The Masch Lake () is an artificial lake situated south of the city centre of Hanover, the capital of Lower Saxony, Germany. Spanning an area of , it is the largest body of water within Hanover and a popular recreation area as well as venue for numerous water sports. Name The name of the lake stems from the so-called , or simply , meaning 'swamp'. This is the historical description for the area in which the lake was built, that was in a deep-lying floodplain of the Leine river. Construction 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