Account of the Annual Wildlife Ride organised by Cyclism (https://www.cyclism.org.uk/)
Meeting Point: Lavington Road, by footbridge (CR0 4PQ) Beddington. Led by Dave Warburton (Biodiversity Officer, London Borough of Sutton)
Sometimes a ride doesn’t fit into the normal expected format of pedalling a distance (short or long) to a destination and return. This ride focused on multiple stops in the locale, following the Wandle river which is well known to many, for it’s part played in both in industrial and natural worlds. It has been a constant thread running through four London boroughs, and through different eras. Now, it has become a pilgrimage for leisure walkers and cyclists to explore this ribbon of blue and green.
Led by Dave (a very big thanks for giving your time to explain much about the Wandle), the first point of interest was only short wheeling across the bridge to Richmond Green. Dave explained the source of the river – the chalk outcrop called the North Downs supplies clean water carrying calcium phosphate and supports particular species of plant, insects, fish, and birds. Twice the blue flash of a kingfisher caught our attention! The Wandle was canalised in the post war years, and remains constrained by the banks of concrete. Part of Dave’s work is to bring back a Wandle of natural form. Shallow banks, meanders, fast and slow moving water, gravel shoals, changes to weir heights allowing fish to migrate upstream more easily. The substantial flood management schemes, responsible for restricting the flow from doing what it does naturally, are difficult to undo with costs prohibitive. The north bank of the river will be changed from the vertical retaining wall to an edge with a shallow gradient.
After stopping for more informative insights, we crossed over the bridges where the two arms of the Wandle waters rejoin, and regrouped in Guy Road Recreation Ground. Dave identified the vegetation and pointed out the island formed from some small obstruction in the river bed. Bounded by houses, changing the course of flow from direct and straight channel to meandering flora and fauna rich waters isn’t an easy task.
Another pause along the Wandle channel, with Dave pointing out the water supplied to the Carew Manor Wetlands. Much of the changes proposed will bring more wildlife to the river, but the challenge to deliver this is complicated. Each of the four boroughs are responsible for their tract of the Wandle, with changes to each tract affecting the downstream sections. Computer modelling in both two and three dimensions is vital to show what changes can be made. If the old channel walls, or a weir, are altered then calculating the flood risk could mean mitigation for flooding has to be included in any proposals.
While all gathered in the Manor Garden, another issue was illustrated by Dave is the problem of invasive species. Some of you may have heard of Japanese knotweed, Giant hogweed, Himalayan balsam, Rhododendron ponticum, and New Zealand Pygmyweed. All pose a threat to the Wandle habitat, with the last on this list spreading by going with the river flow. The importance of stopping upstream by catching it in nets stops it dominating the water, blocking out light and prevent native species to grow along the downstream course.
The ride was rudely interrupted by the loud engine rasping of a stolen moped ridden by two underage kids without helmets, a reminder of the antisocial behaviour which plagues this area.
Another stop on the north bank on a footpath by the weir opposite Wilderness Island, and how does lowering a weir will drop water levels upstream. Weirs in themselves make migration of eels and other fish very difficult, one solution is a bristled matting (akin to the door mat you wipe your shoes on) to allow the eels to sliver upstream.
The ride passed through the Claudio Funari community garden and across the Hackbridge Road to a completed part of the renaturalisation of the Wandle. Gentle slopes, from the shared user path, into the water where barriers of willow and wood from the thinning out of the trees provided a twisty path of water flow. Gravel beds for spawning fish, aquatic plants taking hold too created both a visually pleasant and supportive environment for wildlife. Upstream to the white pedestrian bridge afforded better views of the tract upstream where works to reshape the habitat had been carried out.
With thanks to Dave for informing us of his work and that of the team of unpaid volunteers to make the Wandle the river it once was, the ride was at an end. I definitely recommend it and hope to join it next year.
For more information on the Wandle and the Wandle Trail follow the links below:
The ride followed this route: https://goo.gl/maps/vAmGa6wEzeZ8ACBHA