Hello Matt here again. I just wanted to tell everyone about our Moss Valley Project which has finished after starting it in December 2017. This project has been funded by Yorkshire Water and Don Network grants.
We worked with landowners, parish councillors and the Moss Valley Wildlife Group to establish aims for the project through a number of designated tasks.
Our aims for the project were to remove an obstacle to fish migration, improve instream and riparian habitat, reinstate flow to Never Fear Dam and to remove encroaching scrub from a nearby fen thereby improving the ecological condition of the Moss catchment.
Remove obstacle to fish migration
The collapse of Neverfear Weir several years ago presented an opportunity to remove this obstacle to fish passage on the Moss Brook. During high flows the weir had breached, but the debris still presented a barrier to fish movement (see Picture 1). Through a combination of manual clearance (see Picture 3) and the employment of a digger and drill we were able to clear the debris blocking the river (see Picture 4).
Picture 1. Neverfear Weir blocking the Moss Brook
Picture 2. Digger breaking capstone apart
Picture 3. The team at work clearing debris.
Picture 4. Connectivity restored.
Improving instream and riparian habitat
In-stream habitat was improved in over-widened channels through the installation of fixed woody debris (see Picture 5) and the creation of ‘tree kickers’ (see Picture 6) which improved natural processes such as sediment sorting, scour, flow heterogeneity, as well as introduced new microhabitats. The riparian canopy was thinned, as a mixture of tree cover and canopy improves biodiversity.
Picture 5. The Wild Trout Trust demonstrating how to use fixed woody debris to improve river habitat.
Picture 6. Some of the ‘tree kickers’ habitat enhancement work.
Picture 7. This fixed woody debris was placed at a point of excessive erosion so to reduce the amount of sediment entering the river in addition to providing new microhabitats.
Removal of scrub encroachment
The riparian fen at the bottom of the Moss Valley SSSI was becoming increasingly overrun with trees and scrub (see Picture 8). Over nine days we worked with volunteers to clear small trees, scrub, brambles and Himalayan Balsam (see Pictures 8, 9 & 10).
Picture 8. Trees and scrub encroaching on one of the fields.
Picture 9. The same field after clearance.
Picture 10. No cutting had been done for a number of years so trees of substantial size needed felling.
Reinstate Flow to Never Fear Dam
A goit leading to Never Fear Dam had kept the dam topped up with water. But over time the bank wall had eroded away allowing water escape back into the main river (picture 11) leading to water levels dropping in the dam.
Picture 11. Water loss from the goit (before)
We rebuilt the goit bank using stone from the concrete capstone and used the digger to deposit clay and soils to reinforce the bank walls. To prevent erosion we secured coir netting to the soil and spread grass seed to knit the soil together (Picture 12.).
Picture 12. Goit wall (after)
Another issue occurred during high water/winter conditions with a lot of water pooling around bridge over the goit (picture 13). This was due to a culvert being silted up reducing the flow. We decided to remove the culvert and replace it with a bridge (picture 15) allowing free flow of water underneath.
Picture 13. Silted culvert (before)
Picture 14. New bridge over Never Fear Dam goit
We created a spill way (picture 15) upstream of the bridge to allow water to be released back into the main river, relieving the amount of water passing further down.
Picture 15. Spill way
The last job: Introducing marginal plants to Neverfear Dam
Now that water levels in Neverfear Dam have been restored we finished off our Moss Valley Project by introducing a mixture of marginal plant species to Neverfear Dam during a volunteer day. (Picture 16, 17 and 18) This included Yellow Flag Iris and Phalaris grasses, which have been known by the MVWG to have once grown in the area providing habitat for harvest mice.
Picture 16. Before
Picture 17. During
Picture 18. After
Thank you to everyone that has been involved with the Moss Project over this last year, couldn’t have done it without our dedicated volunteers.