Chadwell Spring, the New River
Lee Valley, Hertfordshire, UK
Sir Hugh Myddleton
Water Supply/Pipes |
ICE reference number
photo Jane Joyce
Chadwell Spring and nearby Amwell Spring are the original supply sources for the New River, an early canal constructed to supply drinking water to the City of London. At Chadwell, the spring water comes through cracks in the underlying chalk and flows into a circular stone-lined basin.
Up the beginning of the 17th century, London was supplied with water by the River Thames or local wells and springs. As the population grew, this proved insufficient. In 1602, Edmund Colthurst (c. 1545-1616) proposed bringing water to London in open channels from Chadwell Spring and Amwell, which is 3km downstream. King James I granted a charter for the works two years later.
Colthurst's route would bring the water on a winding, almost-level course, nearly 65km to Clerkenwell in London. In 1605, work commenced and 4.8km of the canal was dug — before financial difficulties stopped the labourers. A Parliamentary Act of January 1606 enabled the Corporation of the City of London to restart the scheme and in March 1609 they appointed Welsh entrepreneur, goldsmith and Member of Parliament Sir Hugh Myddleton (1560-1631) to deputise for them.
Work on the New River began again in May 1609, with Colthurst as resident engineer and Myddleton superintending. The route followed the 30.5m contour on the west side of the Lea Valley, almost doubling the straight line distance to London. The water flowed under gravity all the way, falling only 5.5m in total (5 inches per mile).
Chadwell, which literally means 'cold well', is the natural location of a prolific spring, long in use by local inhabitants. After 1727, it was often referred to as St Chad's Well (after St Chad, Bishop of Lichfield), although its name does not appear to derive from the saint.
The basin at Chadwell, which was constructed as part of Colthurst's initial works, is 18m wide. The spring produces up to 18 million litres of water a day. In dry weather the flow can stop, so a weir at the river outlet has been included to prevent water flowing back from the canal.
The stone plinth placed at Chadwell Spring is inscribed: "Chadwell Spring, Conveyed 40 miles, opened 1608, repaired 1728".
In recent years Thames Water has introduced a water recharge system that enables surplus water in the winter to be pumped into the underground reservoir of natural chalk. It is pumped back into the New River when water is scarce.
Research: ECPK, JJ