Otto Intze (1843–1904)

Two engineering principles are named after the hydraulic engineer Professor Otto Intze: one relating to water towers and the other to dams. In water towers, which stored water and supplied it under pressure, he devised a system to distribute the weight of the tank and reduce the risk of structural damage. This involved a ring beam or ‘ringanker’ to ensure that forces acted vertically and were spread equally around the brickwork of the tower. He designed spherical tanks set on conical bases. In the design of masonry dams before the widespread use of reinforced concrete he introduced a wedge of earth (later known as the Inze-wedge or ‘Intz-keil’) to protect the toe of the upstream face at the point of highest pressure. He brought this together with several existing features into a model approach that included a triangular cross-section, a curved ground plan, waterproofing of the upstream ‘water’ face and drainage within the dam structure.

Intze was the son of a doctor and born in the small town of Laage near Rostock. He was apprenticed to the Riga-Dünaberg railway from the age of seventeen to nineteen before studying engineering in Hanover. He worked first for the authorities in Hamburg on dock engineering projects and then took a teaching post at Aachen University in 1870 and for nearly 20 years practised as the university’s architect. From around this time he was often consulted on the construction of water towers and dams to create new reservoirs for the growing needs of industry and population in Germany and Austria-Hungary.

He developed many water-supply schemes after surveying the requirements for water and the potential for storage and supply. When he died in 1904, of the schemes he had designed, 11 were completed, 12 were under construction and another 12 were in preparation. The first completed, in 1891, was the Eschbachtalsperre dam in North Rhine-Westphalia. His dam on the River Urft, completed in 1905, was at the time among the largest in Europe. By around 1910 several hundred Intze water towers had been built in Germany and elsewhere to supply water to railway depots and towns. The principles were also used for gas holders.