Surface Water Drainage Strategies (SuDS)

We offer preliminary and detailed Surface Water Drainage (SuDs) design services to support planning applications

Development within flood risk zones now invariably require some form of Surface Water Drainage strategy. We can develop a Surface Water Drainage strategy for your development as a separate piece of work or in conjunction with your Flood Risk Assessment.

What is a Surface Water Drainage Strategy

A Surface Water Drainage Strategy (also known as SuDS in urban areas) provides a natural approach to managing surface water run-off from a site by reducing the rate of run off through the promotion of infiltration or by storage. The benefits include:

• reducing the risk of flooding
• preventing water pollution
• increasing green amenity space and providing habitat for wildlife in urban areas

What we can do:

We are able to design of Surface Water Drainage strategies for developments using one or a combination of the following techniques:

• soakaways
• green roofs
• permeable surfaces
• infiltration trenches filter drains and filter strips
• swales – shallow drainage channels
• detention basins, purpose built ponds and wetlands

Infiltration/Percolation Testing

The installation of a soakaway is the SuDS option preferred by most Local Authorities as it is considered to be the most sustainable. We may therefore need to undertake an investigation in order to confirm  soil types, infiltration rates and groundwater levels  in order to determine whether or not soakaways (or  other infiltration methods) are suitable for the site.

Drainage Modelling

We can also undertake drainage modelling to provide recommendations for sizing and positioning of the soakaways (or other proposed SuDS components) to ensure that they will be able to manage rainfall from the range of normal and extreme storm events as required by the Local Planning Authority.

Should soakaways prove not to be feasible, then a drainage network system will need to be designed to allow for the discharge of surface water to the public foul or surface water sewer. In this case the modelling will need to be undertaken to the satisfaction of both the Local Planning Authority and Sewerage Undertaker.

The Benefits of our Surface Water Drainage Strategies include:

• Improved chances of obtaining planning permission
• Improved communication with regulatory authorities
• You as a client will obtain a better understanding of issues involved
• Reduced risk of hold ups in the planning application process