AT A GLANCE
Why go?
A huge sheet of water you can see but rarely walk beside, the William Girling Reservoir is one of the great storage basins of north-east London. Formed by a long earthen embankment in the Lea Valley, it holds drinking water drawn from the River Lee Diversion and belongs to the pair of Chingford Reservoirs it shares with the nearby King George V Reservoir. Set against a flat industrial and wetland backdrop, its scale is striking: roughly 334 acres of open water enclosed by a perimeter of about three and a half miles.↗↗
What makes it worth a detour is its double story as both an engineering landmark and a haven for wintering birds, all viewed from the paths that ring it rather than from the water itself. The reservoir has no public access onto the basin, so the appeal here is a glimpse of a vast working water store and the wildlife it shelters, framed by the Lea Valley Walk towpath and the margins of Chingford and Ponders End.↗↗
A water store built against the odds
The idea for a reservoir in the Lea Valley dates back to an 1893 plan for London's water supply, but construction only began in 1936, led by civil engineer Robert Wynne-Edwards for the Metropolitan Water Board. It was a pioneering site: mechanical scrapers and bulldozers were used in British dam building for the first time, and progress was fast. That speed proved dangerous. In 1937, when the partly formed embankment at the north-west corner had reached about 23 feet, a 66-foot-wide section slipped, dropping over two feet and sliding forward some 13 feet before any water was stored.