(Signal Books, 2016. £9.99)

Jon Newman has written a timely account of the river that once flowed from the Crystal Palace ridge through Dulwich and via Herne Hill to the Thames and is now largely underground. Lost rivers form a part of the optional ‘Going Underground’ unit recently added to the curriculum for London schools, and the London Wildlife Trust’s ‘Lost Effra’ project uses sustainable planting schemes in the area to alleviate flooding caused by rainfall.

The author focuses on the two chief branches from Upper and Lower Norwood and the main river which starts where they join just north of Thurlow Park Road and west of Croxted Road. A particularly useful feature of the book is the itinerary with their routes shown on specially drawn modern street maps, blue lines superimposed on present-day photographs and detailed descriptions.

The first part of the book is a thoroughly researched discussion of the history of the river, in particular two major diversions, the earliest by Bermondsey Abbey to connect it to the Thames at Vauxhall rather than Rotherhithe, and its transition in the nineteenth century to an underground storm relief sewer with the flow diverted to the Crossness Pumping Station via intercepting sewers. The Effra Branch had a significant effect on Dulwich by drying up the watercourse from Thurlow Park Road to Herne Hill in normal times. However it was never capable of dealing with exceptionally heavy rainfall as some residents know to their cost, especially in 2004, and a considerable investment in flood relief measures has taken place recently in response.

This book is the most comprehensive overview in print of the subject to date. With Martin Knight’s website section The Effra in Dulwich and its appendix on wells in the area, which concentrate on the geography (martindknight.co.uk), there is now a remarkable amount of information available, enough to satisfy the interest of pupil and public alike.

Bernard Nurse