Pymmes Brook


Pymmes Brook is located in North London and named after William Pymme, a local land owner. It is a minor tributary of the River Lea. The brook mostly flows through urban areas and is particularly prone to flooding in its lower reaches. To alleviate the problem the brook has been culverted in many areas. Part of it is a Site of Borough Importance for Nature Conservation, Grade II.

Course

The source of the brook are underground springs at Hadley Common which are mentioned in reference to the penultimate battle in the Wars of the Roses at the Battle of Barnet. At this point it is known as Monken Mead Brook before flowing in a south-easterly direction to merge with the River Lee Navigation at Tottenham. It flows through East Barnet, where it is joined by a small tributary, the Shirebourne brook before flowing through New Southgate, Arnos Grove, Palmers Green and Edmonton. After flowing through Pymmes Park the brook can be seen at Fore Street, Edmonton before it flows underground and emerges south of the North Circular Road at Angel Road, where it is joined by Salmons Brook. The brook then flows parallel with the River Lee Navigation in Tottenham Marshes until it merges with the Lea near Ferry Lane A503 and Tottenham Lock.

Parks

The brook can be seen in the following larger parks;
It also flows through a number of other open spaces, smaller parks, and greens.

Walking

The new, extended route of the Pymmes Brook Trail starts where the brook's headwaters rise on Hadley Green then follows its approximate course to its confluence with the River Lea at Tottenham Hale, where the trail joins the Lea Valley Walk.

History

The brook is marked thus on the Ordnance Survey map of 1877. In c.1200 it was called, Medeseye that is ' meadow marsh-stream ' from Old English mæd and sæge
During the Middle Ages, it was known as the Medesenge, in the late 17th century as Millicents brook then, by the late 18th century as Bell brook.

Pollution issues

Pymmes Brook receives most of its water from urban run-off as overland flow or via surface water drains and combined sewage outfalls. There is some overflow from Jacks lake. Jacks Lake burst its banks in the 1930s causing flooding in East Barnet with glasshouses and cows carried downstream! Following on from this event the banks and the first part of the channel was heavily reinforced with concrete. Water quality parameters are indicative of a high level of pollution, in particular, there are areas with misconnections resulting in very high levels of fecal coliforms. Cat Hill for instance often exceeds 1 million colonies of Eschericia coli per 100 mls of water. Macroinvertebrate families are good indicators of organic loading and both the BMWP scores and the more recent WHPT biotic index scores are very low, compared with a clean chalk stream like the River Mimram which has a biotic index of around 210. The best scoring area of the brook has never gone above 32. Channel sediments are also heavily contaminated particularly with heavy metals, lead, zinc, copper, and cadmium are all extremely high.