The SuDS Assessment Spreadsheet should be completed for relevant Outline, Full and Reserved Matters applications and used alongside the SuDS Selector guidance. The level of information included should be proportionate to the application stage. It provides a consistent method for demonstrating how Sustainable Drainage Systems (SuDS) have been incorporated into the development and helps applicants understand whether the proposed measures meet the minimum expectations for Ebbsfleet Garden City.

The spreadsheet evaluates the SuDS features proposed for each housing typology, apartment typology and street type. Each SuDS measure is assigned a score based on its ability to manage surface water and deliver wider environmental benefits. Higher scores are awarded to measures that provide multiple benefits, such as flood risk reduction, biodiversity enhancement and improved placemaking.

How to complete the assessment

Applicants should:

1. Identify the SuDS measures proposed using the SuDS Selector.

2. Enter each housing typology and apartment typology separately.

3. Record the building-scale, plot-scale and street-scale SuDS measures proposed.

4. Enter each street type separately.

5. Review the automatically calculated scores and compliance status.

Where the same building design includes different SuDS arrangements, each variation should be entered as a separate typology

How the scoring system works

The assessment assigns a score to each SuDS feature.

The purpose of the scoring system is not simply to maximise points, but to encourage the selection of a range of connected SuDS features across buildings, plots and streets that work together as a SuDS train.

Each SuDS feature must meet the minimum requirements set out in the spreadsheet before it can contribute to the assessment score. These requirements operate as a pass/fail test for the individual feature. For example, a feature that only partly meets its minimum requirement would not receive a proportionate or partial score.

The overall score is then calculated from the combination of qualifying SuDS features selected for each housing, apartment or street typology.

Minimum typology scores

Houses and Apartments

Each housing or apartment typology must:

• Select at least one building-scale SuDS feature.

• Select at least one plot-scale SuDS feature.

• Achieve a minimum score of 20 points.

Streets

For each street type, applicants must:

• Select at least two street-scale SuDS features.

• Achieve a minimum score of 19 points.

In addition, street and neighbourhood proposals must comply with the minimum technical requirements set out in the assessment spreadsheet.

Applications within larger or phased developments

On larger developments, planning applications may come forward for individual parcels, phases or plots at different times. The SuDS Assessment should be completed for the application being considered and should assess the building, plot and street-scale SuDS measures delivered within that application.

Strategic drainage infrastructure, public open spaces, swales, basins and other neighbourhood-scale SuDS features may be delivered through separate applications or phases. These features remain important parts of the wider drainage strategy but do not replace the need for each development parcel to contribute to surface water management close to where rain falls.

The purpose of the SuDS Selector is to assess site-level source-control measures integrated into buildings, plots and streets, rather than strategic drainage infrastructure that may be delivered elsewhere within the wider development.

The assessment should reflect the level of design information available at the application stage. At Outline stage the assessment may be based on the proposed SuDS strategy and indicative layouts, while later applications may provide greater detail regarding the location and distribution of individual features.

Demonstrating compliance

The spreadsheet automatically calculates scores and identifies whether each housing typology, apartment typology and street type meets the required threshold. This information should be submitted alongside the supporting drawings and drainage information required as part of the planning application.

What happens next?

Once the SuDS Assessment Spreadsheet has been completed, applicants should move to Step 3: Submission Requirements, which explains the drawings, supporting information and evidence that must accompany the planning application.