a backstage glimpse of the building’s inner workings.