Independent SuDS & Drainage Consultants • England & Wales

SuDS Drainage Strategies & Sustainable Drainage Design for Planning

Expert surface water drainage strategies, detailed SuDS design and LLFA proforma completion — tailored to your site, written to secure planning permission first time.

17+ years' drainage experience
First submission success
5–10 working day turnaround
Fixed, transparent fees
All LLFAs across England & Wales

SuDS Drainage Strategies Written to Pass First Time

Flood Risk Environmental is an independent SuDS and drainage consultancy with over 17 years' experience preparing surface water drainage strategies, sustainable drainage designs and detailed SuDS packages for planning applications across England and Wales.

We work directly with developers, architects and planning consultants to produce technically robust, LLFA-compliant drainage reports — written to satisfy the Environment Agency, Lead Local Flood Authority and Local Planning Authority requirements at first submission.

Whether you need a simple outline drainage strategy for a minor application or a full detailed SuDS design package with hydraulic modelling and condition discharge documentation, we provide a complete, end-to-end drainage service.

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SuDS RAIN GARDEN

When Do You Need a SuDS Drainage Strategy?

Most planning applications in England and Wales that involve new or altered impermeable surfaces require a surface water drainage strategy demonstrating SuDS compliance. Common triggers include:

New Residential Development

Any new dwellings or extensions creating additional impermeable area require a SuDS drainage strategy to satisfy LPA and LLFA planning conditions.

Commercial & Industrial Sites

Large roof areas, car parks and hardstanding require SuDS drainage design to restrict runoff rates and protect receiving watercourses from flood risk.

LLFA Pre-App or Drainage Condition

Where a Lead Local Flood Authority has raised surface water drainage as a pre-application concern or imposed a pre-commencement drainage condition.

Major Applications (10+ dwellings)

Major planning applications require a full SuDS drainage strategy demonstrating compliance with the NPPF, CIRIA C753 and local SuDS design standards.

Change of Use

Converting land or buildings that significantly increases impermeable coverage typically requires drainage assessment and surface water mitigation.

Discharge of Drainage Conditions

Pre-commencement or pre-occupation drainage conditions requiring detailed SuDS design, calculations and drawings to be approved before works commence.

SuDS Drainage Strategy & Design Services

From outline surface water drainage strategies for planning submission through to full detailed SuDS design packages for condition discharge — we deliver the complete drainage scope.

Surface Water Drainage Strategy

Outline and detailed SuDS drainage strategies for planning applications, demonstrating compliance with NPPF, CIRIA C753 and local SuDS standards. Covers greenfield and brownfield sites across all LLFA areas.

  • Greenfield and brownfield runoff rates (FEH22/IH124)
  • SuDS hierarchy and infiltration assessment (BRE 365)
  • Surface water attenuation sizing and outfall design
  • LLFA and LPA-ready drainage strategy reports
  • Sequential and Exception Test drainage input

Detailed SuDS Design

Full detailed sustainable drainage design for planning condition discharge, including hydraulic calculations, drainage layout drawings and construction specifications for all SuDS features.

  • Attenuation storage sizing (Flow+ v16 / MicroDrainage)
  • Design of rain gardens, swales, permeable paving & filter drains
  • Geocellular storage and attenuation tank design
  • AutoCAD drainage layout and long-section drawings
  • SuDS construction details and specifications

Drainage Condition Discharge

Complete drainage condition discharge packages to satisfy pre-commencement or pre-occupation planning conditions and secure written LLFA approval.

  • Technical response to LLFA drainage objections
  • Revised SuDS calculations, drawings and specifications
  • SuDS Maintenance & Management Plans (MMP)
  • Adoption and Section 106 drainage obligations
  • Liaison with LLFAs and highway drainage authorities

LLFA SuDS Proforma Completion

Many Lead Local Flood Authorities across England and Wales require applicants to submit a standardised SuDS proforma alongside their planning application. These technical documents must demonstrate compliance with local SuDS drainage standards — and incorrectly completed proformas are one of the most common causes of LLFA drainage objections and planning delays.

We complete LLFA SuDS proformas on your behalf, either as part of a full surface water drainage strategy or as a standalone service. Our proforma submissions are prepared to LLFA specification and cross-referenced to supporting drainage calculations.

  • All LLFA SuDS proforma formats covered across England and Wales
  • Greenfield runoff rates and attenuation volumes calculated to LLFA spec
  • SuDS hierarchy assessment and infiltration testing interpretation
  • Attenuation sizing, restricted outfall design and exceedance routing
  • Water quality treatment train and SuDS feature selection
  • Long-term maintenance and adoption responsibilities addressed
Get a Quote for Proforma Completion
LLFA SuDS PROFORMA LLFA SITE DETAILS Site Address Planning Reference Total Site Area (ha) RUNOFF RATES & VOLUMES Greenfield Qbar: 2.4 l/s 1 in 100yr Vol: 45m³ Post-dev rate: 2.4 l/s Storage req: 48m³ SuDS HIERARCHY Infiltration assessed — not feasible (clay soils) Attenuation with restricted outfall proposed Outfall to adoptable sewer confirmed MAINTENANCE & ADOPTION Responsible body for long-term maintenance FRE COMPLETED

How It Works

From your initial enquiry to a planning-ready SuDS drainage strategy in as little as five working days.

01

Free Quote

Send us your site address and planning reference. We confirm the drainage scope and provide a fixed fee within 24 hours.

02

Site & Data Review

We review site plans, topographic data, EA and LLFA requirements. We confirm whether a site visit or infiltration testing is needed.

03

Drainage Design & Report

We prepare your SuDS drainage strategy, hydraulic calculations and AutoCAD drawings — formatted for direct planning submission.

04

Revisions & LLFA Support

One round of revisions included as standard. We respond to LLFA technical drainage queries and objections where scope permits.

Trusted by Developers, Architects & Planning Consultants

We work with clients ranging from individual homeowners to national developers, delivering drainage strategies that pass first time.

★★★★★

"Antony was great to work with when we needed a Flood Risk Assessment and Emergency Flood Plan. As an architect I would definitely use FRE Consultants again — professional and produced reports within a good time frame."

Arkhi Architects
★★★★★

"The service received was great and at a competitive cost. We were granted planning after first submission."

Holly Addison — Homeowner
★★★★★

"Fast, technically thorough and understood exactly what the LLFA needed. The drainage strategy was approved without any queries. Would highly recommend for any drainage or flood risk work."

Planning Consultant — East Midlands

Need a SuDS Drainage Strategy or Detailed Design?

Get a free, no-obligation quote within 24 hours. Fixed fees, fast turnaround, all LLFAs and drainage conditions covered.

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Or contact us directly: 07826 705389  •  floodriskenvironmental@gmail.com

Flood Risk & Environmental Consulting • Independent SuDS & Drainage Strategy Consultants • Leicestershire, England

07826 705389  •  floodriskenvironmental@gmail.com

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