West Anglia Main Line Capacity Improvement Scheme

Robin Slade

Robin Slade

Regional Director

Tel: 01483 310600


Volker Fitzpatrick on behalf of Network Rail



  • Earthworks Strategy
  • Materials Management Plan
  • Remediation Method Statement
  • Design of Contamination Protection Measures
  • Liaison with Regulatory Authorities
  • Monitoring and Verification of Works

Earthworks and remediation strategies for new station and widened track

Volker Fitzpatrick (VF) engaged CGL to develop an earthworks strategy as part of Network Rail’s £170 million Lee Valley Rail programme, which has provided a third track, with passive provision for a fourth, on 5.5km of the West Anglia Main Line between Lea Bridge and Angel Road stations in north London.

The programme will reduce congestion on the line and enable an additional two trains per hour on the route. It also includes construction of the new Meridian Water station, adjacent to the former gasworks in Edmonton, with additional platforms at Northumberland Park and Tottenham Hale stations. The new station will serve Enfield Council’s planned £6bn Meridian Water Housing scheme, which is set to deliver 10,000 new homes.

CGL’s earthworks strategy was divided into two parts to separate the new track bed works from the new station. CGL developed the strategy including a materials management plan to manage the surplus material resulting from the widened track bed area. CGL undertook risk assessment of track bed data enabling materials to be used on nearby Network Rail land, reducing costs and environmental impact of offsite disposal.

The former adjacent gasworks site was impacted with significant contamination, including hydrocarbons and ammonia, which were present beneath the station site and CGL produced a remediation method statement (RMS), including the design of protection measures, to address the contamination risk and enable construction of the new station and associated facilities. The measures included installation of hydrocarbon and vapour resistant membranes and design of below ground drainage to avoid creation of preferential pathways for migration of mobile contamination towards the local Pymmes Brook. CGL engaged with the Environment Agency (EA) to address the EA’s comments on the strategy, assisting with sign off.

CGL’s RMS included ongoing monitoring measures to check groundwater quality associated with the station construction and CGL is now providing monitoring and verification services on behalf of the client.

CGL’s involvement enabled the client to meet its planning and regulatory requirements and helped make financial savings by maximising reuse of site won materials.