It runs from a system of reservoirs in north Derbyshire, to Ambergate, where the route divides, the Nottingham Branch heading down the Erewash Valley route and the main route running continuing down the Derwent Valley, over the River Trent and hence to Leicester. The aqueduct is a combination of contour-following culverts, piped syphons across valleys, and bored tunnels through hills. South of Ambergate covered reservoir the line divides with continuous sealed gravity-powered syphons to Langley Mill (for Nottingham), and to Leicester. The Ambergate to Leicester syphon is the longest in the country.
Acts of Parliament
There are acts of parliament from 1899, 1901, 1904, 1909, 1912, 1920, 1927, 1935, 1938, 1944. After that, changes seem to be covered by "Orders" rather than Acts.
- The (original) Ambergate to Langley Mill line is in the 1904 Act, along with an almost total rerouting of the (so far uncompleted) Derby/Leicester line.
- The 1909 Act includes a rerouting of the Morley to Hopwell section. This may be after the original Leicester pipe had been brought into use.
- The 1927 Act includes the rerouting in Dethick Lea and Holloway parish. It also mentions Crich parish, so there may be a bit more involved.
There was an additional re-routeing at Langley Mill (c.1920s?), this takes it over the Erewash Valley railway line across allotments to the River Erewash above the weir for the Erewash Canal feeder take-off and then on to the original alignment.
Modern-era diversions have taken place on the Nottingham Branch with the A38 cutting. And on the Leicester Branch with the A50/M1J25 construction .