Yorkshire Water’s trial works to improve the quality of the river environment downstream of Swinsty reservoir is now well underway thanks to the help of a 'Spider' machine.
The company is working with partners Mott McDonald Bentley (MMB), Arup and the Environment Agency along with local landowners to assess whether river restoration techniques can help to improve the river ecology in the River Washburn.
Swinsty reservoir has been a source of drinking water for Leeds since 1878. The historic diversion of water to support the needs of local communities has resulted in the River Washburn receiving unnaturally low flows which has led to fish populations not reaching their natural numbers or species diversity.
Bioengineering specialists Salix are using their innovative ‘Spider’ machine to slow down the water and create a deeper and slower moving channel downstream of the reservoir to improve biodiversity and provide a habitat for invertebrates and fish. Trees and vegetation have also been removed to allow more light into the river and river gravel has also been rearranged, which has introduced more oxygen into the water and created new habitat features beneficial for fish and other ecology.
Jo Baxter, Yorkshire Water's Environmental Advisor, said:
“In order to judge the success of this trial we’ve already collected three years of baseline fish and macroinvertebrate data. Following the completion of the river restoration work we will repeat the ecological surveys in order to measure any changes within the river. If successful, we hope to use these techniques at other river sites across Yorkshire.”
David Holland, Technical Director for Salix, added:
“Our incredibly strong four-legged spider machine can maneuver pieces of wood weighing up to two-tonnes each into the river channel. Once positioned, they will be held securely with stainless steel cables and will maintain a good flow for fish and lead to an increase in biodiversity that will shelter in and under the wood.”
The project is part of a wider programme of work across Yorkshire over the next five years. Yorkshire Water will make improvements to 20 reservoirs and improve 100km of Yorkshire’s rivers to demonstrate its commitment to protecting and improving the environment.


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