To bring fresh water to the city, his hydraulic engineer, Eugene Belgrand, built a new aqueduct to bring clean water from the Vanne River in Champagne, new huge reservoir near the future ParcMontsouris. These two works increased the water supply of Paris from 87,000 to 400,000 cubic metres of water a day. He laid hundreds of kilometres of pipes to distribute the water throughout the city, and built a second network, using the less-clean water from the Ourq and the Seine, to wash the streets and water the new park and gardens.

The population of Paris had doubled since 1815, with no increase in its area. To accommodate the growing population and those who would be forced from the centre by the new boulevards and squares Napoleon III planned to build, he issued a decree annexing eleven surrounding communes, and increasing the number of arrondissements from twelve to twenty, which enlarged the city to its modern boundaries. Beginning in 1854, in the centre of the city, Haussmann’s workers tore down hundreds of old buildings and cut eighty kilometres of new avenues, connecting the central points of the city. Buildings along these avenues were required to be the same height and in a similar style, and to be faced with cream-coloured stone, creating the signature look of Paris boulevards.

Napoleon III also wanted to build new parks and gardens for the recreation and relaxation of the Parisians, particularly those in the new neighbourhoods of the expanding city, Napoleon Ill’s new parks were inspired by his memories of the parks in London, especially Hyde Park, where he had strolled and promenaded in a carriage while in exile; but he wanted to build on a much larger scale.