Update on Water Neutrality and Water Efficiency in Sussex North Water Supply Zone (SNWSZ)

In October 2025, water neutrality restrictions were officially lifted in the Sussex North Water Supply Zone. On 8 October 2025, Defra announced that an agreement had been reached to unlock new home development in this region, formally ending a four-year development pause caused by water neutrality restrictions due to concerns about water extraction from rivers and wetlands in the Arun Valley.

A further announcement on 31 October 2025 confirmed that Natural England would withdraw their position statement, ending the requirement for Water Neutrality Statements in planning. This decision triggered the policy changes now occurring across the region.

The change is based on new evidence from Southern Water’s Hardham Basin Environmental Study. Natural England confirmed that a new package of ecological measures and amendments to Southern Water’s abstraction licence (to be implemented by March 2026) will “decouple” new development from any potential impact on the Arun Valley. Natural England concluded that new development will not have a “likely significant effect” on the protected sites.

Development Impact Across North Sussex

With the Natural England position statement withdrawn, local authorities no longer require water neutrality statements. The focus has shifted from achieving “neutrality” to proving stringent water efficiency.

Horsham: The council removed Water Neutrality Statement requirements but now requests compliance with the 110 litres per person per day (lpd) standard. All new housing applications must comply with Building Regulations Part G Optional Technical Standard (currently 110 l/p/d) as required by Policy 37 of the Horsham District Planning Framework.

Chichester: Water neutrality requirements have been removed, and the 110 lpd water efficiency standard is now the key requirement. Per Policy NE18 of the Chichester Local Plan 2021-2039, the water efficiency standard for residential development will revert to 110 litres/person/day, or the minimum standards for BREEAM ‘Excellent’ within the Water category for non-domestic buildings.

Crawley: The council confirmed that with the deletion of water neutrality, planning will revert to the 110 lpd standard. As per Strategic Policy SDC4 of the Crawley Borough Local Plan 2023-2040, the water efficiency standard for development will revert to 110 litres/person/day for residential or the minimum standards for BREEAM ‘Excellent’ within the Water category for non-domestic buildings.

South Downs National Park (SDNP): The SDNP has withdrawn its water neutrality requirement. However, Policy SD48 remains in effect, requiring projects that increase a footprint by 100 square meters or more to address water efficiency properly. Water remains a key consideration for projects within the park even without the overarching Water Neutrality Statement.

For Existing Permissions with Water Neutrality Conditions

If an existing permission includes conditions or section 106 obligations for water neutrality, councils will consider applications under section 73 of the Town and Country Planning Act to remove those conditions and replace them with the new, simpler condition requiring compliance with the 110 lpd standard.

For current undetermined applications, developers should contact their case officer immediately to discuss how to proceed. If an application has already been heard by a Planning Committee, it will need to return to the committee to amend the requirements. Councils have advised it may be faster to conclude the application in its current form with the old conditions and then immediately apply to vary the conditions via a section 73 application.

Future Changes

The move to 110 lpd is a clear target but not the end of the story. Discussions are ongoing regarding tighter national standards. There is currently a national consultation on amending Building Regulations to 100 lpd for residential use in water-stressed areas, suggesting the current 110 lpd standard may soon be tightened.

The National SuDS (Sustainable Drainage Systems) guidance recognizes that rainwater harvesting should be promoted. The guidance states that rainwater harvesting “shall be considered” where a development is in an area “identified as seriously water stressed.” Examples for rainwater harvesting consideration include industrial, commercial, horticultural, educational, public sector, residential, and multiple-occupancy buildings where there is demand for non-potable water, available contributing catchment area, or need for landscape irrigation.

How Aegaea Can Help

Aegaea achieved a 100% success rate on Water Neutrality projects by finding innovative ways to meet policy requirements. While this announcement closes Water Neutrality Statement work, Water Efficiency Statements are still required. Aegaea offers assessments and reports needed to ensure planning applications are compliant and successful, particularly regarding water efficiency and surface water drainage requirements.