Engineering Wonders of the World
Volume III

THE WORLD. Mansergh, M.Inst.C.E., and Mr. Martin supply Brad- water of the Bradford’s Supply. able curtain extending beneath the dam from end to end, and terminating in the hillsides. From the bottom of the curtain wall to the dam’s crest the overall height at the centre of the dam is 212 feet. THREE PIPE LINES OF THE BIRMINGHAM AQUEDUCT AT THE CROSSING OVER THE STAFFORDSHIRE AND WORCESTERSHIRE CANAL, NEAR COOKLEY. {Photo, by courtesy of Messrs. J. Mansergh and Sons.) The bridge is on the hydraulic arch principle. Only two of the three pipes are in use at present. At some river and stream crossings the third pipe was built in at the outset. Another important scheme is that which will ford with the Nidd, stored up by a huge dam built across the river valley at a point 32 miles distant from the town. The aqueduct, which cost over half a million sterling, involved the driving of 6 miles of tunnel — one tunnel, that through the Greenhow Hill, being well over a mile long. As on the Derwent and Claerwen, other dams will be built and more water impounded when the demand comes for an increase in the supply. [Note.—Thanks are due to Mr. Walter Deacon, Assoc.M.Inst.C.E., for assistance given in connection with this article; to Messrs. James Mansergh and Sons for supplying a number of the illustra- tions ; and to the Manchester, Birmingham, and Liverpool Corporations for permission to reproduce the sketch maps of the aqueducts.] 192 ENGINEERING WONDERS OF The main aqueduct runs from the Howden reservoir to the service reservoir at Ambergate, whence the water is distributed to the towns of Derby, Leices- ter, and Nottingham. In its length of 30 miles there are 4 miles of tunnel 6J feet in diam- eter, 8| miles of cut-and-cover, and 17| miles of 45-inch. steel pipe. The Leicester pipe is 33 inches, the Nottingham pipe 29 inches, in diameter. The branch between the service reservoir at Ambergate and Sheffield includes a tunnel 7,623 yards long. The cost of carrying out the scheme is estimated at £6,000,000 ster- ling.