In 1898, a further reconstruction of the riverbed began near Gersthofen with the initially three-kilometer-long Lech canal for the construction of a power plant. The combination of a dam and a run-of-river power plant in the river that is common today was not yet technically manageable at the time. A large part of the river water was channeled into the first canal section at the Gersthofer Lech weir at the level of today's Augsburg garbage mountain, at the end of which the first large hydroelectric power plant on the Lech went into operation in 1901 with the Gersthofen power plant. Today, the 10 km-long canal branches off from the Lech at the Gersthofer weir and flows back into the river after the Gersthofen, Langweid and Meitingen hydroelectric power plants. These three hydroelectric power plants were added to the UNESCO World Heritage list on July 6, 2019. This would not have been possible without the Lech weir and the Lech canal.