Surface Water Management

At the planning stage, for sites that exceed 1 ha in area or, are identified as being a site with problematic drainage or localised flooding issues, planning policy requires that a Surface Water Management Strategy is developed to demonstrate that the proposed development will not exacerbate flood risk, either on site or elsewhere.

This strategy can be developed as either a stand-alone study, or be included as part of a Flood Risk Assessment and in most cases it is based on a desk-top study that tests the application of the preferred hierarchical approach to surface water discharge, i.e. via infiltration, connection to a watercourse or to a public sewer.


Sustainable Drainage (SuDS)

Surface water drainage methods that take account of quantity, quality and amenity issues are collectively referred to as Sustainable Drainage Systems (SuDS). These systems are more sustainable than conventional drainage methods because they help to manage runoff rates, reducing the impact of urbanisation on flooding and protect and enhance water quality.

These systems do this by dealing with runoff close to where the rain falls, managing potential pollution at its source and protecting water resources from point pollution.


Numerical Analysis

Herrington Consulting has range of numerical models that assist in the development of Surface Water Management Strategies. These include FEH, ReFEH and Micro Drainage Source Control. For complex sites direct rainfall 2D overland flow path and flood route modelling can also be undertaken using Surface-water Modelling System & TuFLOW. Further information on our numerical modelling capabilities can be found on our Numerical Modelling page.