In the 1850s, the crucial parts of the water infrastructure in Istanbul were nearing a state of collapse, and complaints of deficient and bad water supply were of constant occurrence in the official ordinances and newspapers. Therein we find the Minister of Istanbul's Waterworks (su nâz?r?), Tevfik bey (d. 1859/ H. 1276), anxiously attempting to solve the problems of the city's water supply. His solution opened up one of the first corporate and institutional encounters between the Ottoman Empire and Europe. The scarcity of local capital led Tevfik bey to borrow money from Austro-Hungarian and French financiers for the rehabilitation of the dilapidated urban water supply systems of the Ottoman capital city. These foreign investors also sent hydraulic experts and engineers for the adoption of new technologies. Drawing on archival materials, local court records, as well as contemporary newspapers, this paper will examine the cultural, diplomatic, social and technological aspects of the continued encounters of a cadre of foreign hydraulic experts and local personnel, surveyors and peasants, entrepreneurs, political and technical elites in Istanbul during the second half the nineteenth century. By focusing on the relationship of this nineteenth-century Istanbul case to broader urban and social transformations, this paper seeks to facilitate historical comparisons between the interchange between local and foreign actors, the mutual constitution of the indigenous knowledge systems and expertise, pre-urban landscapes and urban infrastructures, and natural resources management and power unfolding in the Ottoman empire during the nineteenth century.