Sussex North Water Certification Scheme (SNWCS)
The Sussex North Water Certification Scheme (SNWCS), formerly the Sussex North Offsetting Water Scheme or SNOWS, is a water certification initiative led by the Sussex North authorities (Horsham DC, Chichester DC, Crawley BC, Mid Sussex DC, South Downs National Park Authority & West Sussex CC) located in Southern Water’s Sussex North Water Resource Zone (WRZ). The scheme will provide applicants with an affordable, accessible way to demonstrate that their development can be constructed in line with Habitats Regulations requirements. It will allow the Sussex North authorities to deliver necessary housing and other development to support local needs while meeting water neutrality requirements.
The primary role of SNWCS is to ensure that increased water demand generated by new developments does not exceed the baseline water savings generated by Southern Water in their next Water Resources Management Plan (WRMP24) and therefore increase pressure for further water abstraction close to the Arun Valley.
Whilst water neutrality requirements are compulsory for developers or applicants seeking approval for new water-consumptive development in Sussex North, the use of SNWCS as a means of meeting these requirements is optional. Developers and applicants have the freedom to choose whether they prefer to utilise SNWCS or implement their own water offsetting solutions that align with water neutrality requirements.
Applicants with eligible developments (see below) will be able to receive SNWCS certification covering the planned water use of their new developments, following taking steps to reduce the water use of their developments in line with relevant planning policies , and subject to the scheme having available capacity.
How to access SNWCS
Our SNWCS Applicant User Guide is published on this web page, which provides further details of how to access SNWCS.
The scheme will rely on developers requesting SNWCS certification at the application stage, at which point the application will be prioritised against the current available capacity in the scheme. If there is sufficient capacity to meet the development’s needs, the applicant will be able to secure their access into SNWCS. If the application is granted and the SNWCS certification charge is paid in full, SNWCS will certify that the application can be constructed in line with Habitats Regulations requirements. If there is insufficient capacity in the scheme to meet the development’s needs, the applicant and DM officer will be notified. The applicant may then need to consider an alternative water neutrality solution to SNWCS or await further capacity becoming available in SNWCS.
We also aim to launch an SNWCS early access service, allowing developers to access SNWCS prior to submitting their application, however this will be after the launch of the main scheme.
The costs for SNWCS certification comprise the scheme operating costs only. SNWCS will not be charging for any part of Southern Water’s Water Resources Management Plan (WRMP24) baseline water savings, because these are already funded by Southern Water.
Related Files
Development eligibility for SNWCS certification
Applicants will be able to request Sussex North Water Certification Scheme (SNWCS) certification for their development’s water offsetting needs, unless it is:
1. Development where the principle is not in accordance with:
b) a made or post-examination neighbourhood plan;
All of the documents/sites referred to in a) and b) have informed the preparation of Southern Water’s Water Resources Management Plan 2024 calculations of water demand.
Non-qualifying development incudes: housing development outside settlement boundaries on unallocated sites; employment development on unallocated sites and /or outside of existing employment sites (unless supported by economic planning policies); or development not otherwise accepted in-principle by way of specific development plan policies. Such policies include:
- retirement and specialist care,
- gypsy and traveller sites,
- tourism,
- and some minerals and waste development
and/or
2. Development permitted by virtue of the Town and Country Planning (General Permitted Development) (England) Order 2015 (or as subsequently amended) (GPDO)*
* Excluding applications submitted to SNWCS for development by a local authority (as defined in Schedule 2, Part 12 of the GDPO)
SNWCS launch date
We aim to launch SNWCS in summer 2025. Further details will be provided in due course.
SNOWS costs
The costs for accessing SNWCS (the ‘SNWCS access charge’) were agreed at the HDC Cabinet Meeting on 21 May 2025.
Once accepted for SNWCS certification, applicants will need to pay a one-off SNWCS certification charge of 80 pence per litre of water (per day) used in a development. To assist with the understanding of how this charge will operate, two worked examples are provided below:
Example 1
An application for a 10-dwelling housing development, with each house built to a water efficiency standard of 85 litres per person per day, with an average occupancy rate of 2.5 people per house.
Total planned water use = 10 units x 85 litres x 2.5 occupancy rate = 2,125 litres per day
SWNCS certification charge = 2,125 litres x £0.80 access charge = £1,700
In this case the applicant would need to make a one-off payment of £1,700 to secure their SNWCS certification for this application following the grant of planning permission. No further payments would be required.
Example 2
An application for a new town centre café with a calculated annual water use of 1.46 million litres.
Total planned water use = 1,460,000 litres / 365 days = 4,000 litres per day
SNWCS certification charge = 4,000 litres x £0.80 access charge = £3,200
In this case the applicant would need to make a one-off payment of £3,200 to secure their SNWCS certification for this application following the grant of planning permission. No further payments would be required.