Soham Lode Re-visited

An important water vole site at Soham Lode required emergency re-lining of the perched section of the reach (approximately 600m). Following the emergency works, Salix were awarded a Design & Build contract on a competitive bid process to reinstate the marginal vegetation and green up the embankments.

The liner prevented stakes being used and created a slippery surface for soil placement. Therefore, a woven loop geotextile was used over the liner in order for Coir Rolls and brushwood faggots to be tied onto the loops.

The brushwood faggots created a physical barrier preventing the soil fill placed on the banks slipping down the slope. A total of 1200m of pre-established Coir Rolls was placed along the toe of each side of the re-lined section to form dense marginal planting.

An Environment Agency report carried out after the works concluded:

The marginal vegetation has flourished during the spring/summer months and has created a functional corridor for many species. Following a “spot-check” on the 11th August 2011, FRB can confirm that water voles have also returned to the re-lined section: both droppings, including a latrine, and feeding signs were recorded.

This is an excellent result as the Coir Rolls were only installed in March 2011 and are already providing suitable habitat for the water voles.

FRB will undertake a water vole survey of the complete stretch in September 2011 to determine whether the entire 600m is being utilised by water voles, a priority Biodiversity Action Plan (BAP) species. These works will also contribute towards WFD objectives.