Geology Site Account

Historical site only

Between 1909 and 1911 excavations in the Lea valley at Chingford by the Metropolitan Water Board for the construction of huge new reservoirs produced a number of fossils. The main excavations were in post-glacial (Holocene) alluvium which covers the floor of the valley and consisted of layers of clay, marl and peat, the clay being used to provide material for the banks of the reservoirs. Below this alluvium was an iron-stained gravel about 3 metres (10 feet) thick dating from the last glacial period (the Devensian) and resting on London Clay bedrock.

The peaty alluvium produced numerous mammal bones and deer antlers but the most spectacular fossil was a very fine skull of an aurochs or wild ox (Bos primigenius). Aurochs were ancestors of our present day domestic cattle but were much larger and with their large horns they must have been a formidable sight, especially in large herds. Aurochs were very common during the latter part of the Ice Age and feature prominently in the world-famous 17,000 year old cave paintings of Lascaux, France. The Chingford skull was donated by the Metropolitan Water Board to Londons Natural History Museum in 1911. Also found was a tooth of a mammoth which must have come from the underlying cold-climate gravel.

During the course of the works the water board hosted visits by members of the Geologists Association in 1909 and 1911 which were combined with visits to the famous gravel pits at Ponders End nearby. The written reports of the visits describe the vast scale of the reservoir excavations which involved diverting the River Lea and obliterating county boundaries.

One of the finest skulls of an aurochs ever found in Britain was discovered during construction of the Chingford reservoirs and donated to the Natural History Museum in London. The skull is 60 centimetres (2 feet) long and shows an indent in the middle of