After months of planning and preparation the weir removal and river restoration project at Hackbridge is finally underway!
Those of you who have crossed the road bridge over the river or walked along the Wandle Trail in the past few weeks will have seen big changes with heavy machinery in the river, the sound of breaking concrete and the sight of a river re-emerging.
Our skilled contractors Cain Bioengineering with site manager Nick and his team of Alex and Jimmy have been working hard to bring to reality our vision for the river.
Gravel, stakes and hazel faggot bundles at the ready in the compound:
The work started with the removal of the heavily creosoted toeboarding from around the edge of the island.
Toeboarding removed from the island and an old speaker found in the river!:
The toeboarding still smelt strongly of creosote after many years in the riverbank:
A new island bank line was then created with hazel faggot bundles secured with chestnut stakes and backed with coir netting in order to extend the island and narrow the river. Sediment from the channel (of which there was a lot!) was then placed behind the new bank line. This sediment is a result of the weirs slowing the water flow and causing sediment particles to settle out and smother the natural gravel bed.
Scraping sediment to place behind the new bank line:
After the creation of a new bank line parts of the island were regraded to create a gradually sloped bank that will be planted up at a later date with plants suitable for the different habitat zones created. The dead trees were retained as they are an important habitat for all sorts of creatures including bats, woodpeckers and invertebrates.
Regrading the island with the excavator:
With the bed nearest the weir cleared of much of the sediment the weirs were breached and the process of breaking up the old weir structures begun. The weir was found to be made up of cast iron plates, concrete, brick and lumps of chalk. The cast iron was recycled and the proceeds will be converted into a pair of waders for our volunteer events!
Smashing up the old weir:
Once the weirs were breached the water levels dropped upstream and the process of narrowing the channel was started with a combination of more posts and faggot bundles or stone.
Forming a new bank line to narrow the river:
A sinuous meandering channel is starting to take shape and will allow for a variety of depths and flows with deeper faster flowing outside bends and shallower slower flowing inside bends providing varied habitats.
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Starting to take shape:
There have been many practical challenges along the way with sewer pipes, water mains and electricity cables criss crossing the river to be identified and avoided. The joys of urban river restoration projects!
Locating an electricity cable:
Look out for more updates as the work takes shape over the next week!
We will be holding a number of planting events to plant the island with native plant species in early September so please get in touch if you are interested in getting involved.
Really great to see this project under way. Will make a tremendous difference to this part of Culvers island. John
The view of the Wandle from Hackbridge bridge was about the only piece of beauty left for us to enjoy. It was natural and supported an abundance of wildlife. God how horrible it now looks and a complete absence of ducks etc indicates they share my horror. Will that view ever be returned for us and its former wildlife to enjoy. I’ve a horrble feeling that was the last piece of rural Hackbridge to bite the dust. RIP
Chris, we’re sorry to hear of your horror at the appearance of our work in progress at Hackbridge, but please rest assured that it won’t look like a building site for long.
A beautiful, natural gravelly chalkstream has already been recreated where a system of (highly unnatural) weirs has been strangling the river with a deep pan of really nasty silt for at least the last 50 years. Within a few months the native vegetation we’ve planted along the river’s new, clean gravels will have established, providing ducks, moorhens, kingfishers, herons and all sorts of other birds (as well as fish, insects and hopefully even water voles) with much better habitat.
We can promise you’ll see far more wildlife around this new, healthier stretch of river in the future. And we know this isn’t a rash promise, because we’ve already done it very successfully on a smaller scale, just above the railway bridge in Carshalton – do have a look at this area from the Millpond Place bridge if you haven’t seen it yet!
For years children have fed the ducks near the bridge at Hackbridge including my own but since the alterations to this part of the river the mallards have all been chased away by 2 much larger ducks (species unknown). Whilst walking my dog the other day 2 of the mallards dared to venture in this part of the river. They had a duckling with them and they were viciously chased by the bigger ducks and forced under the bridge and subsequently became separated from the duckling. The duckling was very distressed and eventually the parents tried to return and were looking everywhere for the duckling and also getting distressed. At this point I had to go but obviously the new environment is just right for the bigger species which have claimed it as their own territory. I know this is nature but the whole nature of this area that used to be enjoyed by children fishing with nets and feeding the ducks has changed and I think this is very sad.