Sussex North Offsetting Water Scheme (SNOWS)

SNOWS is a water management 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 a water neutral way, allowing the Sussex North authorities to deliver necessary housing and other development to support local plan growth while meeting water neutrality requirements.

The primary role of SNOWS is to ensure that increased water demand generated by new developments does not exceed the water savings generated by Southern Water in their next Water Resources Management Plan (WRMP) (and therefore increase pressure for further water abstraction close to the Arun Valley). Where required, we will develop our own capacity by installing, monitoring, and maintaining water saving measures elsewhere in the WRZ.

Whilst water neutrality requirements are compulsory for developers or applicants seeking approval for new water-consumptive development, the use of SNOWS for offsetting is optional. Developers and applicants have the freedom to choose whether they prefer to utilise SNOWS or implement their own water offsetting solutions that align with water neutrality requirements.

Applicants with approved developments (see below) will be able to purchase access into SNOWS to cover any remaining water use of their new developments after they have taken steps to reduce the water use of their developments in line with the Sussex North authorities’ local plan water neutrality policies, and subject to the scheme having available capacity.

How to access SNOWS

Our SNOWS Applicant User Guide is published on this web page, which provides further details of how to access SNOWS.

The scheme will rely on developers requesting  access to SNOWS 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 SNOWS. If the application is granted and the SNOWS access charge is paid in full, SNOWS will confirm that the application has been assigned to available water capacity. 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 offsetting solution to SNOWS or await further capacity becoming available in the SNOWS scheme.

We also aim to launch a SNOWS pre-application advice scheme, allowing developers to access SNOWS prior to submitting their application, however this will be after the launch of the main scheme.

SNOWS will initially determine whether Southern Water’s WRMP ‘baseline’ water savings are sufficient to demonstrate water neutrality. Where we forecast that Southern Water WRMP baseline savings will be insufficient to meet local plan growth water demand forecasts, SNOWS will supplement the Southern Water savings with a separate offsetting programme.

The costs for SNOWS access comprise the scheme operating costs and any SNOWS offsetting activities only. SNOWS will not be charging for any part of Southern Water’s Water Resources Management Plan (WRMP) baseline savings, because these are already funded by Southern Water.

Related Files

Which developments can access SNOWS

Applicants will be able to access SNOWS for their development’s water offsetting needs, unless it is:

  1. Development where the principle is not in accordance with an adopted development plan or neighbourhood plan, or a post-submission local plan (all of which have informed the preparation of Southern Water’s Water Resources Management Plan 2024 calculations of water demand).  This includes housing development on unallocated sites outside settlement boundaries, 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 SNOWS for development by a local authority (as defined in Schedule 2, Part 12 of the GDPO)

When will SNOWS launch?

We aim to launch SNOWS in Spring 2025. However, we anticipate low credit availability through 2025 until Southern Water’s Water Resources Management Plan (WRMP) is adopted.

SNOWS costs

A report to agree SNOWS costs is being considered at the Cabinet Meeting of 28 May 2025. https://horsham.moderngov.co.uk/documents/g2578/Public%20reports%20pack%2021st-May-2025%2017.30%20Cabinet.pdf?T=10

This report proposes a one-off charge of 80 pence per litre of water 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 water offsetting requirement = 10 units x 85 litres x 2.5 occupancy rate = 2,125 litres per day

SNOWS access 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 SNOWS access for this application following the grant of planning permission.

Example 2

An application for a new town centre café with a calculated annual water use of 1.46 million litres.

Total water offsetting requirement = 1,460,000 litres / 365 days = 4,000 litres per day

SNOWS access 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 SNOWS access for this application following the grant of planning permission. No further payments would be required