Vienna Danube regulation

Detail view of the still unregulated Danube in Vienna in the year 1780.
Plan of the Danube dig for 1870-75 in a contemporary presentation.
Bond for the Danube regulation, issued 1. April 1870
Opening of the regulated Danube in 1875.
View from Kahlenberg hill over the Danube: with Danube Island between the New Danube (left) and the main Danube (right).

The Vienna Danube regulation (German: Wiener Donauregulierung) refers to extensive flood-control engineering along the Danube river in Vienna, Austria during the last 150 years. The first major dams or levees were built during 1870-75. Another major project was constructed during 1972-88, which created the New Danube and Danube Island (Donauinsel). Prior to regulation, the Danube in Vienna had been an 8-kilometre (5 mi) wide wetlands, as a patchwork of numerous streams meandering through the area (see maps).