Flood Risk Consultancy

A focused remote consultancy stage that is often used as the starting point for a project. We review the information you already have, talk through what has happened on site and what you need to achieve, and interpret the flood mapping and other data in context. From that we can identify the real constraint and set out the most appropriate way forward.

The outcome may be an initial advice note, clear recommendations or a defined brief for further work, allowing any surveys, assessments or design input to be properly targeted. This ensures the approach is tailored to the site and avoids committing to the wrong scope too early.

This is a paid professional consultancy stage and does not include mitigation design.

Where a desktop review is not sufficient, a senior consultant can attend site to understand how the land, drainage and surrounding features actually interact. This is a fact-finding stage used to talk through what has happened, what you are trying to achieve and what the real constraints are.

The value is in establishing the correct technical position and collecting the information needed to brief any further work. If additional investigations are required – for example infiltration testing, CCTV Drainage Surveys or a more detailed assessment for the changing landscape of drainage design – they can then be properly specified and scoped.

After the visit we set out clear next steps and, if needed, prepare a tailored scope and fee for the next stage. Consultancy is normally undertaken on a day-rate basis plus travel.

At the highest level of our consultancy offering, we act as Expert Witnesses in flood and drainage disputes. This involves the production of CPR 35 compliant reports, ensuring independence and clarity when providing evidence to the court.

Cases often involve disagreements between parties on matters such as flood risk, property damage, or drainage responsibilities.

Our Flood Risk Director, John Mattinson, leads this service. With extensive experience in both consultancy and litigation support, John specialises in:

• Preparing CPR 35 compliant reports
• Investigating complex flood and drainage issues
• Acting as an independent expert where disputes require clear, evidence-based opinion

This service is typically instructed by solicitors, insurers, or directly by clients involved in legal proceedings.

Read John’s blog on the Role of the Expert Witness in Flood and Civil Engineering Projects

If your project is moving towards a planning application, a Flood Risk Assessment will normally be required. Our consultancy work often forms the first step in defining the scope, programme and level of technical input needed before the full assessment is commissioned. You can find out more about our approach to planning-led Flood Risk Assessments below.

A flood risk consultant is not there to simply describe a flood zone or produce a report. The role is to understand how flood risk interacts with a site, review how changes to levels, layout or drainage will influence that risk, and identify a strategy that allows development to proceed safely and in line with planning policy. That may involve interrogating hydraulic model data, understanding the wider catchment and drainage network, or assessing how the site functions during a flood event rather than how it appears on mapping.

That can include reviewing hydraulic model data, advising on finished floor levels, coordinating the drainage approach for a Surface Water Drainage Strategy, defining safe access and egress and, where necessary, setting out a phased strategy for mitigation and future resilience. In many cases the most valuable input happens before a report is written, when the layout and levels are still flexible.

We have set this out in more detail in our article:

→ The role of a flood risk consultant in planning and design

The value of this stage is in understanding the site in context before fixed solutions are pursued. Many flood and drainage reports are remote and standardised, but when the physical context, constraints and opportunities are reviewed early, the technical approach can be shaped to suit the project rather than the project being forced to suit a report. That early investment often leads to simpler solutions, reduced cost and better long-term performance.

This stage also allows our team to contribute to planning, layout and design decisions while they are still flexible. By working alongside architects, planning consultants and engineers, flood risk and drainage can be considered as part of the overall development strategy rather than as a late constraint.

A proportionate brief for any further work is then based on what is actually required, which reduces abortive cost, avoids unnecessary surveys and ensures that future assessments and designs are properly targeted.

Taking a holistic view of the site also allows wider benefits to be identified. Surface water management can be aligned with levels strategy, access, landscape and SuDS to provide not only compliance, but amenity, biodiversity and long-term asset value.

Where independent opinion is required, this consultancy provides a defensible technical position that can be relied upon for planning, investment or legal purposes.

Our flood risk consultancy work ranges from individual properties through to large-scale strategic studies.

As the advice is bespoke, the scope varies with the client. In some cases that may be homeowners & buyers who need to understand the risk to a single building. In others it is an architect or planning consultant looking for early input so that levels, layout and drainage strategies can be considered.

We also support local authorities, the Environment Agency and DEFRA, where the work forms part of the wider evidence base for managing flood risk. This includes Strategic Flood Risk Assessments to inform planning, Section 19 Flood Investigations following significant flood events, and catchment studies that bring together funding and long-term intervention.

Alongside this we work with community groups on catchment plans, funding applications and Natural Flood Management schemes, reflecting the growing role of nature-based solutions in managing flood risk. You can read more about this approach in our article “Working with Nature: The Rise of Natural Flood Management”.

An example of this approach can be seen in the case study below, where we undertook an initial flood risk review for a community in Leicestershire and developed it into a wider catchment-led strategy.

You can view the case study below.

Flood risk consultancy is often the first step, but it rarely sits in isolation. From that initial advice we regularly progress into Options Development & Design, Surface Water Drainage Strategies, Land Development Engineering or applications to support obtaining Environmental Permits. This allows the flood risk strategy to move from assessment into a coordinated, buildable design.