Drainage and Flood Risk Management Frequently Asked Questions
Our drainage strategy and flood risk management experts are here to address any questions you may have about your project.
What is a flood risk assessment and why is it needed?
A Flood Risk Assessment (FRA) identifies the likelihood and potential impact of flooding on a site. It’s a key requirement of the NPPF for developments in medium- or high-risk flood zones, and sometimes even in low-risk areas. At mode transport planning, we prepare robust, policy-compliant FRAs that satisfy the Environment Agency and local planning authorities, helping you move your project forward.
When should I consider drainage and flood risk in my project?
From the very start. Early assessment ensures risks are understood before land deals are finalised or designs progress too far. Identifying issues early saves costly redesigns and provides confidence when negotiating with local authorities or landowners.
What’s included in a sustainable drainage strategy (SuDS)?
A SuDS strategy sets out how surface water will be managed on-site in a safe, sustainable, and policy-compliant way. This may include infiltration systems, attenuation basins, swales, permeable paving, or green roofs. Our engineers design systems that meet technical requirements while also creating environmental and amenity benefits for your site.
How does the NPPF influence flood risk and drainage?
The NPPF requires developments to avoid areas of highest flood risk where possible, manage surface water effectively, and demonstrate resilience to climate change. Our role is to translate these policy requirements into practical, buildable solutions that support safe, sustainable development.
What adoption processes do you design for?
We prepare drainage designs for adoption under S104, S185, and related processes, ensuring that schemes are fully compliant with local water authority requirements. We also design private systems where adoption isn’t required, balancing compliance with cost-effectiveness.
Do all developments require a drainage strategy?
Yes, almost every planning application needs a drainage strategy — even small sites. The level of detail depends on the scale and location, but showing how water will be managed is essential to gaining planning approval. We’ll provide the right level of detail for your project.
What’s the difference between a Flood Risk Assessment and a Drainage Strategy?
A Flood Risk Assessment focuses on external risks, such as river, coastal, or surface water flooding and how the development can remain safe. A Drainage Strategy deals with how the development itself manages rainfall and runoff. Together, they ensure your site is resilient, compliant, and deliverable.
Do you coordinate with other consultants?
Absolutely. We work closely with architects, masterplanners, utility providers, and environmental consultants to make sure flood risk and drainage are integrated seamlessly into your overall design. This joined-up approach saves time and ensures robust, policy-compliant outcomes.
How can flood risk or drainage design unlock a site?
By demonstrating that risks can be managed and suitable drainage can be delivered, we make sites that initially seem constrained viable and attractive for development. This can significantly increase land value and reduce risk for investors.
Do you help with planning conditions?
Yes. We prepare and submit detailed drainage designs, management plans, and maintenance strategies to discharge planning conditions. This ensures your project can progress from planning consent to construction without unnecessary delays.
How do you future-proof designs against climate change?
We design drainage and flood risk solutions with climate change allowances in mind, following the latest Environment Agency guidance. This ensures developments remain safe, compliant, and resilient in the long term — protecting both your investment and future occupants.
What role does drainage play in sustainable development?
Well-designed drainage does more than manage water. It improves water quality, supports biodiversity, and enhances the public realm. Our SuDS designs create places that are attractive, resilient, and aligned with NPPF goals for sustainable growth.
Why choose mode transport planning for flood risk and drainage?
Because we combine engineering expertise with commercial awareness. Our solutions are technically robust, policy-compliant, and practical to deliver — helping you secure planning, protect your development, and add long-term value. Guided by our values of integrity, growth, passion, initiative, and fun, we make sure water management never holds your project back.
Comprehensive Services
We offer a full suite of transport planning and highway engineering and water management services, including both transport assessment, highway and associated infrastructure design, drainage engineering and flood risk management. Our team brings clarity, efficiency and technical strength to any given project at every stage from conception to implementation.
Transport Planning
We provide tailored transport planning strategies that address access, connectivity, and movement, supporting sustainable, net zero developments and new communities from “vision led” transport planning through to onsite delivery.
Highways & Infrastructure
Our teams deliver practical, efficient highway infrastructure solutions that deliver well engineered and safe road design solutions, whilst providing a clear legible gateway for all users to our client’s new development sites.
Drainage Engineering & Flood Risk Management
We develop compliant, sustainable drainage and flood risk strategies, designed to ensure that surface water is managed sustainably and efficiently and that our solutions integrate seamlessly with our client’s development plans, site requirements and Environmental Agency guidance.
Speak to An Expert
Looking for support with your next project? Get in touch with our experienced consultants for a free, no-obligation conversation.