Project overview 

Effective management of road runoff is essential for protecting water quality, reducing flood risk, and improving the resilience of the highways network. Poorly managed runoff can harm aquatic ecosystems, contaminate water sources, damage infrastructure, and impose significant costs on communities, local authorities, and the wider economy. As climate change brings more intense and frequent rainfall, addressing road runoff has become an increasingly urgent priority.

However, much of the existing highways network was designed at a time when water quality and climate resilience were not key considerations. Ageing drainage systems, constrained budgets, fragmented responsibilities, and challenges associated with maintenance and coordination mean that runoff is often discharged untreated into the environment. As a result, opportunities to deliver wider environmental, social, and placemaking benefits through highways works are frequently missed.

This CIHT project explores how highways maintenance can be repositioned as an opportunity rather than a barrier to effective road runoff management, focusing particularly on:

• The challenges preventing the successful implementation and long-term maintenance of road runoff management measures.
• Practical recommendations to help local authorities integrate runoff management into routine highways maintenance, urban regeneration, active travel schemes, and wider infrastructure projects.

Access the policy brief

Please complete and submit the form to access the report. 

About the policy brief 

How has this policy brief been developed? 

This report has been developed with the support of the CIHT Partnership Network, the CIHT Technical Champions and experts in the sector. 

Insight has been gained through a workshop, held in November 2025 and a literature review.

What's in the policy brief?

• Key facts and figures about the scale of road runoff in the UK.
• An overview of the different solutions available to manage road runoff, and their associated limitations.
• The case for using highways maintenance as an opportunity to build new and maintain existing solutions.
• UK and international case studies, exploring how this approach works in reality. 

Key takeaways

• Growing challenge: Road runoff carries pollutants into watercourses, affecting water quality, ecosystems and increasing flood risk.​
• Effective solutions: SuDS, nature-based solutions and traditional drainage measures can reduce pollution and manage surface water.​
• Wider benefits: These measures can support biodiversity, habitat connectivity, urban cooling and better public spaces.​
• Maintenance matters: Regular inspection and maintenance are essential, but funding, disruption and coordination can be barriers.​
• Opportunity: Integrating runoff management into highways maintenance, regeneration and active travel schemes can reduce costs and deliver wider resilience and placemaking benefits.

More information 

For any questions about the report please email technical@ciht.org.uk