The extensive water usage at Chatsworth necessitated collecting and storing water and to do so three lakes were dug on the hill; the largest was what is now called Swiss Lake. Relying on gravity, an elaborate system of ponds, watercourses and pipes led the water to where it was required.
It wasn’t until the 6th Duke asked Paxton to engineer the Emperor Fountain that major changes were made to this gravity powered water system. An additional lake, the Emperor, which covers nearly 8 acres, was dug to a depth of about 1.8m and involved moving nearly 76000m³ of soil, an immense task bearing in mind that this was before the advent of mechanical diggers. To feed the lake a 2 ½ mile channel, the Emperor Stream, was dug across the moor to gather the rain that fell on the high ground. The pipe to the Emperor Fountain drops 122m from the lake. In places trenches, up to 4.5m deep, had to be cut through rock to maintain the gradient.
The lakes hold over 80 million litres and can be seen from the Stand Wood walks. Water from the Ring Pond flows over the Sowter Stone and down to the Aqueduct which was built by Paxton, c.1840, and is based on something similar which the 6th Duke had seen in Germany. The water continues downhill through Stand Wood and enters the garden above the Cascade Pond. Once the water has flowed through the various water features in the Garden it then proceeds on through the turbine which was installed in 1893, replaced in 1988, and which supplies electricity to the house. Finally the water joins the River Derwent.