Loadpit Beck gets some Love

John Franklin, our Better Becks Officer, has been working in Loadpit Beck facilitating the weir removal there.

What was the problem?

During walkovers as part of phase 1 of the ‘Better Becks’ Project, dozens of barriers to fish passage were identified within tributaries of the Middle Aire Catchment. On Loadpit Beck, a concrete ‘apron’ spanning the whole channel width was found. Installed as a reasonably over-engineered scour protection structure for the adjacent surface water outfall, this ‘apron’ has been stopping fish from progressing upstream to access good quality riparian habitat. The barrier was doing this in two ways, by creating an artificial drop in height in the channel, which many fish are unable to swim up, and by creating conditions for thin, laminar flow (like a sheet), which is challenging to swim up, as the water speed is increased, with little opportunities for rest.

Phase 2 of the Better Becks project is all about addressing the problems found. The Fisheries Improvement Program, where funds are raised from angler’s rod licenses, was a great opportunity to cover the cost of this removal, as improving fish passage in Loadpit Beck would also help support fish populations in the fishable waters of the River Aire, 400m downstream.

…and the solution?

The works themselves, with permissions and support from Bradford Council and local landowners, were undertaken in August 2024 with Prof. Jonny Grey of the Wild Trout Trust being brought in as the principal contractor, alongside operational support from Ian and Pat from Atkinson Surfacing. Using handheld machinery, a new channel was cut into the right-hand half of the concrete apron. This was to enable retention of the scour-protecting function of the apron on the left side of the channel, below the outfall. Rather than cutting down to the channel bed, the material was cut away to retain a naturalistic channel within the concrete, to ensure fish passage, whilst also avoiding the risk of the channel scouring out in future. Sediment management was used downstream of the works to minimise fine concrete dust and silt mobilisation becoming an issue for aquatic organisms below the works.

As soon as the concrete breaker was lifted out of the water and the generator turned off, we all watched a Bullhead fish making the first journey up and above the barrier, enjoying the restful riffles of the new passable channel.

Monitoring the impact

Downstream of Loadpit Beck ART Volunteer Carolyn Robinson, who monitors river flies, says:

‘Riverfly Monitoring is a Citizen Science project that enables volunteers to gather information about the water quality of the River Aire and its tributaries. Following training and assessment, I was paired with another volunteer and together we monitored a site on Loadpit Beck that runs through Trench Meadows.

Once a month we ‘kick sample’ the site wearing wellies and using a standard net for 3 minutes, then check under large stones for 1 minute, ensuring comparable samples are taken over time. The sample is rinsed to remove unwanted debris, poured into a large tray and examined. We are looking for eight pollution-sensitive species of invertebrates that should be present in a healthy river. They are then transferred to an 8-segmented tray for counting, where we looking for 2 types of caddis flies, 4 types of up-wing flies, stoneflies, and freshwater shrimp. We also note the presence of other insects, snails or fish in the sample as well as any creatures that survive in polluted water eg leeches.

The number of each species is counted and allocated a score e.g. 1-9=1 point, 10-99=2 points, 100-999=3 points. At Trench Meadows our score has been between 8 and 14 points, we have identified all 8 target species, but not all on the same occasion. We are allocated a Trigger Level, and if our score falls below this there has possibly been a pollution event. We will check upstream of the site to look for any obvious pollution, changes in water colour etc and re-sample. If pollution is found or the score is still below the Trigger Level, the coordinator and local ecology contact are informed. Thankfully that has not happened at Trench Meadows, and it continues to be a healthy site.’

River Worth Weir Walkers

Ellie’s Weir…ed Blog

In this post our GIS whizz Ellie Spilsbury outlines some of the work we have been doing to identify ways to improve the sustainability of the fisheries in our rivers and hopefully aid the return of salmon for the first time since the Industrial Revolution.

*Look closely and you will see hundreds of Minnows collecting at the bottom of this weir, unable to ascend. See the area in the water that looks dark brown; they are Minnows.*

Visit each of the three sections for more detail:

A familiar Story

Data analysis with a Salmon Splash of professional opinion

(Tr)outcomes expected

A familar story

Once upon a time, our River Aire had the highest Salmon population of any Yorkshire river. Then came the Industrial Revolution, which saw the wool and fabric industry boom throughout Yorkshire. Mills were constructed accompanied by weirs to harness our river’s energy. Although the mills are now closed and are becoming swanky new flats, the weirs often remain, isolating ecosystems that lie between them. Weirs disrupt the natural transport of sediment downstream, causing a build-up of silt and gravel behind the weir, which is detrimental to the habitat of spawning fish. Since 2011, one of the Aire River Trust’s goals has been to increase the connectivity of our river and its tributaries by removing or re-configuring weirs to allow fish passage. Following earlier work to install fish passes through and downstream of Leeds, significant steps towards this goal were made in 2022 with the successful construction of four fish passes as part of the DNAire project.

When we see water flowing over weirs, creating the sounds of waterfalls and visually pleasing white waters, it is easy to forget their man-made heritage and artificiality. It is hard to imagine seeing through the eyes of a migrating trout or salmon; every cell in its body instinctively directing it upstream to spawn, using both the stars and the earth’s magnetic field for navigation and then facing an unpassable wall of Yorkshire-dressed stone. It is often not just the height of the weir that presents the issue but the combination of weir height and the shallow depth of the concrete sill below the weir. The height at which salmon and trout jump is directly affected by the relative depth of the water at the foot of the barrier and the “hydraulic jump,” which boosts their leap.

The Environment Agency (EA) has identified around four hundred river obstacles within the Aire Catchment. However, we believe there to be many more. For example, the EA recorded two barriers to fish passage on Pitty Beck, yet on our Bradford Becks Walkovers, we found 11. This pattern is most likely repeated on each beck. Currently, tackling the removal of every weir in the catchment is unattainable. So, how did we prioritise them into a workable top twenty?

Data analysis with a Salmon splash of professional opinion

With help from The Rivers Trust, we are the first regional rivers trust to code an ArcGIS tool to accurately calculate the length of a river (including tributaries and forks) that would be opened and re-connected by the removal of every mapped weir in the Aire Catchment. Alongside this, we analysed ecological assessment data, invertebrate biodiversity, local community data (including deprivation), and weir visibility to the public. We assigned a score to each outcome and designed a weighted decision-making matrix that identified the weirs that scored the most highly. The data only tells us half the story, so we took our results to our expert team and discussed those weirs for which a solution in the short(ish) term might be feasible.

Once we had twenty feasible weirs, it was time to ground truth our ideas. The purpose of site visits is to add or, more often, diminish our confidence in the feasibility of the weir so that we only carry the most achievable sites to the next stage. We evaluated the weirs’ condition, site access, utility services or abstraction points, and landowner engagement by photographing and recording the area, our thoughts, and encounters.

The most surprising discovery for me was the actual size of a weir. After months of viewing photographs without visual perspective, weirs can appear to be half the scale of the real-life structure. Take a moment to analyse this photo: how tall do you believe it to be? See the very bottom of the blog for the upside-down answer.

(Tr)outcomes

We are fast approaching the end of the site visits and write-up stage. It is time to narrow our shortlist of twenty weirs down to four. So, it will be back around the table for our professionals to decide on the four “leak” proof projects to invest in. These four weirs will be subject to a comprehensive feasibility study and design process. I hope my next blog post will include more designs, machinery, hard hats and re-naturalised rivers.

River Worth Improvement Plan

Weir today. Gone tomorrow?

A group of postgraduate students from the University of Leeds have been visiting the riverside in Keighley as part of their “Engaging the Modern City” module. They’ve been keen to find out more about the river and what residents want to know about it. In response, they’ve produced the leaflet below.

On the front we will use several modules to present the issues we have investigated and a module at the back to recommend areas of PR activity around Keighley and to summarise our fieldwork
Jingzhe Zeng

A central theme they have been particularly interested in is the old weirs. What was their purpose? What do people hope might happen to them? Should they remain?

There used to be dozens of mills that thrived on the River aire, but now these mills have mostly been transformed into heritage for other activities.

The concern, however, is that the weirs that provided power to these mills still remain as part of the river channel, and from an ecological standpoint, they block the passage of fish that want to swim upstream for food, breeding, or refuge.

The ideal solution would be to remove these structures to make the river more level, or to build fish passes. For more details, check out https://aireriverstrust.org.uk/fish-passes/.

Please feel free to share your thoughts in the comments. Do you support the removal of weirs? Why or why not?
Jingzhe Zeng

Two fish leap in a graphic that divides text

Reconnecting the river for wildlife

The Aire Rivers Trust has just completed it’s Developing the Natural Aire project. Together with the Environment Agency, we have built fish passes to link 40km of the river to encourage the return of Atlantic salmon.

“It is fantastic to know that these fish passes in the upper River Aire are working as designed, and important fish species are rediscovering their key habitat

“As well as reopening rivers to fish migration and protecting ecologically important and endangered species like salmon and eel, fish passes are an amazing opportunity to reconnect river-resident species and the local community.

“Over the coming years, we look forward to seeing a growing proportion of trout, chub, barbel and salmon run spawning journeys higher up the river and a recovery in their populations.”
Thomas Somerville, Environment Agency’s Developing the Natural Aire Project Manager

Weir Walkers