The SuDS Assessment Spreadsheet is only one part of the information required to demonstrate compliance with the Ebbsfleet SuDS guidance. Planning submissions should clearly show how Sustainable Drainage Systems have been incorporated into the design and how the selected measures work together as a connected SuDS train.

Applicants should submit sufficient information to demonstrate how Sustainable Drainage Systems (SuDS) have been integrated into the design of the development and to enable EDC to assess compliance with the SuDS Selector and Sustainability Assessment System.

When should the assessment be completed?

The SuDS Assessment Spreadsheet should be completed for relevant planning applications, including Outline and Reserved Matters Applications.

The level of information provided should be proportionate to the stage of the planning process:

• Outline Applications should demonstrate the intended SuDS strategy, the types of SuDS measures proposed and how surface water management has been considered within the development concept.

• Reserved Matters Applications should identify the proposed SuDS features, the locations in which they are intended to be provided and the housing, apartment or street typologies to which they relate.

The assessment is intended to demonstrate the proposed SuDS approach and assist EDC in assessing site-level SuDS provision. Detailed technical specifications, drainage calculations and construction information may be secured through planning conditions and confirmed at a later stage where appropriate.

What must be submitted?

Completed SuDS Assessment Spreadsheet

A completed SuDS Assessment Spreadsheet must be submitted for all relevant applications.

The spreadsheet should:

• Include all housing, apartment and street typologies proposed within the development.

• Identify the selected building-scale, plot-scale and street-scale SuDS features.

• Show the score and compliance status for each typology.

• Identify any typologies that do not meet the minimum score.

Where the minimum overall score is not achieved

The completed spreadsheet may identify housing, apartment or street typologies that do not achieve the minimum overall score. Where this occurs, the applicant should provide a short justification explaining:

• why the minimum score cannot reasonably be achieved;

• any site, design or delivery constraints affecting the available SuDS measures;

• the alternative measures considered; and

• how the application otherwise contributes to site-level surface water management.

EDC will consider the justification alongside the proposed SuDS strategy and the wider design and sustainability performance of the application.

Supporting Information

SuDS Drawings and Plans

Applicants should submit drawings that identify all SuDS features included within the assessment spreadsheet.

The drawings should show:

• The location of each SuDS feature.

• The scale at which it operates (building, plot or street).

• How features connect together as part of the wider SuDS train.

The features shown on the drawings should correspond with those entered in the SuDS Assessment Spreadsheet.

The level of detail should be proportionate to the application stage. Detailed engineering design is not required unless otherwise requested through the planning process.

Drainage Information

Applicants should briefly explain how the selected features form part of the site’s overall drainage strategy and contribute to a SuDS-first approach. This may be provided through the drainage strategy, Design and Access Statement or other supporting documentation.

Detailed hydraulic calculations and technical drainage design will be considered separately through the drainage process and the requirements of the Lead Local Flood Authority (LLFA).

Soil and Construction Information

Where the assessment includes rain gardens, filter strips, SuDS-enabled tree pits or other measures that rely on soil performance, applicants should identify the intended soil approach and relevant protection measures.

This may include:

• Confirmation that appropriate SuDS soils will be used.

• Information on how soils will be protected from compaction during construction.

• Identification of below-ground landscape elements such as soil cells where relevant.

Detailed construction specifications are not required at this stage unless specifically requested.

Management and Maintenance

Applicants should explain how SuDS features will be maintained for the lifetime of the development.

The submission should identify:

• Who will be responsible for maintaining the features.

• Whether features are intended for private, communal or adopted management.

• Any key maintenance considerations associated with the proposed SuDS measures.

Detailed maintenance manuals are not normally required at planning application stage.

Relationship with LLFA Requirements

The SuDS Assessment Spreadsheet supports EDC’s assessment of site-level SuDS and the relevant criteria within the Sustainability Assessment System.

The spreadsheet and supporting information required by this guidance do not replace the drainage information required by the Lead Local Flood Authority. Applicants must continue to comply with relevant planning policy, drainage requirements and supporting information required by the LLFA.

The SuDS Selector focuses on the selection and integration of SuDS measures within buildings, plots and streets. Technical drainage matters, including hydraulic performance, runoff rates, attenuation requirements, drainage calculations, detailed design, verification and other drainage evidence, will continue to be considered through the drainage process and the requirements of the LLFA.

Applicants are encouraged to engage with the LLFA at an early stage to agree the drainage approach, supporting information and technical requirements for their proposal.

What Happens Next?

EDC will review the completed assessment, supporting drawings and any accompanying justification statements as part of the planning process and Sustainability Assessment System review. The information will be used to help assess how effectively SuDS have been integrated into the design of the development.