Drainage Strategy / SuDS Design
What It Is
A Drainage Strategy explains how surface water and foul water will be managed on a development site. It’s a critical requirement for many planning applications, proving that the project won’t increase flood risk and complies with Local Planning Authority (LPA) and Lead Local Flood Authority (LLFA) policies. Most modern strategies include Sustainable Drainage Systems (SuDS) — such as swales, permeable paving, soakaways, and green roofs — to mimic natural drainage and meet UK standards.
Why It Matters — Risks Without It
❌ Planning refusal if drainage and flood risk aren’t addressed
⚠️ Increased risk of flooding to your site and neighbouring properties
🧾 Non-compliance with the National Planning Policy Framework (NPPF) and LLFA requirements
📣 Objections from the Environment Agency, water companies, or local residents
What’s Measured
-
Surface water run-off rates and volumes
-
Existing drainage capacity and proposed network performance
-
Infiltration rates and permeability of site soils
-
Compliance with SuDS and Building Regulations Part H
How It Works
-
Site assessment — desk study of catchments, drainage networks, and constraints
-
Ground investigation — infiltration and permeability testing (if required)
-
Hydraulic modelling — calculation of run-off rates and attenuation requirements
-
SuDS design — swales, ponds, soakaways, permeable paving, green roofs, rain gardens
-
Planning report — submission-ready Drainage Strategy report and drawings
Who It’s For
🏗️ Property developers submitting planning applications
🏢 Architects and planning consultants needing drainage input
🌍 Civil engineers requiring SuDS design compliance
🏛️ Local authorities and regulators reviewing development impact
What You Get
📄 Planning-compliant Drainage Strategy report
📊 SuDS designs aligned with CIRIA C753, NPPF, and LLFA requirements
💧 Practical, cost-effective drainage and flood risk solutions
✅ Reduced flood risk and improved sustainability credentials
Plan Smarter, Build Safer
With a robust Drainage Strategy and SuDS design, you’ll gain planning approval faster, protect your site from flooding, and demonstrate commitment to sustainable development.
