Surface water drainage assessment
|Policy driver||National Planning Policy Framework| Section 10|
Replacement Unitary Development Plan – Policies EP16 and EP17 (This area is currently under review at the national level and is likely to change in the near future - the requirements of this List will reflect these changes as and when they are brought into force.)
|Type of application||Operational development of 100sq metres or over that creates a need for the disposal of surface water, e.g. where a new roof is being created or the ground is being covered by a non permeable surface.|
|Geographic locations where this information is required||Any area of Calderdale|
|What information is required||Confirmation that a feasible, and where necessary, consented, surface water drainage scheme which satisfies national & local guidance has been demonstrated. This report should form part of the Flood Risk Assessment where one is required. Where a Flood Risk Assessment is not required, questions 11-20 of the Surface Water Drainage Self Assessment Form [PDF file 109KB]| should be completed.|
|Where to look for further assistance||See 'Further Information'. If, after reading the Further Information, you are still unsure about the information you submit, contact the Councils Drainage Engineer on 01422 392168.|
- The Technical Guidance to the National Planning Policy Framework | states that developers should seek opportunities for sustainable drainage systems within application sites to reduce flood risk. These should be incorporated within the layout and form of the development. Sustainable drainage systems should be considered in preference to connections to watercourses or sewers.
- Information on sustainable drainage systems for managing surface water are set out in Chapter 7 (‘Managing Surface Water’) of the extant Planning Policy Statement 25: Practice Guide|.
- All new buildings need separate connections to foul and storm / surface water sewers. If an application proposes to connect a development to the existing drainage system then details of the existing system should be shown on the application drawing(s). It should be noted that in most circumstances surface water is not permitted to be connected to the public foul sewers.
- An application should indicate how the development connects to existing utility infrastructure systems. The main planning issue arising is whether the provision of services on site would give rise to any environmental impacts, for example, excavations in the vicinity of trees, archaeological remains, pollution prevention and flood risk.
- Where it is proposed to hard-surface an existing domestic garden information will be required about the proposed surfacing materials and the drainage methods. For further information see the Environment Agency’s publication: Guidance on the permeable surfacing of front gardens|.