M62 Bridge Deck Drainage
Upgrading bridge drainage
Location: M62 Interchange, West Yorkshire
Service: Bridge Deck Drainage Design and Compliance
Scope: CG501 and BS EN 1433 Compliant Drainage Design
Overview
Courous Ltd was engaged to develop a robust drainage design for the M62 Interchange parapet upgrades. The works were required to ensure compliance with DMRB CG501, CD 533, and BS EN 1433, and to address runoff management from the bridge deck, all while coordinating around numerous existing underground utilities and traffic constraints.
Challenge
The existing system was not fit for purpose, with limited hydraulic capacity and risk of sediment build-up under low-flow conditions. The scheme also had to accommodate strict structural and safety requirements due to proximity to parapets, statutory undertaker services, and limited working space on the bridge deck.
Our Solution
Our design included:
A fully compliant combined kerb and drainage (CKD) system using ACO KerbDrain units
Bridge deck catchment design using the Wallingford Procedure to model hydraulic capacity
Installation of access and outlet units, with 225mm and 150mm outlet pipes, tailored to specific flow demands
Ensuring watertight flexible joints in line with Clause 504 and CCTV validation under CS 551
Coordinated protection of Statutory Undertaker services and environmental safeguarding during trenching and reinstatement
All units were selected for compatibility with parapet edge clearance and kerb profile requirements (75mm upstand, 45° splay), with sediment-resistant channel profiles.
Outcome
The new drainage system is capable of handling peak flow rates (up to 25.23 l/s per CKD run), supports bridge deck safety, and was designed to meet all maintenance, access, and testing standards under the MCHW and DMRB guidance.
Conclusion
This project demonstrates Courous Ltd’s ability to deliver complex drainage solutions for strategic highway structures, ensuring long-term performance, resilience, and compliance with national standards.