Glyn Neath Flood Alleviation Scheme

Installation of blockstone scour protection to riverbank supplemented with erosion control matting to upper faces. All works undertaken in the river used a construction platform and silt control measures.

To gain access to the river and construct the works it was necessary to work within the rear gardens of 30 properties. At the end of the project the gardens were re-instated without complaint from the owners.

Additional works included the construction of 600m of reinforced concrete floodwall to the top of the bank. The flood wall passed through the rear of 2 businesses that had to be kept open throughout the duration of the works

The excellent liaison with the residents and businesses which were kept open for the duration of the works contributed to the scheme success. The project was completed on time with defences in place before the winter. The scheme was under PAR budget.

Project Features

Glynneath Flood Alleviation Scheme.

Value Engineering

⚆ Delete soil nailing and replace with blockstone
⚆ Proposal to keep knotweed on site, reuse of excavated material

Sustainability

⚆ Excavated knotweed reused at back of flood bund
⚆ Use of recycled materials (WRAP)

Environmental

⚆ Bats
⚆ Fish rescue and liason with anglers
⚆ Construct fish wiers
⚆ Noise and dust in proximity to residents

Partnering

⚆ EA framework
⚆ Team nights out and project awards

Early Contractor Involvement

⚆ Built up PAR report which includes construction methods, VE, costs and risks
⚆ Liaised with Statutory Authorities

Risks

Archaeology

⚆ 3D scan of existing in river bridge piers prior to demolition

Whole Life Costs / Maintenance

Unusual engineering techniques

⚆ First use of soil nails as bank protection
⚆ Use of rock flailer to minimise HAV from scabbling
⚆ Use of converted 7t excavator as low duty crane
⚆ All works carried out under 33kv electric cables

Involvement of other consultants etc

⚆ liaison with WPD in relation to cables

ClientEnvironment Agency
Contact: Mrs Suzanne Bland
Tel: 029 2046 6000
ValueConstruction Award
£ 2.65m
Construction Outturn
£ 2.7m
Project Funding £ 4.5m
Project Outturn £ 4.2m
RoleEarthworks Contractor
Principal DesignerHalcrow
Tel: 029 20720920
Contact: Mrs Sally Sudworth
Principal ContractorCarillion
Tel: 01656 767673
Contact: Mr Ian Thomas
Form of ContractNEC Option C
Contract Period45 weeks
DatesMay 2006 to March 2007