PymmesBrook

The Great Cambridge Road, the A10, slicing through Enfield, was lined with radio manufacturers and pharmaceutical companies.  

http://www.gorge.org/a406/north.shtml
http://wikimapia.org/9596441/Great-Cambridge-Roundabout

Pymmes Brook, Edmonton

• During 2005/06, the Environment Agency strengthened the channel walls of a section of the Pymmes Brook which had been culverted within the former Tottenham Gas Works. Inspection of the culvert revealed a risk of it collapsing, putting 1,500 properties at risk of major flooding.
• The Environment Agency's work removed pressure on the existing culvert walls, allowing removal of the roof of the culvert and the associated flood risk.
• The restoration will encourage more wildlife and fits with the Environment Agency's policy to remove existing culverts and open up river channels where possible.
• The project cost was £1.9 million with an allocated £25,000 from the budget for environmental improvements in the area.

http://www.ciwem.org/knowledge-networks/panels/natural-capital/de-culverting-of-watercourses.aspx

Powys Lane 

This marked the boundary of the Walker Estate.  It was very beautiful and crossed Pymmes Brook.  There was a footbridge for pedestrians and a water splash for horses and carriages. All around beyond low trimmed hedges was farmland and haystacks of Broomfield Farm.  The Lane was made up and developed in 1907.

There was a small pond, Littler’s Pond, named after the last tenant of Broomfield House, where Powys Lane joined Broomfield Park and near there Broomfield  dairy farm. The pond disappeared in 1906/07 and the farm was demolished in 1912.

http://improvingourplace.co.uk/content/karl-brown-writes-local-history-project-undertaken-his-son

Starting point Cockfosters tube station. Having been brought up in the countryside, I was initially sceptical about the appeal of urban walking.
 http://londonwhenyourepoor.wordpress.com/2010/10/22/pymmes-brook-trail/

The Parks in this video are:

1) Broomfield Park

2) Arnos Park

3) Brunswick Park (Waterfall walk)

4) Pymmes Brook, Oak Hill

5) Oak Hill Park

http://www.youtube.com/watch?v=Mb6VqtudWWE

This thread got me thinking about the Moselle, it runs underneath Carbuncle Passage in Northumberland Park, then across Clendish Marsh, then into Pymmes Brook. I took the dog out this morning, I think I've found where it goes into Pymmes Brook. I also think I've found a little bit of it where it comes out into the open, before it goes under train tracks at the Victoria Line depot (photos to follow).

http://www.urban75.net/vbulletin/threads/219754-London-s-lost-tunnels-and-rivers

Returning to the subject of the course under The Green, I have been looking at the 1867 and 1894 O.S. maps more closely and realising what had been staring me in the face. The maps indicate that the brook ran south along the east side of what became The Broadway. It then turned east to run just south of Knight's Lane and follow today's course. I had been thinking that a potential diagonal course under The Green was a little odd given the massive developments above it but had overlooked the obvious. It would explain why The Broadway was so broad for starters! The photo on the left shows a 1909 view with Salmon's Brook clearly in the open though it isn't visible in photos of the New Road junction dated 1910 so that could be when it was covered over.

Having just walked in this area I realised that a course south of Knight's Lane would take the brook straight under the swimming pool and certainly a picture above does show the brook emerging from that direction though it could change direction once underground. I don't think Knight's Lane has moved much so either it does indeed go under the pool or they have moved the brook!

Since writing the above I have seen it confirmed that the brook does indeed go under the leisure centre and that there are plans to divert it behind the police station when the leisure centre is replaced by a superstore (to be occupied by Asda). This was once talked of for 2004/5 but is more likely to be 2007 at earliest. Presumably this will all be underground which is a bit of a shame.

Something else I hadn't realised, and what led me to piece this together, was that somewhere under the site of the old Town Hall a second stream splits off from the brook to run south beyond Osman Road and then dogleg away to the south-east. There are modern roads called Brookfield Road, Brookside Road, and Brook Crescent near its course. This stream turned south to run along the west side of Montagu Road and join Pymmes Brook. On the 1801 enclosure map there is also a suggestion of a stream joining this just where it turns away from the line of the high road and I wonder if this might explain the curious alignment of the south end of Shrubbery Road.

Lesley Andersen, of the Montagu Road Flood Action Group, has kindly confirmed my assumption that this branch of Salmon's Brook still exists in a culvert though it now operates as an overflow system which channels water away from the main course at The Green when the brook is running high. This channel no longer feeds directly into Pymmes Brook as it once did as this historically caused flooding across and on both sides of the North Circular Road. Instead it has been diverted into the Intercepting Drain which carries it under the railway line to feed into Pymmes Brook further downstream. The culvert runs under the Police Station at The Green and was grated over when it was built, presumably for security reasons. Lesley would be interested to know if anyone knows anything about this as neither the council or the Environment Agency claim to be the body to have authorised this work

http://lower-edmonton.anidea.co.uk/transport/watercourses/salmonsbrook.html