Flood and Water Management / Drainage

Surface Water Drainage and SuDS

Milton Keynes Council is a Lead Local Flood Authority (LLFA) and as such is a statutory consultee to the planning process for surface water on all major developments. The consultation requirement and description of major development is detailed within the Town and Country Planning (Development Management Procedure Order). This applies to all new major planning applications. However it should be noted that Milton Keynes Council may also comment on non-major applications.

In assessing an application, the LLFA and Local Planning Authority will need to be satisfied that:

  • Any proposals meet national and local policies;
  • The proposed minimum standards of operation are appropriate;
  • A minimum standard is set out to which the sustainable drainage systems must be maintained;
  • Through the use of planning conditions or planning obligations there are clear arrangements in place for ongoing maintenance over the lifetime of the development, including clearly identifying who will be responsible for maintaining the sustainable drainage systems and that funding for maintenance is fair for householders and premises occupiers

Flood Risk and Surface Water Policy Requirements

Plan:MK (the Local Plan for Milton Keynes) was adopted on 20th March 2019. As outlined in the plan, the early masterplan for Milton Keynes sought to reduce flood risk via the development of an innovative approach to flood risk based on a strategic water management system and planned green infrastructure provision.

However as outlined in the Level 1 Strategic Flood Risk Assessment (2015), there are a number of areas across the Borough at risk of flooding from various sources and it is expected that, even with no further development, the impacts of climate change are likely to increase this risk. It is therefore necessary that a robust and sustainable approach is taken to reducing and mitigating the potential impacts that climate change may have upon the area.

Policies FR1 – FR3 of Plan:MK includes locally specific strategic flood risk management policies to maintain and continue the exemplar sustainable drainage model of Milton Keynes which prohibits development within the floodplain and seeks flood management and drainage infrastructure to be provided as strategically as possible and as part of a maintained, multi-functional blue-green infrastructure.


Guidance for Developers

Milton Keynes Council has published specific guidance on the preparation of surface water drainage strategies (see below). This provides information on the level of detail we require depending on the type of planning application. The document should be used by all developers and their consultants who wish to submit an application in Milton Keynes.

Reviews of surface water strategies or flood risk assessments should be requested via our formal pre-application advice service, where a planning officer will provide their opinion and guidance on the likely outcome of your application.

Sustainable Drainage Systems (SuDS)

Sustainable Drainage Systems (SuDS) mimic natural drainage to manage surface water run-off from a development. SuDS allow for the collection, storage and treatment of surface water in order to reduce flood risk caused by development. SuDS generally replace traditional underground, piped drainage systems. The aim of SuDS is to keep water on the surface as much as possible. They can be integrated into both rural and urban developments.

Benefits of SuDS

  • Provides the potential to re-connect societies with water, providing benefits for amenity, health and well-being.
  • SuDS can provide new natural habitats, connecting nature and wildlife with urban environments
  • Keeping water on the surface allows any problems to be identified and managed quickly. Management of SuDS features can generally be cheaper, less time consuming and more straight-forwards than conventional drainage systems

Last Updated: 16 November 2021