Aquifer Recharge: An Operational Drought‐Management Strategy in North London

The North London Artificial Recharge scheme, which comprises thirty‐seven wells and boreholes, is designed to boost resources during a drought. All sources discharge groundwater either to the Lee Valley reservoirs or the New River during the abstraction, which avoids the need for expensive on‐site water treatment and significantly enhances the cost effectiveness of the scheme. Fully treated drinking water provides the source of gravity‐fed artificial‐recharge water, via the normal distribution system. This paper describes the strategy which was introduced in 1997, in response to a deteriorating water‐resources situation. Abstraction occurred over a period of four months prior to the onset of autumnal winter rainfall. Daily abstraction rates peaked at 150 Ml/d, and a total of about 10 700 Ml were withdrawn.