Design Creating a lake in the wide river valley of the
Leine river near
Hanover was first considered during the late 19th century. This tied in with the by-then necessary dyking of the
Leine and
Ihme rivers, which would regularly flood the city after snow melted in the
Harz mountains in spring. The creation of a lake could reduce the threat of high water levels and put the Leine's river valley area to better use. Over the course of the following decades different designs emerged, from small to large, such as situating a shooting range () on an island within the lake. In September 1925, the newly elected city mayor
Arthur Menge commissioned a water engineer and professor at the Hanover Technical College (now
Leibniz University Hannover), to work out the details of the construction of a lake together with the city's building authorities. Franzius was to be responsible for the designing of the hydro-engineering and hydrological elements of the project, while the city authorities, led by Karl Elkart, would handle the urban development aspects. In contrast to the original idea that the lake be dug down into swamp land and then be supplied with water from the Leine, a new proposal emerged to build the Maschsee above the swamp in a bowl-like structureraising it higher than the water level of the Leineand having it be filled using a system of water pumps. This would eradicate the potential problem of accumulating mud through flood waters. Franzius created a final design that proved both effective and financially acceptable, whereupon the city authorities provided a grant of 14,000
Reichsmarks in January 1926 toward attempts to seal the basin of the proposed lake. Despite the plans being completed it nevertheless took roughly eight years until the beginning of the 1930s for work to commence. The three main factors behind the creation of an artificial lake in the
Leine river valley were: • The embankment of the
Ihme flood channel • The creation of a local recreation area close to the city that provided the opportunity for water sports • The elimination of high unemployment levels (which in 1932 was 58,000 Hanoverians) through programmes of public works One factor against construction of the lake was the nearly
Bismarck Tower that stood in the centre of the proposed water feature. Here,
paramilitary marches took place, and it was the site of a
book burning in 1933. The landmark was eventually demolished in 1935 during the course of the lake's construction.
Job creation In the 1930s, the era of
the Great Depression, the city of Hanover lacked the necessary finances to commence the Masch Lake project, even though the project had already been planned at the time for some ten years. The project was favourable for the
Nazi Party that came to power in January 1933 as it would help reduce unemployment levels, which was a central theme of their propaganda. On 28 November 1933 the project was approved at a meeting of the city council. On 21 March 1934 the first ground was broken in the Leine swamp. Despite the unsettled financing of the project, it provided many people with work. Driven by the harshness of the economic situation of the time, they took on tough working conditions and low pay which was barely above unemployment support. During construction, 14 locomotive trains with 365 tipping wagons were used along a track, as well as diggers and 5
crawler tractors. Many workers though had to supply their own tools. Initially there were 100 people working on the project, but by completion 1,650 people had been involved in the excavation of roughly of earth to create the lake basin. With the Masch Lake project fully completed by early 1936, the official opening took place on 21 May 1936. Hundreds of thousands of Hanoverians and guests looked on from the edge of the lake as the event began with the then-typical trooping of the
Nazi Party. In addition some 6,000 sporting persons took part in a rally along with the armed forces and public officials. Just a few years later, during
World War II, the lake was covered up with canvasses and fake landscapes created on floating islands in an attempt to confuse
Allied bomber pilots regarding their whereabouts during
air raids on Hanover. ==Water supply==