Flooding and Drainage

The pressures of a growing economy and population has always placed development in potential conflict with other functions of the landscape, including its ability to accommodate flood waters at times of high rainfall.  Here at Yellow Sub Hydro, we can call upon the expertise needed to help deliver sustainable development and drainage strategies, that work in concert with natural processes. 

The delivery of sustainable development with respect to flooding is typically twofold: 

Firstly, identifying suitable development for the magnitude and frequency of flooding which that particular site may suffer. 

Secondly, designing a drainage strategy that ensures the development does not worsen flooding elsewhere, and if possible ameliorates it.  


Understanding and assessing flood risk

At its simplest, flooding is just water where we don't want it to be. In our homes, our shops, our schools and businesses, or interacting with our transport or service infrastructure.   

Flooding is rarely just a natural phenomenon, but a result of a complex interplay between natural systems, the built form of development, land management and human-induced climate change.  The cause of flooding is not constrained to rivers bursting their banks.  There are various mechansims by which flooding can occur, and undertstanding them is important to assessing risk and providing suitable mitigation measures.    

Responsible development in the modern world requires understanding and proacitve management of the issue of flooding.

We seek to apply a holistic and intelligent approach to development projects.  How, for example, do flood protection measures interplay with foundation design or contaminated land clean-up?  Can the management of soils on development sites benefit both the flood-protection and land quality requirements?

If you have a flooding related issue for your development, please give us a call.

Flooding can come from a number of complex and inter-related sources. 

  • Fluvial 
  • Pluvial
  • Groundwater
  • Tidal
  • Storm surge

No matter what the source or the mechanism, the end result is damage, disruption and (at the extreme) loss of life. 


Sustainable Urban Drainage Systems (SUDS)

SUDS are used in all types of development to provide a natural approach to managing drainage, slowing the flow of water into rivers and streams.  This in turn helps to reduce the magnitude, frequency and impacts of flooding.

SUDS can also prevent water pollution, and can create green spaces and habitat for wildlife in towns and cities.

SUDS are a legal requirement for all new developments, except for surface water drainage from single dwellings and developments that drain to coastal waters.

We provide strategic advice and outline drainage design principles, targeted at achieving planning permission for development.  We also have experience in the temporary drainage of construction sites, and minimising the impact of construction-site run-off on the environment.

SUDS are an essential part of any modern development and identifying practical and economic solutions is a key factor in project feasibility.

How we can help:

We can provide a range of hydrological consultancy services, tailored to your project.  Where possible, we seek to add value by combining these services with our brownfield consultancy work, thus maximising the potential for project benefits that this holistic approach brings.  Our typical outputs with respect to flooding and drainage are:

·  Flood risk assessment reports

·  Sequential testing

·  Exception testing

·  Outline drainage strategies

·  Flood modelling

·  Flood warning and evacuation plans

·  Strategic Advice

·  Expert witness


Let's connect

We're always keen to help

drop us a line and we'll be in touch soon.

UK: (+44) 02920 099 310