Skip to main content

Colne Grafting

As many of you know already, the inspiration for the WTT to seek funding to set up the national Trout in the Town project came from Andy Pritchard's band of folk on the River Colne in East Lancashire. Watch and enjoy the video below, filmed and edited by Colne's Albert Wood. Check out guest appearances of "Sheffield Trout in the Town" luminaries Kath and John Blewitt. The brash that was being collected was destined for pulping following tree works at a plantation at Stocks Reservoir. Just a few simple phonecalls and emails (via Natural England) identified this source of "soft revetment" raw material. A couple more emails to let Andy P know of the opportunity and the next thing you know he's dashed off a risk assessment and arranged a fleet of flatbed tipper vans and trailers along with a band of volunteers to shift the lot 15 miles to Colne. Andy and all the rest of the folk are, I'm sure you'll agree, an inspiration for the amount of sheer hard work they are willing to organise and complete during their "free" time.

The resultant 8 tipper loads of brash will be used to slow down the rate of inappropriate erosion that is currently exposing service pipes and putting too much sediment into the river Colne just upstream of the main town (an example of similar work on the river Manifold can be seen in the photos at the bottom of the page).

When banks are being lost at a rate of around one metre per storm event along miles of riverbank (like here on the river Manifold), terrestrial and aquatic flora and fauna are badly impacted

Brashings can be used to slow down runaway erosion and collapse of riverbanks

It is important to highlight that erosion is a vital ecological process - but can run out of control in grazed systems. In such instances, extensive regular bank loss leads to significant reductions in habitat quality for a wide range of aquatic and terrestrial species of flora and fauna. Attempts to stop erosion dead in its tracks using "Hard" revetments of blocks of stone or gabion baskets often create more problems than they solve (due to eddying currents arising from their relatively smooth, geometrically angular surfaces). Fast linear flow and whirling vortices that are both promoted by "hard" engineering result in flashier river flows and higher potential for destructive erosion. Brashings are an ideal alternative due to their very high surface area to volume ratio (hydrologically, they are much "rougher" than hard engineering). This has the effect of "stilling" or damping out fast flowing water currents next to the bank, accumulating sediment, regrading the vertical bank faces to a more shallow incline and (in combination with managed livestock access) allowing marginal vegetation to grow up and consolidate the new bank. The branches also provide habitat in their own right for a range of invertebrate and vertebrate species (including juvenile trout and kingfishers as notable, linked, examples).


Nick Moody said…
Wahl, that's great, thanks Paul.

I've read down your whole blog to here, so far, and this article taught me something new.

I've already copy and paste - forwarded the ones above about Weir removal and the diagram for stream improvement with an upstream V etc to my father who is restoring his own section of a spawning stream near Christchurch, in South Island, New Zealand.

It's great to see how professional, and further developed urban and small stream restoration is in the UK. As here in NZ we are lagging far behind.

I think that some of my fellow 'Community based stream restoration' fans and practitioners should attend some talks and training with your organisation!

Nick Moody

Queenstown, NZ.

( )

Popular posts from this blog

First Survey Record of Wild Trout Returning to Lyme Brook Habitat Works Site!

You may have seen the first three phases of works on the middle reaches of the Lyme Brook (shown in previous blogs Here and Here) from project works that began in 2015...

Well although the first surveys after that work found some nice coarse fish populations - there was no cold hard evidence that any trout had found the newly-improved habitat...Until now!
I received a phone call today from Matt Lawrence who is the EA's Catchment Host for the Trent Valley Catchment Partnership (with key partners Groundwork West Midlands and the Wild Trout Trust who conceived and delivered the habitat works). Matt told me that he'd had some exciting preliminary reports from a EA Midlands fisheries surveys team. Their survey on 7th September had caught several wild trout as part of their sample on the habitat works site.
These are the first modern records of trout in the brook and is also the exciting news that we have been waiting for on these first phases of work to create spawning, juvenile an…

How Volunteers in Sheffield Make Big River Habitat Projects Successful

You've done a big, ambitious partnership project to deculvert a section of urban stream, but now the civil engineering contractors have gone to their next job. The site is left to mature...what next? Very seldom does this kind of project have any budget for ongoing ecological monitoring (which is a frequent and justified criticism of habitat improvement works - the lack of ecological effect data).

The same can be said for general "husbandry" of the site - whether it be litter or invasive plant control; or even fairly substantial running repairs...

Step in SPRITE (Sheffield Partnership for Rivers in Town Environments) whose site you can check out on, the Sheffield Trout in the Town group and a supporting donation of pre-established planted coir products from Salix River and Wetland Ltd. (with their site here:

You can see SPRITE talking about their aquatic invertebrate monitoring and see their repair and site care wo…

A previously buried section of stream produces the first fly caught trout in >160 years

As near as I can work out from the archaeology report, this section of river - recently brought back to the surface in dramatic fashion by Sheffield City Council, the EA and the WTT partnership - was buried in a low brick tunnel somewhere around 1853 to 1868. The northern half of the site was certainly buried underground BEFORE the time the 1853 map was produced....and the rest of the brick tunnel was placed over the top of the stream before the map of 1868...

Of course, it is not easy to tell what the water quality was like in that section even BEFORE the stream was buried...and whether there were trout surviving in the stream when it was sealed underground...

What is damned sure is that you couldn't wave a fly fishing rod around in that underground tunnel once they'd built it!

This was still the case until the completion of the massive project to remove the brickwork and create an attractive "pocket park" in the city centre. You might have seen from This Previous …