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Porter Brook - Channel Habitat Improvement in De-Culverted City Centre Stream

There will be more pictures and video to come to document this bold project by Sheffield City Council to uncover a section of stream that used to live beneath a factory floor. They are in the process of creating a "pocket park" that will provide new flood-water storage (when the rivers are in spate) and an improved public park amenity (when the rivers are calm).

The pocket park itself will be excavated out from the current high ground level (and a major construction project is underway at the moment to achieve this).

The Wild Trout Trust were brought in to design in-channel features and riverbed morphology that would maxmise the improvements for the ecology of the stream - including for the prospects of a small and fragmented native population of wild brown trout.

The site after uncovering the stream - but before the in-channel works

Part way through the Pocket Park Construction - new gabion walls and flood defenses

Channel with boulder clusters, log deflector-consolidated point-bars, pool, riffle and meanders plus pre-planted coir pallets and rolls installed by Wharton Landscaping Ltd. on top of berms that were created by redistribution of bed material under WTT direction

Boulder Cluster: for cover against predation, baffling of spate flows, creation of depth variation and substrate retention

Ian from Whartons models the size of rebar pins I used to secure the log deflector(pictured) that is helping to retain the shape of the point-bar made from channel substrate

The head of a 2-m long rebar pin (towards the right) driven into the bed for its full length. To the left is a cut-off end of a pin that was driven half-way before hitting something impenetrable. Bending it over and cutting off provides additional anchoring to each of the main pins when this happens

Boulder Cluster pictured previously (top right of frame) plus log deflector/point bar also pictured previously (top middle of frame) creating and preserving meandering flows into the upstream end of the shaped and planted berms. Big boulders against the wall are helping to protect the upstream end of the berm as well as maintaining meandering flow. Note also the large submerged boulder providing habitat and breaking up flow patterns to produce refuge areas (left of centre frame)

Planted berms on right and left of channel. Narrowed pinch point will promote and retain greater depth of water (offering better protection against low flows during dry summers compared to previous uniformly flat/shallow reach)

Pocket water created by addition of scattered boulders between two planted berms (natural gritstone excavated on site and broken into irregular chunks)

Pocket water detail (facing downstream)

Third planted berm - left of frame (pictured facing downstream)

There is now a great deal more structural variety in the channel. This is true in terms of flow speed and depth and well as in physical structural components (including overhead cover on the undersides of "rock rolls", undersides of boulders and, in future, emergent vegetation). I await the development of this project (including the completion of the pocket park itself) with interest. If the rock-rolls prove to be a great success in protecting the planted coir components - then these might give more town and city councils confidence to try these kind of measures in a wider range of urban streams.

I will post more photos and video on this project as soon as I am able to...


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Catching and Releasing the first Fly-Caught wild trout from a stream that was dug out of a city-centre pipe was probably the highlight of 2016 for me!

Buried in a brick tunnel under England's industrial developments of the 1800s, a section of the Porter Brook in Sheffield was brought back to the surface by a bold project co-ordinated by Sheffield City Council and involving the Wild Trout Trust, The Environment Agency and many more partners.

You can now witness the actual process of freeing the Brook from its pipe - and the creation of functioning trout-stream habitat in this short video.

Yet, the above video does not show the completed park that was a huge part of the entire project - and it does not show the planted vegetation beginning to develop in the summer of 2016. And, it does not show any fly fishing or video of a trout capture...

But the film, below, that was made by the excellent Huckleberry Films as part of the Canal & Rivers Trust "Living Waterways" awar…

Buried Stream Project Wins National Prize

I'm delighted to say that the Porter Brook Deculverting project was selected as the 2016 Winner in the Canal & Rivers Trust for "Contribution to the Built Environment". This was a multi-partner partnership project (with key involvement of Sheffield City Council, the Environment Agency and more) that I was fortunate to have the opportunity to design the in-channel habitat features to provide the best functional benefits for trout and the wider aquatic foodweb. The Sheffield Branch of Trout in the Town "SPRITE" are caring for the habitat as well as monitoring the aquatic life in this new section of daylighted urban stream.

As well as my previous blog posts on the subject, the awards scheme made short videos (less than 2-minutes) long that captured key elements of each project entry. You can see the film for the winning Porter Brook project below. Please enjoy and share (and also check out the other project videos on YouTube from this year's awards).

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 …