A Flood Risk Assessment (FRA) evaluates the likelihood of flooding at a particular site and examines its potential impact on people, property and the environment.
At Flood Risk, Environmental and Utilities, we understand that navigating flood risk regulations and securing development approval can be difficult. Our team of experts delivers clear, cost-effective solutions to help developers, land agents, planners and property owners meet statutory requirements and move projects forward with confidence.
Why Flood Risk Assessments are Important
Regulatory Compliance
The National Planning Policy Framework (NPPF) and associated technical guidance set out clear requirements for considering the risk of flooring in planning applications. Local planning authorities demand FRAs for developments in Flood Zones 2 and 3, or where a site is over one hectare in Flood Zone 1.
Protecting Lives and Property
Floods can cause catastrophic damage and with weather becoming more extreme, it’s not a risk you want to take. A FRA identifies any particular hazards on your site: river flooding, surface water run-off, sewer flooding, and recommends measures to mitigate such issues.
Identifying the risks early on reduces the likelihood of costly redesigns or emergency works later on.
Environmental Responsibility
Poorly planned developments can exacerbate the risk of floods downstream and harm local ecosystems. A flood risk assessment helps integrate SuDS (Sustainable Drainage Systems), improving biodiversity and protecting the quality of water.
Make Insurance Easier
Lenders and insurers increasingly demand evidence of flood resilience. An indepth report can make it easier to secure favourable finance and insurance terms.
By pinpointing risks early on, your budget can factor in the cost of protecting against such problems. This might include through the use of attenuation tanks, raised floor levels or flood barriers. No unexpected surprises involved.
When Do You Need a Flood Risk Assessment?
It’s vital for developments in Flood Zones 2 and 3. In Flood Zone 2, it means there is a medium probability (between a 1 in 100 and 1 in 1,000 annual chance of river flooding). But in Flood Zone 3, there’s an even higher probability (greater than a 1 in 100 annual chance).
Any proposal for new dwellings, or those sites used for important buildings (e.g., care homes, schools), or extensions in these zones triggers an FRA.
Major Developments Anywhere in the UK
An assessment is vital for any projects creating 10 or more homes, residential sites larger than 0.5 hectares, or non-residential floorspace over 1,000 m². Even in Flood Zone 1, a site of this scale needs an FRA to assess potential sources of flooding, including surface water and groundwater.
Sites Over One Hectare in Flood Zone 1
Although classified as ‘low probability’, large sites can generate significant surface water run-off.
An FRA ensures adequate drainage and that existing downstream watercourses are not overwhelmed.
Change of Use or Redevelopment
Converting a commercial building to residential use in a zone at risk, or redeveloping brownfield land, often requires reassessment. The FRA must confirm that new occupiers will be safe and that flood risk will not increase elsewhere.
Sensitive Infrastructure and Utilities
Utilities installations (pumping stations, substations, waste water treatment works) must maintain uninterrupted service. Even temporary works (e.g., construction compounds) can require an FRA to prevent pollution incidents during high water events.
What Does a Flood Risk Assessment Include?
A thorough FRA comprises several key stages:
- Site Appraisal and Data Gathering. This involves gathering Environment Agency and local authority flood maps, historic records of any incidents, geology and topography. We will identify all sources of flood risk: fluvial, tidal, surface water, sewer and groundwater.
- Risk Analysis. Our experts quantify the probability of each flood source affecting the site. Model flood depths, velocities and extents under present-day and future climate change scenarios.
- Vulnerability Classification. Classify the proposed development’s vulnerability (e.g., “more vulnerable” residential vs. “less vulnerable” storage). Apply the Sequential Test and, if necessary, the Exception Test to justify development in higher-risk zones.
Afterwards, you can then take the necessary measures to mitigate the risks and prepare your site for use.
Why Choose Flood Risk, Environmental and Utilities?
Our consultants hold Chartered status and always have an up-to-date knowledge of Defra, Environment Agency and CIRIA guidance. We can help you meet compliance requirements, along with gaining knowledge of exactly what a project will cost.
Along with flood risk assessments, we advise on environmental impact assessments, contaminated land, ecology surveys and utility design.
A Flood Risk Assessment is not just a regulatory hoop to jump through: it’s a vital tool for providing safe, sustainable and economically viable places to live or work.
At Flood Risk, Environmental and Utilities, we combine technical rigour with a client-focused approach to deliver FRAs that protect lives, assets and the environment while keeping your project on track.
Whether you’re embarking on a new housing scheme or converting a historic building, contact us today to find out how we can help.