One of architect Frank Lloyd Wright's most famous and visionary creations, the Fallingwater mansion in Pennsylvania needs $11m of renovation to save it from collapsing.

The house which is cantilevered over the Bear Run Creek in the Allegheny Mountains in Pennsylvania is dangerously close to falling into the river over which it is built, and requires substantial structural work which will start in November and is due to be completed by April 2002.

Open to the public since 1963 when it was donated by the son of the original owner to the Western Pennsylvania Conservancy, the house has been subsiding since its creation in the 1930s, due to design flaws.

The renovation work will be overseen by a team of structural engineers who have already worked on several of Wright's other buildings.