Thirlmere Aqueduct

The Thirlmere Aqueduct is a water supply system in Cumbria and Lancashire that carries water from Thirlmere Reservoir to Manchester. It stretches 154.3 kilometres and includes tunnels and cast iron pipes. The route passes through hills and valleys, crossing into Greater Manchester near Salford and Trafford. The aqueduct was built between 1890 and 1925 by Manchester Corporation Waterworks to supply up to 250,000 cubic metres of water daily. John Frederick Bateman advised on the project after earlier water sources proved insufficient. The dam at Thirlmere holds 37.4 million cubic metres of water when full. The aqueduct drops about 30 centimetres per kilometre, allowing water to flow by gravity alone at 6 kilometres per hour. A walk along parts of the aqueduct reveals its engineering details. The cut-and-cover sections use concrete channels about 2.2 metres wide and high. Near Dunmail Rise, a 6-kilometre tunnel was bored with precision, meeting almost exactly in the middle. Some sections were rerouted during motorway construction in the 20th century. The water takes just over a day to travel from the Lake District to Manchester.