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Urban drainage, flood risk and hydraulic modelling specialists
Helping organisations understand, manage and reduce flood risk through advanced hydraulic modelling, expert technical advice and practical drainage solutions.
Specialist hydraulic modelling and urban drainage consultancy
For more than three decades, Richard Allitt Associates (RAA) has supported water companies, local authorities, planning consultants, developers and legal professionals with specialist consultancy services across the UK. Combining industry-leading modelling technology with real-world engineering expertise, we deliver clear insights that help clients make informed decisions with confidence.
Technical expertise, practical solutions
RAA is a specialist flood risk, hydraulic modelling and urban drainage consultancy dedicated to solving complex water management challenges. Since 1996, we have built a reputation for delivering robust technical analysis, innovative thinking and responsive client service.
Our team works across a wide range of sectors, helping clients understand flood risk, plan resilient infrastructure and develop effective drainage strategies. Whether supporting strategic catchment studies, planning applications, infrastructure investment or legal proceedings, we provide trusted advice backed by proven expertise.
Flood risk management
Flood risk management
Our specialist flood risk consultancy services support planning applications, infrastructure projects and flood investigations.
Hydraulic modelling
Hydraulic modelling
We develop robust models with valuable insights into how your drainage systems operate to enhance performance.
Urban flood forecasting
Urban flood forecasting
We help to mitigate urban flooding with expert flood forecasting, simulation techniques and predictive modelling technologies.
Hydrology
Hydrology
We provide specialist hydrology services to quantify rainfall, runoff and catchment response, helping you to understand the risk, optimise designs and meet regulatory requirements.
Sustainable drainage systems
Sustainable drainage systems
Our sustainable drainage systems (SuDS) strategies help to reduce flood risk, improve water quality and enhance urban environments, ensuring systems remain effective and resilient over time.
Expert witness services
Expert witness services
Our experienced professionals provide independent technical expertise for flooding and drainage disputes is reinforced by experienced professionals.
Aerial surveys and data capture
Aerial surveys and data capture
Our advanced drone technology, with specialist engineering expertise, captures high-quality data quickly, safely and efficiently.
We’re a susdrain partner
We are proud to be a susdrain partner helping to promote sustainable drainage schemes (SuDS) and the support of implementation through computer modelling of sewer networks, watercourses and urban flooding.
Find out more about sustainable drainage
Create safer, more resilient communities by helping clients understand, manage and reduce flood risk through innovative analysis and expert advice.
Become the UK’s most trusted specialist consultancy for hydraulic modelling and urban drainage solutions.
We take the time to assess the challenge, identify the most effective methodology and develop a tailored solution that delivers clear, actionable outcomes.
By combining technical excellence with collaborative working, we help clients navigate increasingly complex environmental and regulatory requirements. Using advanced modelling tools, robust data analysis and industry best practice, we provide insights that support better decision-making and long-term resilience.
