Flood Risk & Drainage Consultancy Pricing
Fixed, transparent fees for all services. Free no-obligation quotes within 24 hours. No hidden costs, no surprises.
How Much Does a Flood Risk Assessment Cost?
A Flood Risk Assessment costs from £295 for a simple Flood Zone 1 site, £485–£695 for most changes of use and extensions in Flood Zone 2, and £750–£995 for higher-risk Flood Zone 3 or tidal sites. A combined FRA and surface water drainage strategy starts from £1,349. Every fee is fixed and quoted within 24 hours, with no VAT to add — which makes our prices roughly 20% lower than a VAT-registered consultancy quoting the same figure.| Report | Fixed fee | Typical turnaround |
|---|---|---|
| Flood Zone 1 FRA (simple statement) | from £295 | 5–10 days |
| Instant automated flood & environmental screening (The Property Search) | £20 | instant PDF |
| Pre-purchase Flood Risk Report (desk-based) | from £350 | 2–3 days |
| Change of Use FRA (Flood Zone 2) | from £485 | 5–10 days |
| Householder Extension FRA | from £695 | 5–10 days |
| Garden Room / Outbuilding FRA | from £650 | 5–10 days |
| Higher-Risk / Tidal FRA (Flood Zone 3) | from £750 | 5–7 days |
| Office-to-Residential / London FRA | from £995 | 5–7 days |
| FRA + Drainage Strategy (combined) | from £1,349 | 5–10 days |
| Surface Water Drainage Strategy | from £995 | 5–7 days |
| Detailed SuDS / Drainage Design | from £1,499 | 7–10 days |
| Sequential & Exception Test | from £395 | 5–10 days |
| Flood Warning & Evacuation Plan | from £350 | 5–10 days |
| Drainage Condition Discharge (design, calcs, drawings, maintenance plan) | from £1,849 | 10–15 days |
| Flood Condition Discharge / Resilience Statement | from £595 | 5–10 days |
| Flood Consequence Assessment (Wales, TAN 15) | from £895 | 10–15 days |
| BRE 365 Soakaway Testing (add-on) | £2,420 | subject to access |
| Construction Phase Flood Management Plan | from £1,950 | 10–15 days |
| Independent Flood Investigation (councils, LLFAs, property disputes) | Priced on scope | agreed on instruction |
Our Pricing
We believe in transparent pricing. Most flood risk and drainage consultants won't publish their fees — we do, because we think clients deserve to know what to expect before committing.
All prices below are fixed fees with no VAT to add — the price we quote is the price you pay — and are indicative starting points.
Standard vs Rapid: prices shown are our Standard service, with most reports delivered in 5–10 working days. A Rapid service for urgent applications is available on request (typically +£200). Every fee is fixed and confirmed in writing within 24 hours before any work starts.
Free quote within 24 hours. Send us your site address, planning reference and a brief development description and we'll provide a fixed-fee quote by return — no obligation.
Flood Risk Assessments
Flood Zone 1 FRA
Simple Flood Zone 1 sites — usually where the site is over 1 hectare or a minor development. Flood-source review, drainage overview and a planning-ready report.
- Sites over 1ha in Flood Zone 1
- Straightforward, desk-based
- Surface water & drainage note
- 5–10 working days
Change of Use FRA
Bread-and-butter change-of-use assessments in Flood Zone 2 — vulnerability re-classification, safe access and floor levels.
- Class MA & conversions
- Vulnerability re-classification
- Finished floor levels & access
- 5–10 working days
Householder Extension FRA
Proportionate FRA for single- and two-storey extensions in a flood zone, written to satisfy the LPA first time.
- Extensions in FZ2 / FZ3
- Flood-resilient design measures
- EA standing-advice compliant
- 5–10 working days
Garden Room / Outbuilding FRA
Concise FRA for garden rooms, offices, annexes and outbuildings that need planning in a flood zone.
- Garden offices & annexes
- Displacement / floodplain check
- Floor-level & resilience advice
- 5–10 working days
Higher-Risk / Tidal FRA
Flood Zone 3 (and tidal) sites for more vulnerable uses — including Sequential and Exception Test support and modelled flood levels.
- Flood Zone 3 / tidal FZ3a
- Sequential & Exception Test
- EA modelled flood levels
- Safe access & escape
Office-to-Residential / London FRA
Higher-complexity conversions and London sites — defended tidal risk, basements and borough-specific requirements.
- Office → residential (Class MA)
- Defended tidal / London boroughs
- Basement & resilience issues
- Borough drainage standards
SuDS Drainage Strategies & Design
Our fixed-fee model means you always know the cost upfront — and that cost covers the full scope until the job is done. We don't charge by the hour, and we don't reduce quality to hit a price point. Fixed scope, fixed cost, delivered on time.
FRA + Drainage Strategy
Our most common package for a new dwelling — full FRA plus a SuDS-led surface water drainage strategy the LLFA will approve.
- New dwellings & small sites
- FRA + SuDS drainage strategy
- Greenfield run-off & attenuation
- LLFA proforma completion
FRA + SuDS + Detailed Design
The full package: FRA, SuDS strategy and detailed drainage design with calculations and drawings, ready for condition discharge.
- Report, calculations & drawings
- Hydraulic design (Causeway Flow+)
- AutoCAD drainage layouts
- Condition-discharge ready
Surface Water Drainage Strategy
Standalone SuDS / surface water drainage strategy for planning — scales with plot size and complexity.
- Outline & full strategies
- SuDS hierarchy (CIRIA C753)
- Greenfield run-off (FEH22)
- LLFA-ready report
Detailed SuDS / Drainage Design
Detailed design for planning-condition discharge — hydraulic calculations, layout drawings and specifications.
- Attenuation & flow-control design
- AutoCAD drawings
- Construction specification
- LLFA SuDS proforma
Other Services
Flood Warning & Evacuation Plan
FWEP add-on alongside an FRA, or standalone — essential for highly vulnerable sites in Flood Zone 3.
- Priced as an add-on or standalone
- Triggers, roles & safe routes
- EA-focused
Flood Consequence Assessment (Wales)
TAN15 Flood Consequence Assessments for planning in Wales — all Welsh LPA areas, using NRW mapping.
- TAN15 / Planning Policy Wales
- NRW flood mapping
- All Welsh LPAs
Sequential & Exception Test
Standalone Sequential Test evidence and Exception Test submissions for Flood Zone 2 and 3 development.
- Standalone or with an FRA
- NPPF-compliant evidence
- Supports the LPA's test
Soakaway Testing (BRE 365)
BRE Digest 365 infiltration testing via our ground-investigation partner — for soakaway and infiltration SuDS design.
- Trial-pit infiltration testing
- Feeds the drainage design
- Self-test pack for remote sites
Flood Risk Report / Screening
A concise, desk-based flood screening for lower-risk sites, due diligence and FZ1 statements. Credited against a full FRA if one is needed.
- 48-hour turnaround
- All flood sources screened
- Credited against a full FRA
S23 Watercourse Consent
Ordinary Watercourse Consent applications to your LLFA for culverting, bridging or diversion works.
- Culvert / bridge / diversion
- LLFA application
- All LLFA formats
All fees shown are indicative starting fees + VAT. Complex sites, major schemes or sites requiring hydraulic modelling are priced individually. We always provide a fixed fee before starting work — contact us with your site address and we'll quote within 24 hours.
What Affects the Cost of a Flood Risk Assessment
Six things decide where a quote lands — and why two "FRAs" can cost very different amounts.
The flood zone
Flood Zone 1 needs a short statement; Zones 2 and 3 need Environment Agency data, design flood levels and mitigation. The higher the risk, the more work the council expects to see.
The type of development
An extension is proportionate and quick. A new dwelling, a change of use to residential or a caravan site brings in vulnerability, safety and often the Sequential and Exception Tests.
The data required
Higher-risk sites need the Environment Agency's detailed data (a Product 4) and sometimes model outputs; we obtain and interpret these as part of the fee.
Whether drainage is included
Many councils want a surface water drainage strategy with the FRA. Combining the two is cheaper than commissioning them separately — hence the combined fee.
Site size and complexity
A single plot is straightforward; a large or multi-parcel site needs more modelling, more drawings and more calculations.
Timescale
Our standard delivery is 5–10 working days. Genuine urgency can usually be accommodated — ask, and we'll tell you honestly what's possible.
Why our fees are lower than you might expect
Three reasons, none of them corners cut. First, no VAT: Flood Risk Environmental is not VAT registered, so the price you're quoted is the price you pay — around 20% less than the same fee from a VAT-registered firm. Second, the work is done personally by one experienced consultant rather than passed through a team, so there's no overhead built into the price. Third, having reviewed applications from inside a Lead Local Flood Authority, we write reports that are accepted first time — which means no paid-for revisions and no second application.
What you don't get is a cheap report that fails validation. Every FRA is written to the current NPPF, Environment Agency standing advice and the council's own requirements, and we support it through to determination.
Frequently Asked Questions
Get a Free Quote
Free, no-obligation fixed-fee quote within 24 hours. All flood zones and LLFAs covered.
Get a Free QuoteOr contact us directly: 07826 705389 •