Ecological Due Diligence Surveys for Bank Stabilisation Works

Hydrock on behalf of Wales and West Utilities

Keystone Ecology were contracted to carry out Ecological Due Diligence Surveys in respect of proposed investigation and follow up bank stabilisation works at a gas works site. These were required to prevent the exposure of contaminants to the River Lougher in Wales.

What did we do?

• We carried out a combined River Corridor Survey and Protected Species Habitat Assessment to enable the determination of ecological impacts, guide selection of mitigation options and identify requirements for further ecological survey if required.
• Undertook a Dormouse Survey to establish presence/absence of Dormice in vegetation proposed for removal.
• Produced a Precautionary Working Method Statement (PWMS) to establish presence/absence of Dormice in trees to be felled.

How did we do it?

• We adjusted our standard Ecological Appraisal report to incorporate River Corridor instead of Phase I Habitat Survey methodology.
• Liaised closely with Hydrock contract managers to devise site investigation working methods that could progress under a PWMS prior to completion of the Dormouse Survey.
• Carried out vegetation clearance under the PWMS using Keystone Habitats, our in-house ecological contracting team who are trained to precautionary working methods for protected species including Dormice.

What were the outcomes?

• A potential delay in the start of investigation work due to the potential presence of Dormice was eliminated.
• The need to employ an Ecological Clerk of Works in addition to a vegetation clearance contractor was avoided and resulted in overall project cost savings.