West Ewell Friday 18-March-2016
A day of habitat improvement on the Hogsmill River organised by the South East Rivers Trust. "The Hogsmill River in Surrey, England, is one of the tributaries of the River Thames. It rises in Ewell and flows into the Thames at Kingston upon Thames on the reach above Kingston road bridge. The river is 6 miles (9.9 km) in length and has a catchment area (water basin) of 73 km²" [1]
And it is a very arty river: "It was along the banks of the Hogsmill that Milais painted his famous 'Ophelia'. Hunt's painting 'The Light of the World' in which he depicts Jesus knocking at a door, was set against one of the disused huts of the Gunpowder Mills." [2]
I missed the first day due to a prior engagement. That day was spent on creating meanders to slow the flow and create whirls and eddies to scour the riverbed in places and create suitable spawning areas and also provide banks for flora to establish itself. This day was continuing that work.
The first step is to create an obstruction using a log to constrict the flow and create the basis of the meander.
The log is fixed in place with stakes.
Wires are fixed to the stakes and through grooves chainsawed across the log. Banging the stakes further in secures the log to the river bed.
Next we need some "brash" - brash wood is brittle sticks or twigs. To generate more of that Toby felled a tree and then trimmed off a load of branches.
The branches are laid in wedges both upstream and downstream of the log to create a lozenge of bank-to-be.
Using a similar technique to the main log the branches are staked, wired and tightened in place. These will eventually trap silt, be populated by plants and create a meandering river bank.
Work in progress.
Time for a well deserved lunch break - with cake.
Back into the river for meander number two.
By the end of the day we had create three meanders.
Now we let nature take its course to scour away the silt to expose the original river bed by the logs and move it along to where it can create fresh banks.
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