Flood Risk and Environmental Consultancy for Asset Owners and Commercial Property

Before you can manage flood risk on a commercial property, you need to know what you’re dealing with. A Flood Risk Assessment tells you what the Environment Agency data shows, but it doesn’t explain why a car park floods every winter, where the water is actually coming from, or what the drainage was designed to cope with.

We carry out flood investigations as a starting point for many commercial instructions. That might mean a site walkover and drainage review, CCTV surveys of existing drainage, or hydraulic modelling if there are unresolved questions about a nearby watercourse or culvert. The output is a clear picture of what needs managing and how, not just a report.

For portfolios, we have completed climate change stress testing across a central London portfolio, mapping current and projected flood exposure across a range of climate scenarios. That kind of work gives asset managers something they can act on, whether that’s prioritising capital spend, informing insurance arrangements, or supporting due diligence. We have also carried out a civil engineering and flood review for a commercial site in Leicestershire, where a thorough understanding of the site’s drainage and flood history was needed before the right mitigation approach could be identified.

Not all commercial Flood Risk Assessments are straightforward. The NPPF requires them for most development proposals in flood risk areas, but scope and complexity vary considerably depending on what’s being proposed.

Change of use is where this catches a lot of people out. Moving a building from commercial to residential, or from a lower to a higher vulnerability class under the NPPF’s flood risk classification, requires demonstrating that the new use is appropriate for the flood zone and that safe access and egress can be maintained throughout the development’s lifetime. We handle change of use FRAs regularly, including cases where the Sequential Test and Exception Test need to be addressed. The Lewes New School development is a good example: a former school site repurposed through the planning system, where the FRA had to demonstrate flood risk was appropriately managed for the proposed use.

For straightforward commercial development proposals, we have a strong record of getting FRAs through first time. Our Flood Risk Assessment for a commercial development resulted in planning approval without objection from the Environment Agency, which is often the clearest sign that the scope and technical content were right.

BREEAM is another area where flood risk expertise matters. Credits under the Land Use and Ecology and Water categories can depend on demonstrating flood resilience and sustainable drainage. We work with architects and developers seeking BREEAM credits, providing the technical input needed to support the certification process.

Insurance reviews are increasingly common. When an insurer wants an independent assessment of flood risk at a manufacturing facility, warehouse, or retail site, particularly after a loss or as a condition of renewal, we provide reports that are technically robust and written for a specialist audience. We have completed this type of work for a Devon manufacturing site where the insurance position depended on a credible, independent flood risk opinion.

If you own or manage a commercial site that has flooded, or that you suspect is at higher risk than any map suggests, a Flood Investigation and Management Strategy is usually the right starting point.

This goes further than a standard FRA. It identifies where flooding is coming from (river, surface water, drainage failure, groundwater, or a combination), examines what has been tried before and why it may not have worked, and sets out a prioritised programme of mitigation with costs. It is designed to give you something actionable.

We have used this approach on industrial estates, retail parks, and individual commercial buildings where the flooding history is complicated and the solution is not obvious. In most cases, the investigation reveals things that the initial data did not show.

Commercial operations can introduce environmental risks that sit alongside flood risk but need managing separately.

Environmental permits. Certain commercial activities, including industrial processes, waste operations, and abstractions, require permits from the Environment Agency. If a permit is needed, or if you are expanding operations in a way that affects an existing permit, there are specific requirements to navigate. We provide environmental permits consultancy covering applications, variations, and compliance advice.

Fire water runoff. Commercial and industrial sites storing hazardous materials need to demonstrate they can contain contaminated water released during a fire. It is not enough to suppress the fire if the runoff enters a watercourse. Our fire water risk assessments establish whether containment is adequate and, where it is not, what needs to change. This is increasingly relevant to insurers and to the EA’s permitting requirements.

Drainage problems on commercial property tend to fall into a few categories: systems that were never properly designed, systems modified over time without documentation, and sites where development has changed what the drainage needs to handle.

We carry out drainage reviews and assessments, detailed drainage design, and surface water drainage strategies for commercial clients. This includes SuDS design where the planning system requires it, soakaway design and testing, and CCTV drainage surveys to establish what is actually in the ground before any design work begins.

If drainage has caused issues with neighbouring properties or the local highway, we can also advise on backflow protection and the measures available to reduce the risk of recurrence.