IUS – Initial Upgraded Sections
The IUS refers to the sections of the M25 between junctions 16 and 23, between junctions 27 and 30, and the A1(M) Hatfield Tunnel.
- 11,000,000 man hours worked
- 125 gantries installed
- 130,000 plants, trees and shrubs planted
The M25 major improvement scheme increased capacity of 38 miles between junctions 16 to 23 and junctions 27 to 30 by widening those sections to four running lanes in both directions.
The widening project has seen:
- more than 11 million man hours worked;
- the installation of 125 gantries including the largest single-span gantry in Europe;
- the planting of around 130,000 trees, shrubs and plants
- the relocation of more than 2,800 animals to new habitats.
The widening was completed in June 2012, in time for the London Olympic Games.
The IUS also saw the refurbishment of the Hatfield Tunnel, completed in summer 2011. The works included:
- upgrading and fully refurbishing tunnel equipment in-line with latest standards and legislation;
- full strip out and concrete repairs;
- re-equipping the tunnel with new mechanical and electrical systems including additional operational safety measures and passive fire protection;
- installation of CCTV cameras to help operators detect and clear any incidents in the tunnel quickly.