Ditch and Heathland Restoration

Woking Borough Council

What Did We Do?

• Keystone was engaged to design a strategy for restoring the ditch and surrounding habitat that would not damage the existing heathland and would be approved by Natural England, taking into account the issues involved in working on a Nationally and Internationally Important Site.
• The improvement to the ditch was necessary to alleviate flooding issues on the adjacent highway but to ensure that it did not alter the existing hydrology of the heath.
• The work needed to be undertaken in such a way as to avoid killing or injury of common reptiles present on the edge of the working footprint.
• The banks of the ditch needed stabilisation that would last up to 5 years, would withstand cattle grazing and would either decompose naturally or could be removed by hand.

How Did We Do It?

• Negotiated use of an adjacent landowners yard for our compound and accessed the site by a bridleway to avoid impacting on existing heathland
• Surveyed the levels of the ditch and ponds at either end of the ditch followed by the production of a strategy that suggested further restoration work was required to ensure that the outcome of the scheme was successful in both protecting the heathland and alleviating the flooding issues.
• Discussed the proposed strategy on site with Natural England, followed by the production and approval of plans.
• Installed Hazel and Sweet Chestnut revetments along the length of the ditch to be restored.  The revetment was woven on site to contours agreed during a site meeting with the council ecologist.
• An ecologist worked with the operator of a light, rubber tracked machine to sort through the deposited substrate, reform the banks of the ditch in the correct soil layers, replace saved heathland turves and scrape the surface layer off to form a base suitable for heathland regeneration whilst avoiding damage to reptiles.

What were the Outcomes?

• The project was delivered to the brief and within the required timeframe.
• The site was left functional and in-keeping with the surrounding habitat.
• Keystone ensured that all the features were put in place for successful habitat recovery.
• We added value to the contract by using trees that had been removed for the creation of reptile hibernacula.  Tree root balls were left in situ but turned to face south to benefit invertebrates.